electroneurography in guillain-barre, syndrome (gbs): sensitivity and specificity

Journal of the Peripheral Nervous System 5:32–51 (2000)

© 2000 Peripheral Nerve Society, Inc.

32

Blackwell Science Publishers

Abstracts of the 5th Meeting of the ItalianPeripheral Nerve Study Group

Salerno, 7–8 April, 2000

Organizing Committee:

Lucio Santoro, M.D.Giuseppe Caruso, M.D.

Department of Neurological SciencesUniversity of Naples “Federico II”

Napoli, Italy

DYSAUTONOMIA IN CRYOGLOBULINEMIC AND ALCOHOLIC NEUROPATHIES

Ammendola A., Ambrosone L.

1

, Ciccone G., Argenzio F.

2

,Cantore R., Iannaccone S., Ugolini G., Di Iorio G.

3

,Migliaresi S.

1

, Bravaccio F.

Second University of Naples – Fac-

ulty of Medicine Chairs of Neurophysiopathology,

1

Rheumatology,

2

Clinical Toxicology,

3

Neurology

Sympathetic Skin Response (SSR) can evaluate theactivity of both sensory afferent and sudomotor sympatheticefferent fibres in peripheral neuropathy (PN). This electro-physiological test was performed in two groups of patients:one with HCV-related mixed cryoglobulinemia (MC) and theother with chronic alcoholism (CA). Thirty consecutive HCV-related MC patients, 25 female and 5 male, aged 35–74 yearsand thirty-three consecutive CA patients, 8 female and 25male, aged 24–69 years were studied. In all cases, neurolog-ical exam, peroneal, sural and ulnar nerve conduction veloc-ity, standardised test battery for autonomic disorder (definedaccording to Bellavere, 1990) and SSR (recorded with elec-trodes attached to the palm and sole and considered abnor-mal if no response was recorded) were performed.

PN was found in 27 MC patients (90%) and in 23 CApatients (69.6%). Autonomic dysfunction, shown by cardio-vascular tests, was found in 3 MC patients, all with PN andin 6 CA subjects, all but one with PN. SSR resulted absent in12 MC patients (40%): three of them with and 9 withoutdysautonomia; SSR was also absent in 9 CA patients(27.2%) (1 with and 8 without dysautonomia).

In MC and CA patients, autonomic dysfunction fre-quency increases when SSR is studied together with stan-dard cardiovascular tests. SSR provides further informationabout sympathetic autonomic system activity and thereforeit is advisable to add this investigation to tests usually uti-lized in functional evaluation of autonomic nervous system.

CAUSE AND CLINICAL–NEUROPHYSIOLOGICAL PICTURE OF PERONEAL NEUROPATHY

Aprile I. MD, Padua L. MD, Meloni A. MD, D’Amico P. MD andTonali P. MD

Institute of Neurology, Catholic University–Rome.

We retrospectively analysed 40 patients with peronealneuropathy (PN) referred to our EMG laboratory during thelast 4 years. Aim of the study was to evaluate the incidenceand causes of PN. Moreover, the relationship betweencauses and clinical-neurophysiological picture was assessedand a follow-up was performed.

Preliminary results showed that, in most cases, associ-ation between PN and surgical event was present (27,5%):unexpectedly, the higher occurrence of PN was observed inpatients who underwent operation in the hip region (pros-thesis). In 20% of cases, a damaging event was not identi-fied. Erroneous postures (kneeling and crossing leg) causedPN in 12% of cases. Prolonged allurement was related in10% of PN (50% of these in intensive care unit admission ).

PN was not significantly related to gender. The age rangeof the patients was extremely wide: from 7 to 80 years(mean 50 years). In more than 50% of cases, neuroapraxicblock was demonstrated to neurophysiological evaluation.

A FAMILY WITH AUTOSOMAL DOMINANT MUTILATING NEUROPATHY NOT LINKED TO EITHER 3q13-q22 OR 9q22 LOCI

Bellone E., Di Maria E., Cassandrini D., Rodolico C.

1

, Mazzeo A.

1

,Girlanda P.

1

, Vita G.

1

, Pizzuti A.

2

, Toscano A.

1

, Ajmar F., Mandich P.

Dept. of Oncology, Biology and Genetics, U. of Genova.

1

Inst. Neu-rol. Sci. and Neurosurg., U. of Messina.

2

Dept. of Neurology, U. ofMilano and C.S.S. I.R.C.C.S. San Giovanni Rotondo.

The clinical separation of CMT2 from HSAN I may bedifficult in some kindreds in which the sensory and motor

ABSTRACTS: Italian PNSG Journal of the Peripheral Nervous System 5:32–51 (2000)

33

symptoms and deficits are approximately alike. The geneticstudies of CMT2 families are also controversial: one form ofCMT2 was shown to map on chromosome 3q13-q22 andnamed CMT2B; the HSAN I locus was mapped to 9q22.1.We describe a family with an autosomal dominant inherit-ance in which at least three members, belonging to threegenerations, developed a progressive neuropathy that com-bined limb weakness, wasting, and severe distal sensoryloss leading to prominent mutilating changes. The onset wasin late childhood, with progressive weakness in the lowerlimbs and later in the hands, resulting in a severe paralysis inthe feet in one patient. Sensory disturbances were pro-nounced in 2 patients, and led to poorly healing ulcerationswith osteomyelitis and amputations in one foot and mutilat-ing lesions of both hands. Electrophysiological investigationrevealed an axonopaty with consistent motor damage. Suralnerve biopsy showed a reduction in the density of bothmyelinated and unmyelinated fibers, with regenerating clus-ters.

Linkage analysis using 5 microsatellite markers withinto the critical 9q22 region was performed. Lod scores of thisfamily calculated by LINKAGE package excluded associationto this locus. We also performed linkage studies with chr.3q13-q22 markers associated to the CMT2b locus. Lodscores excluded this locus as well as responsiblity of thefamilial phenotype. The severity of motor involvement wouldsuggest classifying the disorder of this family as a form ofHSMN II rather than HSAN, indicating that a new locus isinvolved in the pathogenesis of this disorder.

POSTIRRADIATION LUMBOSACRAL RADICULOPLEXOPATHY: IMPROVEMENT AFTER IMMUNE THERAPY

Bersano A., Carpo M., Di Troia A., Scarlato G., Nobile-Orazio E.

Institute of Clinical Neurology, IRCCS OspedaleMaggiore Policlinico, Milan University, Italy

A delayed progressive impairment of peripheral nervoussystem including brachial and lumbosacral radiculoplexopa-thy is a well-known complication of local radiotherapy. Notreatment for this infrequent complication is currently avail-able. Recently, improvement after treatment with high doseimmunoglobulin (IVIg) has been reported in some patients,suggesting either an immune-mediated inflammatory nervedamage induced by irradiation or a dysimmune neuropathy(CIDP-like) misdiagnosed as a postirradiation disease. Wereport on two patients who developed motor lumbosacralradiculoplexopathy several years after local radiotherapy. Thefirst patient (ZA) is a 49 y.o. man developing a progressiveproximal

.

distal weakness and hypotrophy of lower limbs,20 years after radiotherapy of lumbosacral region for semi-noma. Electrophysiological studies showed markedly reducedmotor conduction velocities (CV) and prolonged F-wavelatencies in lower limb nerves.

The second patient (BF), is a 52 y.o. woman who devel-oped progressive left brachial plexopathy and distal

.

proxi-mal weakness and hypotrophy of lower limbs 12 years aftera first course of toracoascellar and lumbar irradiation forHodgkin lymphoma followed by a second course of cervico-clavicular irradiation for tumor recurrence 7 years later. Elec-

trophysiological studies showed markedly reduced CMAPamplitudes and proportionally reduced CV in motor nerves.No sensory impairment was detected in both patients. CSFprotein was elevated in both patients while cells were nor-mal. On the assumption of a possible dysimmune origin ofthe disease, patient ZA underwent high dose intravenoussteroid treatment, while patient BF, who had previouslydeteriorated after steroids, was treated with IVIg. After treat-ment, patient ZA became able to walk with less waddling, torise from the floor and climb stairs without support, and torun. Improvement was less consistent in patient BF, whoseright leg strength improved even if she still needed bilateralsupport to walk. The improvement observed in both patientssupports the hypothesis that, at least in some patients, animmune-mediated mechanism may underlie postirradiationradiculoplexopathy.

MYELINATION DEFICIT IN NERVE OF SUCKLING RATS DUE TO CYCLOLEUCINE -INDUCED DEFICIENCY OF METHYL DONORS

Bianchi R., Baiguera L., Di stasi D., Tacconi M.T.

“MarioNegri” Institute for Pharmacological Research, Milan, Italy.

We used cycloleucine (CL) — which prevents methio-nine conversion to S-adenosyl-methionine (SAMe) by inhibitingATP-L-methionine-adenosyl-transferase (MAT) — to charac-terize the lipid and protein changes induced by methyldonors deficit in peripheral nerve and brain myelin in ratsduring development. We have previously shown that CL(400 mg/kg ip) given to suckling rats at days 7, 8, 12, and 13after birth reduced brain and sciatic nerve weight gain, brainmyelin content, protein, phospholipid (PL), and galactolipidconcentration in comparison to control. Among PLs, onlysphingomyelin (SPH) significantly increased by 35–50%.SAMe p-toluensulphonate (SAMe-SD4) (100 mg/kg, ip) givendaily from day 7, as with exogenous SAMe, partially pre-vented some lipid alterations induced by CL, particularlygalactolipid and SPH. To test the ability of CL to affect PLmetabolism we have measured

de novo

PL biosynthesis,

exvivo

in nerve homogenates (in comparison with brain homo-genates) from control and CL-treated animals killed at day 18after birth, starting from labelled substrates ([3H]-choline,specific activity 20 mCi/mmol) in a Tris/HCl buffer, containing5 mM MgCl2, 0.2 mM EDTA, 0.1 mM ATP, and 0.5 mM ofthe labelled substrates. After 60 min incubation, lipids wereextracted, PL separated by TLC, and corresponding silica gelfractions scraped and counted in a liquid scintillator. Phos-phatidylcholine enrichment in labelled choline resulted inslight increases in brain and sciatic nerve of CL-treated rats,suggesting an increased synthesis rate via the Kennedypathway, possibly due to the reduced availability of methyldonors. Interestingly, choline incorporation into SPH in brainand nerve myelin resulted in significant increases of 30–40%. In agreement with the observed decrease of galacto-lipid content and the relative increase in SPH, these datasuggest an alteration in sphingolipid metabolism after CL.

Among proteins, in sciatic nerves of CL-treated pups therelative content of a number of polypeptides, namely the116, 90, 66, 58, and 56 kDa bands, decreased, whereas oth-ers increased; the most abundant PNS protein, protein zero,


34

remained unchanged. The analyses of myelin basic proteinisoforms revealed a dramatic increase in the 14.0 and 18.5forms, indicating early active myelination. SAMe-SD4 treatmentcounteracted, and in some cases normalized, these changes.

In summary, methyl donor deficiency induced by MATinhibition produces myelin lipid and protein alterations, partlycounteracted by SAMe-SD4 administration.

The financial support of Telethon-Italy (grant No. D 51) isgratefully acknowledged.

THE INCIDENCE OF THE GUILLAIN-BARRE SYNDROME IN LOMBARDY, ITALY

Bogliun G., Beghi E. and Citterio A. for the Guillain-BarréSyndrome Registry Study Group.

Clinica Neurologica, Ospe-dale “San Gerardo”, Monza; Istituto “Mario Negri”, Milano.

The incidence of the Guillain-Barré syndrome (GBS)tends to vary between 0.4 and 4 cases per 100,000 popula-tion per year, depending on the size of the target population,the diagnostic criteria, and the accuracy of case ascertain-ment. In this study, the incidence of GBS was estimated forthe year 1996 by searching the affected individuals in a largegeographic area (Lombardy, population 8,924,870), usingstandard diagnostic criteria, and investigating multiple datasources. A case was included if he/she was a resident ofLombardy at the time of the diagnosis and there was mus-cle weakness and/or tendon areflexia with/without typicalCSF or EMG features. With reference to the Asbury criteria(Ann Neurol 1978; 3: 565), GBS was defined as typical oratypical. Excluded were patients with HIV infection, botu-lism, poliomyelitis, and dyphteria. The source of data includedthe hospital discharge diagnoses, a prospective GBS regionalregistry, and a concurrent case-control study. A total of 136cases met the inclusion criteria (regional registry, 87; hospi-tal discharge diagnoses, 45; case-control study, 4). The sam-ple included 72 men and 64 women aged 2 to 91 years. Theoverall crude incidence rate was 1.52 per 100,000 per year(95% CI 1.31–1.73) and the standardized rate was 1.51 per100,000 per year (95% CI 1.43–1.59). The rate was 1.71 inmen and 1.35 in women, and tended to increase with ageuntil 80 years (

,

40 yr, 0.87; 40–59 yr, 1.54; 60–79 yr, 3.06;80+ yr, 2.52). There were 10 patients with atypical GBS (cra-nial polyneuritis, 6; muscle weakness or tendon areflexia, 4).After excluding these cases, the incidence rate fell to 1.41(95% CI 1.20–1.61). Our study suggests that the incidenceof GBS in Lombardy, Italy, is fairly similar to that reported inthe most accurate surveys of the disease, and that multipledata sources must be investigated to provide an accuratecase ascertainment.

DOES LOSS OF MEDIAN NERVE FIBRES INFLUENCE SPONTANEOUS PAIN OCCURRING IN PATIENTS WITH SEVERE CARPAL TUNNEL SYNDROME?

Buonocore M., Bodini A., Mazzucchi G., Piazzoli S., Bag-nasco R.

Unit of Clinical Neurophysiology–Maugeri Founda-tion–Institute of Pavia–Italy.

Following peripheral nerve injury, a variety of mecha-nisms may generate and maintain pain. Pain mechanisms

occurring in entrapment neuropathies are largely unknown.Many studies have related peripheral neuropathic pain tonerve fibre dysfunction.

Aim of the study was to test the hypothesis of a possi-ble role played by the loss of nerve fibres in the pathogene-sis of pain occurring in patients with severe Carpal TunnelSyndrome (CTS).

Methods: Three consecutive patients (females) withsevere monolateral CTS but not spontaneous pain wereenrolled. Five females, age-matched control patients withsevere monolateral CTS and spontaneous pain, were alsorecruited. Severe CTS was confirmed by neurological exami-nation and classified by nerve conduction studies (absenceof peripheral sensory and motor evoked potentials). In orderto assess small-diameter fibres the Sympathetic Skin Response(SSR) evoked by auditory, alerting stimuli and recorded fromthe palm was also bilaterally tested.

Results: Patients with and without spontaneous paindemonstrated the same clinical pattern of nerve fibre dys-function. In particular, all patients had severe hypesthesia(tactile and vibratory) and hypalgesia (pinprick evaluation)over the second and third fingers (palmar surface), with anextension of sensory loss into the palm. Moreover, in allpatients, SSR was always bilaterally and symmetrically present.

Conclusion: These results failed to indicate a possiblerole of fibre loss (both large and small) of the median nervein the pathogenesis of pain occurring in patients with severeCTS. Different pain mechanisms, both neuropathic and noci-ceptive, may be simultaneously present in any one patient.Studies on a large population of patients are needed.

POSSIBLE USE OF SYMPATHETIC SKIN RESPONSEAND THERMOGRAPHY IN ASSESSING THE EFFECTSOF SYMPATHECTOMY: A CASE REPORT

Buonocore M., Bettaglio R.

1

, Bodini A., Miotti D.

1

, Maz-zucchi G., Bonezzi C.

1

Units of Clinical Neurophysiology and

1

Pain Therapy, IRCCS, Maugeri Foundation, Institute of Pavia -ITALY.

The objective assessment of sympathectomy is clinicallydifficult. Its success is usually judged in terms of patient’simprovement.

Aim: This study tested the hypothesis of possible use ofThermography and Sympathetic Skin Response (SSR) inassessing the effects of sympathectomy.

Case history: A man suffering from chronic, disablingpalmar hyperhidrosis underwent a bilateral, localised, endo-scopic resection of the thoracic sympathetic chain, immedi-ately below the second thoracic ganglion. After the operationhe had a significant reduction of palmar hyperhidrosis, buthe did not feel satisfied with the operation due to distal par-esthesias associated with thermal allodynia in the upperlimbs and excessive, troublesome compensatory sweatingof the trunk and lower limbs. We evaluated him fifteenmonths after the operation and symptoms were still present.Standard neurological examination was normal apart from amild heat hyperesthesia in the distal portions of upper limbs.

Methods: SSR was evoked by auditory, alerting stimuliand recorded simultaneously from palm and sole bilaterally.We preferred to use auditory stimulation because of the low


35

variability of SSR waveform usually obtained with this method.The amplitude of SSR in the palm and sole were measuredand a palm/sole ratio was calculated. Total body thermogra-phy was also performed.

Results: A clear reduction in SSR palm/sole ratio wasobserved. Thermography showed a thoracic thermal levelwith the upper part of the body being warmer than the lower.

Conclusion: Judging from the results obtained in thissingle case, both SSR and Thermography appear to be objec-tive, simple, noninvasive tools for assessment of thoracicsimpathectomy effectiveness. Studies on a large populationof patients are needed.

MAY ELECTROPHYSIOLOGY DIFFERENTIATE CHRONIC INFLAMMATORY DEMYELINATING POLYNEUROPATHY (CIDP) AND POLINEUROPATHY WITH ANTI-SGPG ANTIBODIES?

Capasso M., Torrieri F., Lugaresi A., Uncini A.

Center forNeuromuscular Diseases University “G. d’Annunzio” Chieti.

Demyelinating polyneuropathy with anti-MAG/SGPG abis elecrophysiologically characterized by a disproportionatedistal slowing of motor conductions. A terminal latencyindex TLI

5

0.25 in at least two nerves has been proposedto differentiate polyneuropathy with anti-MAG/SGPG ab fromother chronic demyelinating disorders (Kaku et al. 1994).

We reviewed and compared the electrophysiogicalstudies of 18 patients with CIDP and 8 with polyneuropathyanti-SGPG antibodies. The Anti-SGPG group showed: (1)lower CMAP amplitudes and longer motor distal latencies;(2) lower TLI and longer F wave latencies; (3) higher percent-ages of nerves with TLI

5

0.25; (4) much fewer conductionblocks; (5) more frequent absent SAPs.

CIDP and polyneuropathy with anti-MAG/SGPG seems tobe, as groups, electrophysiologically different. However, threepatients with CIDP showed at least 2 nerves with TLI

5

0.25and one, although displaying all the additional electrophysiolog-ical features characteristic of anti-MAG/SGPG polyneuropathy,was negative for ab search at diagnosis and one year later, anddid not have immunoglobulin deposits in sural nerve. On theother hand, one patient with anti-SGPG antibodies did not havedistal disproportionate slowing of motor conduction velocities.

In conclusion, demyelination seems to be in anti-MAG/SGPG polyneuropathy a length-dependent process, whereasin CIDP it tends to be patchy and multifocal, which strength-ens the view that these are two different pathophysiologicalentities. Electrophysiological findings can suggest an anti-SGPG polyneuropathy and address the search of ab, butthey are not pathognomonic in the individual patient.

COMPARISON BETWEEN A QUANTITATIVE CLINICAL SCALE AND NEUROPHYSIOLOGICAL EVALUATION IN CARPAL TUNNEL SYNDROME

Capone L., Gentile R., Schoenhuber R.

Department of Neu-rology –Regional Hospital 5 L.Boehler Str. – 39100 Bolzano.

Background: Carpal Tunnel Syndrome (CTS) is one of themost frequent cause of pain and paresthesias in the upperextremities. Neurophysiological studies allow to confirmdiagnosis based on clinical evaluation.

Aim of the study: to investigate if the score of the Simovicand Weinberg Clinical Scale (SWCS) for CTS correlates to theneurophysiological severity assessment proposed by Padua.

Material and methods: 65 consecutive patients with sus-pected CTS were examinated. 54 were females (mean age,54.5; range, 23–83). Body mass index (BMI), wrist circumfer-ence, and symptoms duration were also calculated for eachpatient. The SWCS was administered to all patients before neu-rophysiological evaluation. The scale consists of 11 items (8anamnestic and 3 clinical), which have a different impact on thetotal score (maximum 30/30). Diagnosis of CTS using SWCS canbe probable (9–30/30), possible (7–8/30), or unlikely (1–6/30). CTSwere classified using neurophysiological criteria according toPadua into six severity groups (from negative to extreme).

Results: CTS severity according to Padua’s criteria wasrelated to higher scores in SWCS. No correlation was foundcomparing BMI and symptoms duration with clinical andneurophysiological severity. Wrist circumference was alsonot significant. There was no diagnosis of unlikely-CTS atSWCS, but on the contrary 15 patients with probable CTShad no pathological findings at electrophysiological evaluation.

Comment: Clinical severity assessed using SWCS cor-relates with neurophysiological severity. Irritative symptomsare easily recognized by the SWCS, even if there is no neu-rophysiological correlate. The use of a sensitive scale asSWCS allows to avoid useless neurophysiological studies ifthe diagnosis of CTS is unlikely.

NORMATIVE VALUES OF THE MOST COMMON ELECTRONEUROGRAPHIC PARAMETERS IN PEOPLE AGED FROM SEVENTY FIVE TO NINETY

Capo G., Napoletano R., Esposito A.

Division of Neurology -Azienda Ospedaliera “S. Giovanni di Dio e Ruggi d’Aragona”Salerno, Italy.

The average lifespan is 78 years for women and 74 yearsfor men. By the year 2025, the average life expectancy for Ital-ians is estimated to reach 82 years. Today people aged 70 yearsor more will no longer accept illnesses as in the past. In our lab,the number of older outpatients referred for a neurophysiologi-cal tests is increasing continously. Patients above 75 years rep-resent 9% of the total number of our outpatients. Generally, thenormative values of the majority of the most common electro-neurographic parameters are available until a maximum age of75–80 years. We examined 49 patients (28 women and 21men). The examined parameters were motor nerve conduction(MNC) along median, ulnar, peroneal, posterior tibialis, axillary,and musculocutaneous nerves, and sensory nerve conductions(SNC) along median, ulnar, and superficial peroneal nerves.

A CASE CONTROL STUDY OF ANTI-GANGLIOSIDE AND ANTI-CAMPYLOBACTER JEJUNI ANTIBODIES IN GBS: CORRELATION WITH ANTECEDENT EVENTS AND WITH CLINICAL FEATURES

Carpo M.

1

, Bersano A.

1

, Citterio A.

2

, Allaria S.

1

, Cosi V.

2

,Nappi G.

2

, Scarlato G.

1

, Nobile-Orazio E.

1

and the WestLombardia GBS study group.

Inst. of Clinical Neurology,IRCCS Ospedale Maggiore Policlinico, Milan University

1

,and IRCCS C. Mondino Pavia

2

, Italy.


36

Anti-ganglioside antibodies have been reported fre-quently in Guillain-Barré syndrome (GBS), where they wereoften associated with an antecedent Campylobacter Jejuni(CJ) infection. To determine whether this association is alsopresent in an Italian population we implemented a case-con-trol study of GBS patients in Western Lombardia from 1996to 1998. We collected sera from 47 GBS patients in theacute phase (39 of whom were redrawn after three weeks),43 neurological controls (NC), and 41 non-neurological con-trols (NNC). Sera were tested by ELISA for IgG, IgM, and IgAantibodies to GM1, GD1a, GD1b, GM2, GQ1b, and to CJ.None of the anti-ganglioside antibodies tested was signifi-cantly more frequent in GBS patients during the acute phaseof the disease than in NC or NNC. All anti-ganglioside anti-bodies tested were more frequent during recovery than inthe acute phase, even if the difference was significant onlyfor anti-GQ1b IgG and IgM antibodies. The frequency of anti-GQ1b IgG was also significantly higher in convalescent GBSthan in NC and NNC sera. There was no correlation betweenthe presence of anti-ganglioside IgM antibodies in acutesera and IgG antibodies in convalescent sera. Anti-CJ IgGantibodies were only found in two acute GBS patients and inone NC. Both CJ-positive GBS patients had an antecedentdiarrhea and one also had high anti-GM1 IgG. An antecedentupper respiratory tract infection (URTI) but not diarrhea wassignificantly more frequent in GBS than in NC/NNC. URTI inGBS patients was not associated with a higher frequency ofanti-ganglioside antibodies than in NC/NNC. In conclusion, inthis study anti-ganglioside antibodies were not associatedwith GBS in the acute phase, but tended to increase duringthe course of the disease possibly suggesting a secondaryimmune response. This finding might reflect the low fre-quency of diarrhea and CJ infection in our GBS population,supporting the hypothesis of a regional variability in the etio-pathogenetic mechanism of GBS.

GDNF AND CISPLATIN NEURONOPATHY

G. Cavaletti

1,2

, E. Dondè

3

, P. Marmiroli

3

, G. Tredici

4

1

Clin-ica Neurologica, Dipartimento di Neuroscienze e TecnologieBiomediche, Università di Milano “Bicocca,” Ospedale S.Gerardo, Monza.

2

Istituto di Anatomia, Università di Milano,LITA, Segrate.

3

Istituto di Anatomia Umana, Università diMilano, Milano.

4

Sezione di Morfologia, Dipartimento diNeuroscienze e Tecnologie Biomediche, Università di Milano“Bicocca,” Monza.

GDNF is a growth factor produced in the central ner-vous system by glial cells and has a trophic action ondopaminergic neurons. However, GDNF mRNA is expressedalso in the dorsal root ganglia (DRG), suggesting that it mayact as a neurotrophic factor on different neuronal popula-tions. The three different GDNF receptor components arehighly expressed in a group of small primary sensory neu-rons and these neurons do not express any of the specific

Trk

receptors for the neurotrophins. Furthermore, GDNFreceptor expression has been also found in DRG neurons ofall sizes, indicating that these cells too may be responsive toGDNF. We have, therefore, evaluated the possible neuropro-tective effect of GDNF (1 mg/kg, s.c. three times a week,

donated by Amgen Inc) against cisplatin (CDDP, 2 mg/Kg i.p.twice a week for 9 times) DRG neuronopathy.

Using our experimental paradigm, GDNF had no posi-tive effect with both electrophysiological and morphometricdeterminations. The lack of GDNF activity in preventing thesigns of peripheral nerve involvement in CDDP neuronopa-thy with respect to NGF and NT3 may be explained by a dif-ferent distribution of their specific receptors in DRG neurons.In fact, the specific NT-3

Trk

C receptor is mainly expressedby the large DRG neurons, which are prominently involved incisplatin neuronopathy, while GDNF receptors are mainly,although not exclusively, expressed by small- and medium-sized DRG neurons. Small- and medium-sized DRG neuronsare also involved in the pathological changes of cisplatin neu-ronopathy, but to a lesser degree than the large ones. Further-more, GDNF, in other models of peripheral neuropathies, maybe active in an indirect way, mediated by its capacity to acti-vate macrophages and inflammatory responses.

LIPID-FREE VS. LIPID-BOUND EXPERIMENTAL ALLERGIC NEURITIS IN THE LEWIS RAT

G. Cavaletti

1

, S. Celon

2

, P. Marmiroli

2

, S. Matà

3

, A.Fasano

4

, F. Lolli

3

, P. Riccio

5

, G. Tredici

6

1

Department of Neu-rology, University of Milan “Bicocca”, S. Gerardo Hospital,Monza (MI).

2

Institute of Human Anatomy, LITA, Universityof Milan, Segrate (MI).

3

Department of Neurological and Psy-chiatric Sciences, University of Florence.

4

Department ofBiochemistry and Molecular Biology, University of Bari.

5

Department of Biology, DBAF, University of Basilicata,Potenza.

6

Institute of Human Anatomy, University of Milan“Bicocca,” Monza (MI).

The P2 protein of the peripheral nervous system myelinis a neuritogenic protein capable to induce experimentalallergic neuritis (EAN) in the Lewis rat. It has been sug-gested that addition of some lipids to the protein isolated inthe lipid-free form might enhance its immunogenicity.Because lipid-bound P2, copurified with all the myelin lipids,shows a conformation that is different from that of LF-P2,this difference might, in fact, influence its immunogenicity.

In this study, we have compared lipid-free P2

(the “EANfactor”)

with the corresponding lipid-bound form of the pro-tein for their ability to induce EAN after sc inoculation in theLewis rat.

The timing of disease and the clinical scores of lipid-bound P2-induced EAN animals (n

5

23) did not differ statis-tically from those injected with lipid-free P2 (n

5

23), withonly a tendency to higher clinical scores in the former group.Accordingly, tail nerve conduction velocities did not differ inthe 2 groups and were in both significantly lower in compari-son to Freund adjuvant controls (n = 8). Inflammation anddemyelination predominated in spinal roots and were lessevident in the sciatic nerve for both groups of animals. TheELISA determination of antibodies to lipid-free and lipid-bound P2 revealed the development of antibodies recogniz-ing the lipid-free form of the protein in both groups of animals.

Our results are in contrast with previous studies per-formed after addition of individual lipids to the P2 purified inthe lipid-free form, and indicate that native-like, lipid-bound P2is not significantly more immunogenic than lipid-depleted P2.


37

MACROPHAGE INFILTRATION AND INDUCTION OF P75 NTR AND IL-1B IN THE NERVE OF DIABETIC RATS

Conti G., De Riz M., Scarpini E., Bussini S.

1

, De Pol A.

2

,Vaccina F.

2

, Bianchi R.

3

, Livraghi S., Baron P., Stoll G.

1

,Scarlato G.

Institute of Neurology, Dino Ferrari Center,IRCCS Ospedale Maggiore Policlinico, University of Milan,Italy.

1

Department of Neurology, Heinrich-Heine-Universitat,Dusseldorf – Germany.

2

Dept. of Morphological Sciences,University of Modena, Italy.

3

Mario Negri Institute, Milan,Italy.

Recently, inflammation has been involved in the patho-genesis of diabetic neuropathy, and activated macrophageshave been found in the peripheral nervous system of dia-betic rats, with a possible role in chemotaxis and regenera-tion. In this study, we obtained sciatic nerve specimensfrom diabetic rats at different time points following STZadministration. Macrophages infiltration, IL-1b and p75NTRinduction were analyzed by immunocytochemistry on frozensections and on teased nerve fibers. Apoptosis wasdetected on teased nerve fibers by TUNEL and DAPI stain-ing. Cell phenotype was characterized by double-stainingwith antibodies specific for Schwann cells and macro-phages. The nerves obtained from STZ-diabetic rats showedmacrophages infiltration by day 14 following STZ administra-tion, with complete clearance by day 35. Fifteen percent ofthese cells were TUNEL positive. IL-1B induction was con-comitant with macrophages infiltration and not detectableby day 35. p75NTR expression began by day 21, peaking byday 35, and dropping to barely detectable levels by day 105.These findings seem to indicate that the concomitance ofthese processes may be crucial in the regulation of nervedamage and in promoting an attempt of regeneration at theearly stages of STZ diabetic neuropathy.

JUVENILE, AUTOSOMAL DOMINANT, DISTAL SPINAL MUSCULAR ATROPHY AND NEUROSENSORIAL DEAFNESS NOT LINKED TO CHROMOSOME 12q24

De Angelis M.V.

1

, Stuppia L.

1,2

, Passamonti L.

1

, Palka G.

2

,Gambi D.

1

Uncini A.

1

1

Center for Neuromuscular Diseasesand

2

Institute of Genetics, University “G d’Annunzio” Chieti.

Distal spinal muscular atrophy, also classified as a spinalform of Charcot-Marie-Tooth-disease, or distal hereditarymotor neuropathy, is genetically heterogeneous and bothautosomal dominant and autosomal recessive inheritancehave been described. Recently, in an autosomal-dominantBelgian family with juvenile onset in distal leg muscles, asignificant linkage was obtained with markers located atchromosome 12q24 (Timmermann et al. 1996).

We describe a three-generation Italian kindred with dis-tal spinal muscular atrophy showing autosomal dominantinheritance, onset at 8–10 years with leg weakness and atro-phy, later involvement of distal arm muscles, and eventuallyproximal muscles. The older patients also had neurosenso-rial deafness. To confirm the previous genetic findings, weused four microsatellite markers located at chromosome12q23-24: D12S86, D12S1612, D12S1349, PLA2A. No sup-port for linkage with 12q24 was found in this family, whichindicates a genetic heterogeneity in juvenile onset autoso-mal dominant distal spinal muscular atrophy.

ROSS SYNDROME: CLINICAL AND LABORATORY EVALUATION OF TWO CASES

De Joanna G.

1

, Perretti A.

1

, Tugnoli V.

2

, Nolano M.

3

,Cruccu G.

4

, Santoro L.

1

.

1

Department of Neurological Sci-ences, University of Naples “Federico II.”

2

Neurological Divi-sion, Arcispedale S.Anna, Ferrara

3

Maugeri Foundation,IRCCS, Telese (BN),

4

Department of Neurological Sciences,III Clin. Neurol. University of Rome “La Sapienza.”

We describe two males, aged 41 and 55, come to ourobservation complaining of heat intolerance, abnormal increasein body temperature with minimal exercising, reduced sweat-ing and, generalized fatigability; one of them had distal par-esthesias. Neurologic evaluation showed bilateral Adie’stonic pupil and an absence of deep-tendon jerks. A diagnosisof Ross’ Syndrome was advanced. Autonomic tests, nerveconduction study, H-reflex, computerized termoregulatoryand pain thresholds, laser CO

2

cortical evoked potentials, andskin biopsy were performed. One of them performed a his-tamine test and hand photopletismography resulted positivefor sympathetic impairment, and pilocarpine pupil test thatshowed a parasympathetic denervation hypersensitivity.

The following tests gave the same results in bothpatients: parasympathetic and most sympathetic tests werenormal. Sympathetic skin response was absent and Minortest showed an almost complete absence of sweating.Sweating was possible only in two or three small areas. Pos-itive pilocarpine test suggested a postganglionic involve-ment of sympathetic nervous system. Sensitive and motornerve conduction velocities were normal, while H-reflex wasnot detectable. Termoregulatory and pain thresholds wereabnormal. Laser CO

2

cortical evoked potentials showed theabsence of C fibre potentials, whereas A-

d

fibres responsewas abnormal in one of them. Hairy skin biopsy showed adefinite reduction of sweat glands and of small vessel inner-vation; glabrous skin biopsy performed in one of themshowed a reduced number of Meissner corpuscles. Thesefindings suggest that in Ross’ Syndrome the degenerativeprocess can involve, besides the autonomic fibres, myeli-nated somatosensory fibres also.

ANTI-GQ1b ANTIBODIES IN A PATIENT WITH FACIAL NERVE DIPLEGIA WITHOUT OPHTHAMOLPLEGIA

De Riz M., Clerici R., Carpo M., Siglienti I., Conti G., Scar-pini E., Baron P.L., Silani V., Cappellari A., Nobile-OrazioE., Scarlato G.

IRCCS Ospedale Maggiore, Dino Ferrari Cen-ter, University of Milan, Italy.

Anti-GQ1b IgG antibodies are detectable in patientswith Miller-Fisher syndrome and related to the developmentof ophthalmoplegia. We report a 56-year-old woman whowas admitted in our Hospital because of peripheral facialnerve diplegia, dysphagia, dysphonia, and areflexia twoweeks after a mild upper respiratory infection with fever.Gait with superficial and deep sensation appeared normal.Her mental status was intact. CSF, EMG, and MRI of the cer-vical spinal cord were normal, while GQ1b antibodies (1:1600), were found in the serum. Starting by day 4 afteradmission, the patient was treated with six plasma-exchanges,over a three-week period. By day 9, facial nerve diplegia,


38

dysphagia, and dysphonia started to improve. By day 35,there were no clinical deficits, and by day 45, deep tendonreflexes were elicitable again. Anti-GQ1b antibodies returnedto the normal range (1:800) six months later. Plasma exchangewas dramatically effective in the treatment of this patient.This clinical case shows that anti-GQ1b IgG antibodies maybe detectable in acute demyelinating polyradiculoneuropathywith bulbar signs and without ataxia and ophthalmoplegia.

SUB-CLINICAL PERIPHERAL NERVE INVOLVEMENT IN PSORIATIC ARTHRITIS

Di Girolamo C., Massini R., Lullo F., Crisci C.

“SalvatoreMaugeri” Foundation-Medical Centre of Telese T. (BN) Italy.

Immunological studies document the role of HLA inpsoriasis and the correlation between neuropeptides, psoria-sis, and related arthritis. Some anecdotal case reports,moreover, describe a noncasual association between periph-eral neuropathy and psoriatic manifestations. To verify a pos-sible subclinical peripheral nerve involvement in this disimmunepathology, we started a pilot study in twenty patients withpsoriatic arthritis and in whom other common causes ofperipheral neuropathies had been ruled out.

We performed a complete clinical neurological examina-tion and a neurophysiological examination (orthodromic sen-sory and motor nerve conduction velocity in median andtibial nerves; antidromic sensory nerve conduction velocityin sural nerve).

In 40% of the patients there was a mild but definite“glove-stocking” hypoesthesia, while hypopallesthesia wasdetected in only 20%. Electrophysiologic examinations wereless informative borderline distal conduction velocities in30% of patients.

These preliminary data suggest a peripheral nerveinvolvement in this pathology, mainly affecting the smallnerve fibres.

PERIPHERAL AND CENTRAL NERVOUS SYSTEM LYMPHOMA PRESENTING AS MULTIPLE CRANIAL AND PERIPHERAL RADICULONEUROPATHY

Di Troia A., Carpo M., Ghidoni P.

1

, Scarlato G., Nobile-Orazio E.

Institute of Clinical Neurology and Department ofPathology

1

, IRCCS Ospedale Maggiore Policlinico, Milan Uni-versity, Italy.

A 58 y.o. man was admitted to our hospital because ofsevere progressive untreatable radicular pain, limb weak-ness, and cranial nerve palsies. The patient was well until 2years before, when he developed progressive perineal sen-sory loss with impotence. Two months later, he complainedof pain in the right foot only partially responding to NSAIDs.A lumbosacral MRI showed a spinal stenosis and multiplelumbar discopathy. During the following year he developedright foot and left arm burning paresthesia only responsiveto oral opiates, left facial nerve palsy, right foot drop, armweakness partially responding to oral steroids, and cyclo-phosphamide. CSF and electrophysiological studies wereconsistent with an inflammatory multiple radiculoneuropa-thy while blood tests, bone scintigraphy, and abdominalechography were normal. Four months before admission, he

developed right wrist drop, painful dysesthesia in the lefthemithorax, and diplopia. On admission, neurologic exami-nation revealed left oculomotor and facial nerve palsies, dis-tal

.

proximal weakness in the extensor muscles of the rightarm, right foot drop, superficial and deep sensory loss onthe right leg, and ubiquitary absent deep tendon reflexes.Four additional spinal taps revealed markedly increased pro-teins with slightly increased cells (always below 10/mm

3

) butno tumor cell. Nerve conduction studies were consistentwith multiple radiculoneuropathy, while sural nerve biopsyshowed an axonal neuropathy. Bone marrow biopsy, chestand abdominal CT, and endoscopy of the gastrointestinaltract were negative for neoplastic lesions. A brain and cervi-cal MRI revealed multiple gadolinium enhancing hyperlucen-cies in the thalamus, caudate nucleus, and spinal cord. Thepatient was treated with intravenous steroids and IVIg withno response and with opiates for severe pain. One monthlater, the patient developed deep vein thrombosis treatedwith anticoagulants followed four days later by a fatal mas-sive intracranial hemorrhage. Autoptic studies revealed awidespread non-Hodgkin’s type B lymphoblastic centrociticlymphoma involving the stomach, liver, lung, thyroid, spleen,cauda equina, brain, and the spinal cord.

This report draws attention to the unusual presentationof a lymphoproliferative disease that escaped an extensivediagnostic evaluation during life.

X-LINKED DOMINANT CHARCOT-MARIE-TOOTH NEUROPATHY: ANALYSIS OF A PEDIGREE WITH A NOVEL MUTATION OF CONNEXIN 32

Fabrizi G.M., Polo A., Cavallaro T., Pinardi C., Taioli F., Corra’C., Rizzuto N.

Department of Neurological and Visual Sciences,Section of Clinical Neurology, University of Verona. Verona.

Objective: To report a family with X-linked Charcot-Marie-Tooth neuropathy (CMTX) with a novel mutation ofconnexin 32 (Cx32).

Background: Cx32, a gap-junction protein, is expressedin various neural and non-neural tissues. In the peripheralnervous system (PNS), Cx32 is expressed by the Schwanncell and it is believed to form reflexive gap-junctions at theSchmidt-Lantermann incisures and paranodes; in the centralnervous system, Cx32 is expressed by neurons and oligo-dendrocytes. Mutations of Cx32 causes an apparently tis-sue-specific disorder of PNS: CMTX.

Methods: We examined, clinically and electrophysiologically,2 brothers with CMT and their asymptomatic mother. We per-formed a sural nerve biopsy in the 29-year-old proband and analy-sed the Cx32 gene (GJB1) by direct nucleotide sequencing.

Results: We detected a novel GTA

→

GAA of GJB1 thatis predicted to cause a Val23Glu substitution in the firsttransmembrane domain of Cx32. NCV studies disclosed fea-tures of a demyelinating neuropathy in the severely-affectedhemizygous brother, and slowing of the sensory conductionvelocity in the sural nerve in the mother who showed pescavus and areflexia. In all three examined patients, BAEPsshowed both delayed wave 1 and prolonged interpeak-latency-time (IPL I-V); central motor conduction time byMEPs was normal. The nerve biopsy in the proband wasconsistent with a primary axonal degeneration.


39

Conclusions: Cx32 mutations may lead also to a dys-function of the CNS. Electrophysiological abnormalities ofthe CNS pathways may orientate the diagnosis of CMTtowards Cx32.

TRANSGENIC MOUSE MODELS OF CHARCOT-MARIE-TOOTH 1b

Feltri M.L.

1

, Quattrini A.

1

, D’Antonio M.

1

, Imperiale D.3,Dati G.1, Previtali S.1, Canal N.1, Messing A.2, Wrabetz L.1.1S. Raffaele Scientific Institute, DIBIT and Dept. of Neurol-ogy, Milan, Italy; 2School of Veterinary Medicine, Universityof Wisconsin, Madison, USA. 3Dept. of Neurology, Univer-sity of Turin, Italy.

We are creating transgenic mouse models of hereditarymotor and sensory neuropathy to address pathogenethicquestions. First, we are testing the hypothesis that some Pomutations act through gain of function, by expressing aCMT1b mutation, delSer34, in addition to two normal copiesof Po. We have shown previously that overexpression of wildtype Po causes dysmyelination in a dose-dependent fashion.Less than 50% overexpression of Po protein produces noeffect, whereas higher overexpression causes severe dys-myelination. We have produced 5 lines of delSer34 trans-genic mice that express the transgene at different levels,ranging from 5% to 300% of wild type Po. Lines thatexpress Po delSer34 below the 50% threshold show abnor-mal myelin sheaths containing metachromatic material insemithin sections. Lines that express above the 50%threshold show positive signs characteristic of CMT1b, like“onion bulbs,” together with signs typical of wildtype Pooverexpression. These myelin sheath abnormalities andonion bulbs are specific to mutant Po, as they were neverobserved in mice overexpressing wildtype Po. These prelim-inary results suggest that CMT1b mutations may have theireffect through a dominant negative or toxic mechanism. Inone line, mutant Po expression is roughly 50% of wildtypePo, a level comparable with one normal Mpz allele. This linewas crossed with heterozygous Po knock out mice to obtaina genotype (Po wt/2/PodelSer34) similar to that of a CMT1bpatient. These mice represent a potential model of CMT1b.

CRYOGLOBULINEMIC NEUROPATHY: A CLINICAL STUDY OF 25 CASESFerraris A., Marbini A., Giuberti T., Garini G., Allegri I.,Gemignani F. Istituto di Neurologia, Università di Parma -Parma.

Cryoglobulinemic neuropathy is probably the common-est form of vasculitic neuropathy, at least in SouthernEurope. We studied 25 patients (19 females, 6 males) withsymptomatic cryoglobulinemic neuropathy (HCV-related inall patients but 4) clinically evident, and confirmed by neuro-physiological study. Cryoglobulin was type 2 in 17 cases,type 3 in 4 cases, and not characterized in 4 cases. Neuropa-thy was more often in form of asymmetrical (mainly) sen-sory polyneuropathy (11 cases); other forms includedsymmetrical sensory polyneuropathy (8 cases), sensorimo-tor polyneuropathy (2 cases), and mononeuropathy multplex

(4 cases). Neuropathy was often the presenting manifesta-tion of the disease (16 cases), usually in association withpurpura (9 cases). Purpura was the commonest non-neuro-logical manifestation (21 cases), and was especially severein frequency and intensity in 11 cases. Purpura of relevantentity tended to be associated with more severe features ofneuropathy, on clinical and neurophysiological grounds, andworsening course. Severe purpura was more often associ-ated with asymmetrical neuropathy or mononeuropathymultiplex. Hepatic involvement, relevant in 7 cases and mildin 11 cases, did not correlate with the severity of neuro-pathic manifestations.

Peripheral nerve involvement in mixed cryoglobulinemiahas heterogeneous features, but factors conditioning itsexpression are poorly known. Our study suggests that theseverity of neuropathy is correlated with purpura thus thepathogenic mechanisms of cutaneous and neurologicalmanifestations may be interconnected.

NEUROPATHY AND S.L.E.(REVIEW OF THE LITERATURE AND PERSONAL RESULTS)Francia A., Restante R., Finamore L., Martini L., Vitale A.,Manfredi M. Department of Neurological Sciences, III Neu-rologic Clinic, University “La Sapienza,” Rome, Italy.

In 1950, for the first time, some authors described neu-ropathy in patients affected by SLE. This manifestation rarelywas described like a beginning symptom, its incidenceincreased during the last ten years (from 1% to 10%).

Pathogenesis is usually linked up to the evidence of vas-culitic lesions due to the presence of self-antibodies whichprecipitation produce vasa nervorum occlusion or promoterelasing of inflammatory factors.

Neuropathy has until now four well-known main mani-festations:

–Sensory-Motory Polineuropathy: the most frequentassonal, symmetric, distal, and subacute neuropathy.

–Radicular Neuropathy: with acute beginning, axonaland demielinating damage with a pathogenesis linkedup to the presence of Antifosfolipidi antibodies.

–Mononeuropathy Multiplex: it can be a SLE beginningsymptom, assonal, also with the involvement of cra-nial nerves.

–Autonomic Neuropathy: it can be isolated or it can beonly one manifestation of a wide nervous systeminvolvement.

Between Sept. 1998 and Dec. 1999, we studied 30patients affected by SLE; 5 patients presented a polineurop-athy prevalently sensitive, assonal, distal, involving fre-quently inferior limbs, which represents 16.6% of thepopulation.

Even if we think necessary an enlargment of the casis-tic, we consider appropriate to point to the increase of neur-opathy incidence in SLE patients, probably due to a neurologicalapproach. Immunological study of these patients usuallydoesn’t allow a correct evaluation of the peripheral nervoussystem involvment.

Therefore, peripheric and central nervous system com-plications of SLE must be considered important for thecourse of the systemic disease and for therapeutic choice.


40

A CASE OF “NORMAL” RADICULOPATHYFrancia A., Restante R., Finamore L., Barrella M., Man-fredi M. Department of Neurological Sciences, III Neuro-logic Clinic, University “La Sapienza,” Rome, Italy.

We followed up a woman, aged 58, presenting with dif-ficulty in fine finger movements, moderate-to-severe strengthdeficit at right thumb opposition, and ipsilateral thenar andhypothenar atrophy, but no pain or loss of sensibility. Aseries of electromyograms performed between November1996 and June 1997 pointed to motor polyneuropathy withconduction block. Lumbar puncture was negative and rou-tine blood chemistry showed erythrosedimentation rate tooscillate between normal and increased values. Antinuclearand antiendomysium autoantibodies were present, but anti-GM1 autoantibodies were negative. Cervical CT scanshowed right C5-C6 and C6-C7 foraminal stenosis supportedby joint hypertrophy.

The patient was subjected to intravenous immunoglob-ulin infusion and gluten-free diet with no improvement. Sub-sequent clinical follow up and electromyograms showed noconduction block or multiple motor involvement. A sus-pected diagnosis of round pronator syndrome was ruled outby neurophysiological data, clinical examination, and history.X-ray with oblique projections and magnetic resonanceimaging confirmed CT data. Currently, the same localiseddeficits persist, with no extension to other districts; a mildimprovement was seen after kinesiotherapy.

This case was complicated by initial misdiagnosis ofneuropathy of immunological origin, due to overestimationof nonspecific or isolated laboratory data. In this case, sim-ply focusing on X-ray data and greater attention to clinicalexamination and reported symptoms allowed a correct diag-nosis of “simple” cervical radiculopathy.

SENSORY MANIFESTATIONS IN CHARCOT-MARIE-TOOTH DISEASEGemignani F., Ferraris A., Alfieri S., Bellanova M.F., Mar-bini A. Istituto di Neurologia, Università di Parma–Parma.

Although positive sensory symptoms are classicallyconsidered a hallmark of acquired neuropathies, sensorymanifestations, in particular, pain, are not uncommon inCharcot-Marie-Tooth disease (CMT).

We investigated the occurrence of sensory manifesta-tions in 35 CMT patients (15 with CMT1, 20 with CMT2).

Positive sensory manifestations were reported by 18patients (51%), and were prominent in 7 patients (20%),representing an onset symptom and/or a main feature. Non-neuropathic (musculo-skeletal) pain was also frequent, occur-ring in 48% of patients. Comparison between CMT1 andCMT2 showed that positive sensory symptoms were signifi-cantly more frequent in CMT2 (70% versus 27%; p 50.018), representing a prominent clinical feature in 25% ofCMT2 patients. Non-neuropathic pain was more frequent inCMT1 (60%) than in CMT2 patients (40%), and representedan onset symptom and/or a main feature in 33% and 25% ofpatients, respectively.

Sensory manifestations in CMT seem more frequentthan previously thought, however their frequency may be

different in the genetic subtypes of the disease. The occur-rence of positive symptoms in CMT2 raises diagnostic prob-lems with regard to acquired axonal neuropathies, and, inparticular, chronic idiopathic axonal polyneuropathy (CIAP).Sensory symptoms, in particular, pain, may represent animportant issue in the management of CMT patients, espe-cially in a physical medicine approach.

COST-BENEFIT RATIO OF INTRAVENOUS IMMUNOGLOBULIN TREATMENT IN CHRONIC INFLAMMATORY DEMYELINATING POLYRADICULONEUROPATHY

Gragnani F.1, Ceschin V.1, Morino S.1, Clemenzi A.1, SosciaF.1, Gozzer M.2, Rusignuolo A.2, Antonini G.1. 1Departmentsof Neurosciences and 2Cellular Biotechnology and Hematol-ogy, University of Rome “La Sapienza,” Italy.

Intravenous immunoglobulin (IVIG) is considered an effi-cacious but expensive treatment in dysimmune polyneurop-athies. Nevertheless, to date, no studies have been conductedon the cost of this therapy. We retrospectively studied 21patients affected by chronic inflammatory demyelinatingpolyradiculoneuropathy (idiopathic-CIDP and CIDP-MGUS),comparing the clinical response and costs of IVIG therapywith those of plasma exchange (PE). Patients were treatedeither with IVIG (400 mg/Kg/die for five days) or PE (6exchanges in 3 weeks). Responders continued the sametherapy, which was progressively tapered down to one IVIGinfusion or one PE monthly. IVIG nonresponders received PEand vice versa. Patients were followed for a period rangingfrom 3 to 67 months (median: 29 months). The modifiedRankin disability scale was used to determine functionalimpairment at baseline and during treatment.

Eleven of 21 patients (52%) improved with the firstchoice of treatment. Of the remaining 10 patients, 3 bene-fited from the alternative treatment; 2 patients who did notrespond to the alternative treatment were again treated withthe first choice therapy and subsequently improved; 2patients on IVIG abandoned the therapy. One nonresponderto IVIG is currently receiving PE. The overall response rate tothe two therapies was similar. The mean cost per patientwas 1,128,000 lire/session for PE therapy (excluding equip-ment and medical staff costs) and 1,204,000 lire/dose forIVIG therapy. However, the responders to PE required alonger treatment than responders to IVIG.

ALTERED DOSAGE OF PERIPHERAL MYELIN PROTEIN 22 (PMP22) AFFECTS MYELIN PERIODICITY

Grandis M.1, Nobbio L.1, Abbruzzese M.1, Gherardi G.F.1,Bellone E.2, Ansaldo G.L.3, Mancardi G.L.1, and SchenoneA.1. 1Department of Neurological Sciences and Vision, Uni-versity of Genova. 2Department of Biology and Genetic, Uni-versity of Genova 3Department of Endocrinological Surgery,University of Genova.

PMP22 is a 22-kD glycoprotein expressed by myelinat-ing Schwann cells. PMP22 seems to play a dual role in regu-lating cell growth and in peripheral myelin compaction.


41

Myelin formation and maintenance are the result of interac-tions between PMP22 and the peripheral myelin proteinzero (P0), which form complexes at the myelin membraneand mutually contribute to stabilize the intraperiod lines andto held together the major dense lines. Both PMP22 and P0mutations result in specific inherited demyelinating neuropa-thies, which are neuropathologically characterized by uncom-paction of myelin lamellae and splitting of the major denselines in some myelinated fibers (MF). However, the mostcommon hereditary neuropathies, Charcot-Marie-Tooth 1A(CMT1A) and Hereditary Neuropathy with liability to Pres-sure Palsies (HNPP), are due to a duplication and a deletionrespectively, of the PMP22 gene, leading to over- and under-expression of the protein. It is unknown how the alteredPMP22 dosage impairs peripheral myelination. Using ourimaging system for nerve morphometry directly connectedto the electron microscope, we evaluated myelin lamellaeperiodicity in 150 MF from sural nerves of: 3 CMT 1A patients,3 HNPP patients, and 3 normal controls. Furthermore, wemeasured myelin period in 50 MF obtained from a CMT1Aculture model and in 50 MF from normal DRG cultures. Mye-lin periodicity was significantly increased in CMT1A patients(9.77 6 0.9 nm) and in the CMT1A culture model (10.1 6 0.1nm) compared respectively to the normal sural nerves (9.1 60.7 nm) and to the control cultures (9.6 6 0.1 nm). Con-versely, myelin periodicity was slightly reduced in HNPPpatients (8.9 6 0.7 nm).

In conclusion, PMP22 overexpression induces wideningof myelin lamellae, which may be recorded with appropriatemorphometric techniques. As this change has been alsoobserved in DRG cultures from a CMT1A rat model, it maybe the first stage of the demyelination process going on inthis disease. The observation that altered dosage of PMP22significantly affects myelin periodicity provides further cluesin understanding the role of this protein in the process ofmyelin assembly and maintenance.

PLASMA EXCHANGE VERSUS IMMUNOGLOBULIN INFUSION THERAPY IN MYASTENIC CRISIS.REPORT OF SIX CASESInghilleri M., Perinelli D., Gozzer M., Libertucci V., ConteA., Manfredi M. Department of Neurological Sciences andHematology University of Rome “La Sapienza,” Italy.

The clinical effectiveness of plasma exchange (PE) andintravenous immunoglobulin infusion (IVIg) were comparedin six patients during myastenic crisis. Five subjects hadautoimmune myastenia and one myastenia-like syndrome.Neurological examination showed low values of myastenicmuscle score. The initial treatment was infusion of IVIg 0.4gr/Kg/day for 5 days, but despite therapy, progressive dysp-nea and worsening muscular weakness appeared. After avariable delay from the last IG infusion (from 2 to 12 days)patients underwent PE treatment (Dideco Vivacell 798DESystem) for 8 days, receiving a daily, single-volume exchangewith 5% albumin replacement. After the fourth–fifth exchange,the patient weakness improved. Because PE started from 2to 12 days after the last IVIg infusion, the therapeutic effectof PE did not depend on a delayed IVIg action. A spontane-ous recovery also appears unlikely, because all the patients

had severe, progressive neurological symptoms that provedinsensitive to anticholinesterase drugs. A possible reasonwhy IVIg proved ineffective is that the various immunoglobu-lin preparations differed in the proportion of specific antibodyand therefore did not sufficiently counteract the patient’sautoantibodies. In agreement with this hypothesis, othershave recently described a remarkable post-exchange responseto IVIgs in a different dysimmune syndrome. PE was effec-tive because it directly washed the autoantibodies off.

In conclusion, these findings lend support to the use ofPE as first-choice treatment in patients in myastenic crisis.Infusion of IgIV should be given only when PE is unavailableor contraindicated and supportive therapy alone proves inad-equate.

ELECTRONEUROGRAPHY IN GUILLAIN-BARRE, SYNDROME (GBS): SENSITIVITY AND SPECIFICITYIuliano G., Mauro A., Esposito A. OO.RR. Salerno, Div. Neu-rologia, Salerno, Italy.

We assessed clinical sensitivity and specificity of differ-ent electroneurographic (ENG) parameters versus clinicaldiagnosis of GBS.

Clinical data of 24 patients affected by upper and lowerlimb neuropathy were revised. In all the patients the neuro-physiologic examination was performed according to theAAEM guidelines for GBS diagnosis. Fourteen patients (10males, mean age 47.9, range 13-70, and 4 females 71.5, 69–76) received a diagnosis of GBS. The non-GBS groupincluded nine males (59.11, 35–78) and one female (41years) with different neuropathies (3 diabetic, 2 alcoholic, 5unknown ethiology). Sensitivity and specificity of variousneurophysiologic parameters were calculated.

The single classical neurophysiological paremeters gavevariable values of sensitivity and specificity. The new vari-ables we introduced, Polineuropathy (diffusion of abnormalfindings and F-Wave latency) and Demyelination (distalmotor evoked potential amplitude and/or motor conductionblocks) gave the highest value of sensitivity and specificity,when associated.

ELECTROPHYSIOLOGICAL ABNORMALITIES IN DIABETIC PATIENTSLanzillo B. MD, Crisci C. M.D., Crispi F. MD, Saltalamac-chia A.M. “Salvatore Maugeri” Foundation, IRCCS, Rehabili-tation Institute of Campoli-Telese, Division of Neurology,Campoli (Benevento) Italy.

We studied 476 patients affected by diabetes: 166 male(mean age 61.6 6 10 years, range 27–91) and 310 female(mean age 61.5 6 8.4 years, range 25–82). Mean diseaseduration was 11.3 6 7.6 years, range 0.3–37).

All patients underwent surface motor and sensorynerve conduction along median, popliteal, and sural nerve.

Results. Median nerve: in 3.1% of subjects sensoryaction potentials (SAP) was absent; sensory nerve conduc-tion velocity (SNCV) was reduced in 41.8% in distal segmentand in 27.5% in the proximal segment. Motor nerve conduc-tion (MNCV) was reduced in 29.9% of the subjects.


42

Sural nerve: SAP was absent in 24.4% and SNCV wasreduced in 32.7%.

Popliteal nerve: MNCV was abnormal in 30.4% of thesubjects. Combining electrophysiological data we observedthat:

1. 28.6% of the subjects resulted normal2. 12.8% were affected by a lower limbs sensory neu-

ropathy3. 0.2% had a lower limbs motor neuropathy4. 5.9% had a lower limbs sensory-motor neuropathy5. 6.1% had a diffused sensory neuropathy6. 30.2% had a diffused sensory-motor neuropathy7. 16.2% had a carpal tunnel syndrome.

Patients were divided in 2 groups: patients with andpatients without neuropahy: the latter showed a significantlyshorter disease duration (12.7 6 8.1 vs 9.0 6 6.3; p , 0.0001).

In addition, we observed a significant correlation betweendisease duration and distal latency, median and poplitealMNCV, and SNCV in median and sural nerve (Regressiontest; p , 0.0001).

Patients on insulin showed a longer disease durationand more severe electrophysiological abnormalities.

MILD CARPAL TUNNEL SYNDROME: EARLY ELECTROPHYSIOLOGICAL DIAGNOSIS AND POST SURGICAL FOLLOW UPLanzillo B. MD, Nucciotti R. MD, Di Caprio G. MD, CrisciC. MD, Pappone N. MD, Saltalamacchia A.M., StancanelliA., Caruso G. MD1. “Salvatore Maugeri” Foundation, IRCCS,Rehabilitation Institute of Campoli-Telese, Division of Neurol-ogy, and 1Dept of Neurological Science, University of Medi-cine Federico II, Napoli Italy.

We studied orthodromic sensory and motor conductionalong median and ulnar nerves in 52 patients suspected forCTS (60 hands) and in 30 control subjects. Patients under-went electrophysiological examination before and up to 24months after surgical decompression.

We evaluated the following electrophysiological tests:

1. sensory nerve conduction velocity (SNCV) fromdigit III and V to wrist (dSNCV) and from palm towrist (pSNCV)

2. pSNCV/dSNCV ratio in median nerve3. median/ulnar pSNCV ratio4. Distal latency (DL)5. SNAP and CMAP amplitudes.

In 3 patients, presurgical neurographic findings were nor-mal. According to median dSNCV, the remaining 49 patientswere classified into 3 groups: A 5 normal, B 5 mild slowing,C 5 marked slowing. In all B and C group patients, medianpSNCV was significantly reduced. In group A, pSNCV wasreduced in 16 patients (53%), pSNCV/dSNCV ratio wasabnormal in 29 patients (97%), and median/ulnar pSNCVratio in all subjects (100%). DL, SNAP, and CMAP amplitudesabnormalities were detected only in group B and C. Diseaseduration in the 3 goups was inversely correlated with SNCVand DL abnormalities.

After surgery, neurographic findings returned within thenormal range earlier in group A, then in group B; group Cshowed an incomplete recovery of digit and palm SNCV at24 months.

Median palm/digit SNCV and median/ulnar pSNCV ratioswere the most sensitive tests, providing a reliable tool forthe assessment of very early phase of CTS and for the sub-sequent surgery treatment.

UNILATERAL SCIATIC NEUROPATHY OF THE TERMINAL BRANCHES, WITH ABNORMAL MRI OF THE NERVE AT THE THIGH

Lori S.1, Briccoli M.1, Zanfranceschi G.2, Fusi I.2 1Dept. ofNeurology, 2Dept. of Radiology, City Hospital, Prato, Italy.

A 52-year-old woman had a subarachnoid haemorrhagein 1996. No cause of bleeding was detected. After a hospitalstay of 2 months, the patient fully recovered, except for apersistent distal paralysis of her right lower limb. The patientis currently undergoing a reevaluation.

The knee jerks are slightly asymmetric dx . sn,whereas the right Achilles tendon reflex is lost. Atrophichypotonic paralysis of the muscles of the right leg is a prom-inent feature, with sparing of the thigh. Sensory loss is distrib-uted in leg’s sciatic area. Some tenderness is consistentlyappreciated with deep palpation of the posterior aspect ofthe thigh. EMG shows severe denervation of TA and calfmuscles on right, whereas ischio-crural muscles are bilater-ally normal. The latencies of MAPs from TA and gastrocnemius,evoked by nerve stimulation at the knee, are prolonged (.20msec). Sural nerve antidromic SAP is undetectable.

An MRI comparative study of the thighs has been per-formed (1.5 TESLA, SPIR suppression of fat tissue tech-nique, and MIP reconstructions for the nerve). The sciaticnerve imaging is sharply asymmetric. The left nerve is barelyvisible, as expected. On the right, one can see normal fas-cicular structure and no evidence of either extrinsic com-pression or hypertrophy. The unusual ease of imaging isascribed to increased water content, suggesting persistentedema and/or inflammation.

The hypothesis of ongoing activity of disease is consis-tent with the neurographic findings, but the cause andmechanism of nerve damage are not clear. The hypothesisof a compartment syndrome may be suggested by the his-tory of coma, but the selective distal damage is not easilyexplained on this basis.

AN INNOVATIVE HAND BRACE FOR TREATMENT OF CARPAL TUNNEL SYNDROME (CTS): RESULTS OF A CONTROLLED STUDY

Manente G.1,2, Torrieri F.1, Di Blasio F.2, Uncini A.21Division of Neurology, Hospital of Vasto, 2 Center for Neuro-muscular Diseases, University “G. d’Annunzio” Chieti.

We recently noticed that squeezing the distal heads ofmetacarpal bones (excluding the first) and stretching the IIIand IV finger relieved paresthesias and pain in CTS (Manenteet al. 1999). This manoeuvre was the rationale to design an


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innovative hand brace we called “MANU” (patented) and todesign a trial to assess efficacy and tolerability.

Forty patients with CTS symptoms and abnormal elec-trophysiological tests were instructed to wear MANU duringthe night for 1 month. Efficacy was assessed by the Levinescale the Subject’s Global Impression of Change Question-naire. Forty CTS patients served as control.

In the MANU group, the Levine score was at the entry:2.3 6 0.6 and 1.5 6 0.5 at the end of the study (p , 0.001).At 1 month 27 patients (67.5%) were free of symptoms orreported pronounced improvement, and 13 (32.5%) reportedmoderate or mild improvement. MANU was very well toler-ated by all patients. In controls, Levine score was at entry 2.4 60.6 and 2.3 6 0.6 at the end (p 5 0.6). At 1 month, 7 patients(17.5%) reported mild or moderate improvement (4 patientsspontaneously, 3 after change or reduction of manual activi-ties), 33 patients (82.5%) reported no change or worsened.

This short-term study shows that MANU is highly effi-cient in ameliorating CTS symptoms and well tolerated.

CMT1A ASSOCIATED WITH 17p11.2 DUPLICATION AND ASYMMETRICAL LEG MUSCLE HYPERTROPHYManganelli F., Orsini A., Iadicicco L., Santoro L. Depart-ment of Neurological Sciences, University of Naples “Feder-ico II”.

Charcot-Marie-Tooth disease (CMT) is the most com-mon inherited disorder of the peripheral nervous system. Itis characterized by distal muscle weakness and atrophy, firstinvolving legs and particularly the peroneal muscles with thetypical leg as “inverted champagne bottle”.

The CMT1A is an autosomal dominant demyelinatingsensorimotor neuropathy most often associated with aduplication of chromosome 17p11.2, a region that containsthe gene for the peripheral protein 22 (PMP22). We describetwo families with CMT1A, in which three of six membersdid not show the typical feature of leg atrophy. In fact, apatient belonging to the first family showed a bilateral sym-metric hypertrophy of the calf. In the second family, a patienthad an asymmetric bilateral calf hypertrophy, and his sonshowed a similar condition but the asymmetric hypertrophyinvolved the whole left limb. The other cardinal features in ourfamily were distal weakness of lower limbs (5 of 6), pescavus (3 of 6), and reduced or absent tendon reflexes (6 of 6).

Motor and sensory conduction velocities showed, in allnerves explored, values at or below 38 m/sec. The computedtomography of lower limbs showed that leg enlargement wasdue to true muscle hypertrophy without concomitant increaseof adipose or connective tissue.

The pathophysiological mechanisms responsible formuscle enlargement are yet unclear. It is possible that oneor more genetic factors, still unknown, may be linked genet-ically to the neuropathy in such pedigrees in which most orall affected members carry the trait.

CIDP: DESCRIPTION OF FOUR PARTICULAR CASESManganelli F., De Joanna G., Bruno R., Santoro L.Department of Neurological Sciences, University of Naples“Federico II”.

Chronic inflammatory demyelinating polineuropathy (CIDP)is an acquired polineuropathy, clinically heterogeneous, andis associated with demyelination of spinal roots and periph-eral nerves with a monophasic, progressive or relapsing course.

We describe four patients affected by CIDP with differ-ent clinical pictures.

The first patient, a 54-year-old man, complained of a 10year paresthesia, with a slight wasting and weakening of theright leg, where he showed the absence of deep tendonreflexes and a reduction of the vibration sense.

The second patient, a 21-year-old woman, had distal par-esthesia and mild weakness restricted to the left hand.Deep tendon reflexes were reduced and vibration sensewas normal.

The third patient, a 41-year-old man, with a 5 year his-tory of muscle cramps more frequent in the upper limbs,showed mild weakness of the right forearm, absence of dis-tal deep tendon reflexes, and a reduction of vibration sensein the lower limbs.

The last patient, a 20-year-old man, showed a markedincrease of CPK level, a severe and progressive proximal anddistal hypotrophy in the upper and lower limbs, and respira-tory distress. Deep tendon reflexes were absent.

Nerve conduction studies showed a reduction of sen-sory and motor velocity, which was not homogeneous amongthe patients and among the explored nerves of each patients.Proximal motor conduction blocks were present only inthree cases. CSF parameters were normal and antibodiesanti nerve were absent in all patients.

The first three patients were treated with IVIg with aclear clinical and electrophysiological improvement, the lastpatient showed a moderate improvement, only after cyclosporinA treatment.

These four cases confirm that CIDP is clinically hetero-geneous with a variable spectrum of symptoms and sever-ity, from a minimal clinical evidence to a severe clinicalpicture as in our fourth patient.

VASCULITIC NEUROPATHY - 8 YEARS FOLLOW-UP STUDY ON PATIENTS ADMITTED TO HOSPITALMartini L., Francia A., Vitale A., Finamore L., Manfredi M.Department of Neurological Sciences, III Neurologic Clinic,University “La Sapienza”, Rome, Italy.

International literature doesn’t succeed in clarifing bothclinical features and epidemiologic importance of isolatedand nonisolated (associated with a systemic disease) vascu-litic neuropathy.

During a three years period (1990–1993), 284 patientsaffected by peripheric nervous system disease were admit-ted, as Day Hospital patients or like ordinary hospitalization,into the III Clinic of Neurologic Science Department at “LaSapienza” University-Rome. Seventy-two patients in ourgroup were affected by polineuropathy.

From an epidemiologic point of view, only 5–6% of pop-ulation conformed with vasculitic polineuropathy diagnosticcriteria; this percentage comprises equally systemic and iso-lated vasculopathy. After first admission, patients underwentclinical and instrumental checks through which modificationsof nosographic classification were recordered.


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At the end of the study period, in 1998, 13.8% of patientshad a vasculitic neuropathy diagnosis expressed: 70% dur-ing systemic disease, 30% as isolated vasculopathy ofperipheral nervous system. Simultaneously with the increaseof vasculitic neuropathy, we noted a considerable decreaseof cryptogenetic neuropathies, the incidence of which changedfrom 30% to 22%.

Diagnostic evaluations more suitable for nosographicchange seem to be:

• Clinical and Neurophysiological monitoring• Sierologic and cerebral spinal fluid monitoring• Histologic examination of the nerve• Evaluation of systemic involvment and of its peculiar

features that, in our experience, is frequently difficultto frame.

Our results do not differ greatly from those found in interna-tional literature and confirm the need of a detailed follw upfor a proper nosographic classification.

EXPRESSION OF TENASCIN-C IN THE SURAL NERVEOF PATIENTS WITH INHERITEDDEMYELINATING NEUROPATHIES

Massa R., Palumbo C.1, Bernardi G., and Modesti A.1

Departments of Neurosciences and Experimental Medicine1,Università di Roma-Tor Vergata, Roma.

Tenascin-C (TN-C) is an extracellular matrix glycoproteinsynthesized by glial cells that is involved in neuron–glia inter-actions. During development of peripheral nerve (PN), TN-C isabundantly expressed by myelinating Schwann cells, while inthe adult its synthesis is down-regulated and its localizationrestricted to the node of Ranvier in myelinated nerve fibers.

Interestingly, TN-C expression is up-regulated in the PNof some animal models of inherited human demyelinatingneuropathies. Moreover, in TN-C-deficient mice, importantmorphological alterations of PN have been demonstrated.

We have therefore studied the expression of TN-C insural nerve biopsies of patients with inherited demyelinatingneuropathies such as CMT1 and HNPP, using immunoperox-idase and immunofluorescence methods. At variance withcontrol nerves, where TN-C immunoreactivity was localizedonly in the perineurium and at the node of Ranvier, in allpathological nerves TN-C was present also in a variable num-ber of Schwann cells and myelin sheaths, sometimes mark-ing whole myelin internodes.

These data suggest that TN-C expression by Schwanncells in human pathologic nerves may be a marker of activedemyelination and/or remyelination. These events may bemodulated by TN-C by mediating adhesive interactionsbetween axons and Schwann cells, in a way similar to thatobserved in the developmental stage.

E-CADHERIN AND b-CATENIN COMPLEX IN ANIMAL MODELS OF HEREDITARY DEMYELINATINGPERIPHERAL NEUROPATHYMenichella D.M., MD, Baron P.L., MD., PhD., Livraghi S.,Conti G., MD., Scarpini E., MD and Scarlato G., MD.Dept. of Neurology, “Dino Ferrari” Center, University of Milan.

E-cadherin, a major adhesive glycoprotein in Schwanncells (Fannon et al., 1995), is localized at the paranode, atSchmidt-Lanterman incisures in the peripheral nerve alongwith b-catenin, and associated with adherens-type junc-tions. To investigate the functional role of E-cadherin/b-catenincomplex in Schwann cells biology, we studied expressionand localization of E-cadherin and b-catenin complex in sciaticnerve from normal mice and from animal model of heredi-tary demyelinating peripheral neuropathy.

We found that E-cadherin mRNA and proteins levels areregulated in normal mouse sciatic nerve during develop-ment like other myelin proteins. Furthermore, E-cadherinexpression in regenerating nerve is mediated by axonal/SCinteraction. On the contrary, b-catenin mRNA and proteinlevels did not change during development and followingnerve lesion. Moreover, E-cadherin/b-catenin complex local-ization is altered in P0 knockout mice (P0-/-). In fact, E-cad-herin was diffusely distributed throughout the fibers in anunusual beaded pattern of staining, and b-catenin was foundin the perinuclear region of P0 -/- Schwann cells.

Furthermore, E-cadherin/b-catenin complex localizationis altered in peripheral nerve from other model of primarydemielination where myelin compaction is lacking, such asTrembler-J mice, while it is normally localized in Tremblermice, where demyelination is less severe and compaction ispreserved.

In conclusion, it appears that the process that leads to arestricted localization of E-cadherin at the paranodal region ishighly regulated and is disrupted in the peripheral nerve lack-ing compaction.

Therefore, compaction contributes to the process ofreorganization of the Schwann cells membrane during myeli-nation and formation of a mature paranode. Altered E-cad-herin/b-catenin complex localization, associated with absenceof adherens junctions lead to changes in the structure of theparanodal region with important consequences on themolecular architecture of the Node of Ranvier, which lead toan altered transmission of impulses along axons, havingimportant consequences in the pathogenesis of hereditarydemyelinating peripheral neuropathy.

PACLITAXEL NEUROTOXICITY: ANTI-APOPTOTIC EFFECT OF RESVERATROLMiloso M.1, Rigolio R.1, Nicolini G.1, Crimi M.1, Donzelli E.1,Di Silvestro A.1, Cavaletti G.1, 2, Tredici G 1, 3. 1Istituto di Anato-mia, Università di Milano, LITA, Segrate. 2 Clinica Neurolog-ica, Dipartimento di Neuroscienze e Tecnologie Biomediche,Università di Milano “Bicocca”, Ospedale S. Gerardo, Monza.3 Sezione di Morfologia, Dipartimento di Neuroscienze e Tec-nologie Biomediche, Università di Milano “Bicocca,” Monza.

We have demonstrated in the SH-SY5Y human neuro-blastoma cell line that the antineoplastic drug paclitaxelinduces apoptosis associated with the phosphorylation ofc-raf and Bcl-2, thus causing Bcl-2 inactivation. In addition,we have observed the cleavage of caspase 7 and PARP, andthe involvement of JNK/SAPK cascade.

In this study, we investigated the possible anti-apoptoticeffect of resveratrol on paclitaxel-induced apoptosis. Resver-atrol is a natural antioxidant occurring in grapes and wine


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that as been shown to have anticancer and anti-inflamma-tory effects. Studies on the effect(s) of resveratrol on ner-vous cells are very few and limited to testing its ability inpreventing oxidative stress in rat pheocromocytoma PC12cells. However, the biological and pharmacological proper-ties of resveratrol suggest that this natural compound mightact on neuronal cells with a mode of action that is differentfrom the antioxidant ones. To confirm this hypothesis, westudied the possible antagonist effect(s) of resveratrol onpaclitaxel-induced apoptosis pathways.

Our results indicate that the simultaneous treatment of50M resveratrol and 1M paclitaxel induces a significantreduction of the percentage of apoptotic cells in comparisonwith 1M paclitaxel alone. Furthermore, we have demon-strated that resveratrol treatment determines a significantreduction of the phosphorylation of c-raf and Bcl-2 and a par-tial reduction of cleavage of caspase 7 and PARP. Finally, weobserved an evident reduction of activation of JNK/SAPK inthe presence of resveratrol. On the contrary, resveratrol doesnot affect the tubulin polymerization induced by paclitaxel.

In conclusion, our results suggest that resveratrol is ableto partially antagonize a nonoxidative stress apoptotic stimulusby influencing the typical signal pathways involved in apoptosis.

HYPERTROPHY OF SPINAL ROOTS IN CHRONIC INFLAMMATORY DEMYELINATING NEUROPATHY

Nardelli E., Agazzi P., Polo A., Boaretto M.1, Cavallaro T.,Ferracci F.2, Moretto G.2 and Rizzuto N. Department of Neu-rological and Visual Sciences, Section of Clinical Neurology,University of Verona, Verona, Italy. Departments of Medicine1

and of Neurology2, Ospedale di Belluno, Belluno, Italy.

We report on two patients (A, B) who developed unusualhypertrophy of cervical (A; disease duration (dd), 21 months)or lumbar (B; dd, 12 months) roots (LR) causing clinical fea-tures that were interpreted elsewhere initially as neurofibro-mas (A) or a Guillain-Barrè syndrome (B). Nodular swellingsalong radial, ulnar, and the great auricular nerve wereobserved (A). Clinical signs of a rapid mixed motor and sen-sory distal impairment of all four limbs were occasionallyassociated with signs of spinal epiconus compression (B). Ashort course of 500 mg methylprednisolone/day for fivedays was administered without benefit (B). The clinical sta-tus rapidly improved with intense course of IVIg (B). Thelevel of CSF protein was raised (B). Electrophysiologicalstudies showed an impairment of both peroneal and tibialNCV overall through the proximal segments (prolongedF-wave latency in A and B) and conduction blocks (A). Atten-uated peripheral SNAPs (sural nerve, B) and absent spineand scalp SEPs from lower limbs (B) were found. Sural nervebiopsy (A) showed massive presence of onion bulbs through-out the section. Case A appears to fall somewhere betweenmultiple mononeuropathy with persistent conduction blocksand CIDP. Case B had a relapsing-remitting course and occa-sionally myelopathy insidiously appeared. Paraparesis due tothe compression by enlarged and hypertrophic roots at thecauda equina was radiologically evident. MRI together withelectrophysiological studies, and treatment response maybe necessary to establish a correct diagnosis (A and B). The

frequency of root hypertrophy (57% in Duggin’s series, Brain122, 1383, 1999) probably deserves further clinical studiesand observations in the animal models of CIDP.

TAXOL NEUROTOXICITY: CELLULAR MECHANISMS INVOLVED IN APOPTOSISNicolini G.1, Saccomanno D.1, Scuteri A.1, Rigamonti L.1, 2,Galbiati S.1, Miloso M.1, Cavaletti G.3, Tredici G.1, 2. 1 Isti-tuto di Anatomia, Università di Milano, LITA, Segrate. 2 Sezi-one di Morfologia, Dipartimento di Neuroscienze eTecnologie Biomediche, Università di Milano “Bicocca”,Monza. 3 Clinica Neurologica, Dipartimento di Neuroscienzee Tecnologie Biomediche, Università di Milano “Bicocca”,Ospedale S. Gerardo, Monza.

The antineoplastic drug paclitaxel (Taxol™) is neurotoxicon the peripheral nervous system. Both activity and neuro-toxicity of paclitaxel are due to enhancement in tubulin poly-merization. In addition, it has been demonstrated thatpaclitaxel induces gene expression. To elucidate the signaltransduction pathways involved in paclitaxel neurotoxicitywe studied in vitro the effect(s) of paclitaxel on the humanneuroblastoma (HN) SH-SY5Y cells, which express genesassociated with neuronal differentiation and may be consid-ered neuroblasts at various stages of maturation.

The exposure of SH-SY5Y cells to paclitaxel producesapoptosis, as demonstrated with Annexin V assay andorange acridin staining. Electron microscopy showed typicalcondensation of nuclear chromatin with normal nuclearmembrane. DNA electrophoresis confirmed the occurrenceof apoptosis by demonstrating the typical laddering.

We studied regulator proteins as Bcl-2 and c-raf, andinvestigated the classes of caspases activated in this pro-cess by immunoblotting. We observed that 1mM paclitaxelinduces a simultaneous phosphorylation of c-raf and Bcl-2,thus causing Bcl-2 inactivation. Caspase 3, which is com-monly present and activated in the nervous cells, was notactivated, while paclitaxel-induced apoptotic process in SH-SY5Y cells is induced by activation of caspase 7. The involve-ment of caspase 7 is also confirmed by the same pattern ofcleavage of PARP. Finally, we also studied MAPKs, a familyof serine/threonine kinases that represent key signaling pro-teins known to be involved in many cellular events, includingapoptosis.

Our results indicate that paclitaxel does not activateERK cascade, whereas it induces JNK/SAPK and p38 phos-phorylation, suggesting that these specific pathways areinvolved in the cell-death induced by paclitaxel.

CLINICAL AND IMMUNOLOGICAL FEATURES AND RESPONSE TO IVIg IN PATIENTS WITH CLINICALLY TYPICAL MULTIFOCAL MOTOR NEUROPATHY BUTNO OVERT CONDUCTION BLOCKNobile-Orazio E., Meucci N., Terenghi F., Bersano A., Cap-pellari A., Carpo M., Barbieri S., Scarlato G. Institute of Clin-ical Neurology, IRCCS Ospedale Maggiore Policlinico, MilanUniversity, Italy.

Multifocal motor neuropathy (MMN) is characterized byprogressive asymmetric limb weakness usually predominant


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in the upper limbs associated with conduction block (CB) inmotor but not sensory nerves. There are, however, occa-sional patients with clinically typical MMN in whom no CBcan be detected. Whether these patients differ frompatients with MMN and CB remains unclear. Since 1991, wehave observed 24 patients with the typical clinical featuresof MMN. In 20 of them (14 men and 6 women), electrophys-iological studies disclosed the presence of CB in at least onemotor nerve. In four (all women), no evidence of CB couldbe detected in examined nerves even if three had some fea-tures of demyelination, including asymmetric reduction ofmotor conduction velocities (1 patient) or prolonged orabsent F wave latencies (3 patients). Three of them hadmarkedly reduced or absent proximal and distal CMAPamplitudes in some nerves. The mean age of onset of MMNwas similar in patients with (41.5 years, range 21–70) andwithout CB (41.5 years, range 24–57). The mean duration ofthe disease at the time of our first visit was longer inpatients without CB (18.5 years, range 13–25) than in thosewith CB (6.3 years, 3 months–25 years); only 3 patients withCB had a duration of the disease longer than 10 years. Allpatients without CB had a predominant or exclusive impair-ment of upper limbs compared with 18 (90%) of those withCB. The mean Rankin score before therapy was slightlyworse in patients without (2.5) than with (2.2) CB. Anti-gan-glioside antibodies were found in 1 patient without CB(25%) and in 8 (40%) with CB. All but 2 patients with CB(90%) consistently improved with IVIg. All patients withoutCB also improved with IVIg, but only one did so consistently.In conclusion, patients with the typical clinical presentationof MMN but no overt CB are clinically and immunologicallyindistinguishable from those with MMN and CB. The longerduration of the disease and frequent axonal impairment inpatients without CB may explain the lower efficacy of IVIg inthese patients than in those with CB.

QUANTITATIVE SENSORY TESTING AND SWEAT FUNCTION IN FRIEDREICH’S ATAXIA. CORRELATION WITH CUTANEOUS INNERVATIONNolano M., Provitera V., Crisci C., Saltalamacchia A., FillaA.1, Wendelshafer-Crabb G.2, Kennedy W.R.2, Santoro L.1,Caruso G.1 “Salvatore Maugeri” Foundation – Medical Cen-tre of Telese T. (BN) Italy. 1Dept. of Neurological Sciences,University of Naples “Federico II”. 2 Dept. of Neurology, Uni-versity of Minnesota, Minneapolis (MN) USA.

To evaluate small fiber function in Friedreich’s Ataxia(FA), we performed in 7 patients pin-prick, thermal thresh-olds, and sweat test. All tests were performed in four differ-ent sites: hand dorsum, anterior thigh, lateral distal leg, andfoot dorsum. The same subjects underwent 3 mm punchskin biopsy from fingertip, anterior thigh, and lateral distalleg. We used a thin needle mounted on a calibrated nylonwire for the pin-prick test, and a Medoc 2001 TSA system forthermal threshold assessment. Sweat test was performedusing a silicon mold after stimulation with pilocarpine by ion-tophoresis.

Skin specimens, cut into 100-mm-thick sections, weredouble-stained using primary antibodies specific for collagenand nervous fibers and secondary antibodies labeled with

Cy3 and Cy5 fluorophores. Tridimensional digitized imageswere obtained from z-series of 2-mm-thick optical sectionsacquired with a confocal microscope.

We found in all patients in the more distal sites definitesigns of functional impairment of the small fibers. Thesedata correlated with the skin innervation morphological find-ings that showed, in the same sites, a sensible loss of smallfibers regarding both the epidermal free endings and thesubepidermal neural plexus. Less severe morphologicalabnormalities were found in the proximal sites.

The large fiber neuropathy in FA is well documented.Our data show a length-dependent involvement of smallfibers in the pathological process.

AN OPEN STUDY OF RILUZOLE VERSUS RILUZOLE PLUS GABAPENTIN IN AMYOTROPHIC LATERAL SCLEROSISPalma V, Brescia Morra V, Polverino M, Santoro L, CarusoG. Dept. of Neurology, Federico II University, Service ofNeurophysiopathology, Nuovo Pellegrini Hospital, Naples,and Service of Respiratory Physiopathology, Cava dei TirreniHospital, Italy.

A randomised open study has been carried out to evalu-ate the efficacy of riluzole versus riluzole plus gabapentin in50 patients (23 males, 27 females) affected by amyotrophiclateral sclerosis (ALS), who received the diagnosis accordingto El Escorial WFN criteria. At baseline, the mean age of thepatients was 58.8 6 11.7 years and the mean disease dura-tion was 11.4 6 5.9 months. Twenty patients had bulbar and30 spinal onset. Twenty-eight patients were randomlyassigned to riluzole (100 mg/day) and 22 to riluzole plusgabapentin at the initial dose of 300 mg/day, slowlyincreased to 1800 mg/day. Informed consent was obtainedin all cases. Before treatment, each patient underwent neu-rological examination, Appel rate scale, pulmonary functiontests, electromyography, and transcranial magnetic stimula-tion. Clinical examination and electrophysiologic tests wererepeated at three-month intervals. Over the course of thetrial, 4 patients (8%) were lost to follow-up and 16 (32%, 9 inthe riluzole and 7 in the riluzole plus gabapentin group) died.The mean age at death was 65.0 6 6.5 years after a meandisease duration of 20.8 6 7.9 months (range 13–36). Therewas no significant difference in response to treatment whenseverity and duration of the disease were compared in thetwo groups.

ATYPICAL DEMYELINATING CHARCOT-MARIE-TOOTH DISEASE AND MYELIN GENE MUTATIONSPareyson D., Sghirlanzoni A., Botti S., Lauria G., Ciano C.,Morbin M., Taroni F. National Neurological Institute “C.Besta”,Milan, Italy.

Among our series of patients with inherited demyelinat-ing neuropathies, we identified families showing atypicalfeatures and carrying mutations in myelin genes. Weobserved two sibships with Dejerine-Sottas disease born toconsanguineous parents both affected by a mild Charcot-Marie-Tooth neuropathy with only slight nerve conductionshowing (.40 m/sec in upper limbs). The children carried ahomozygous frameshift mutation in the P0 gene (Val102fs)


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resulting in a nonfunctional protein truncated very early inthe extracellular domain. The parents, harboring the muta-tion in heterozygous form, had a distinct phenotype, milderthan that observed in other reported cases of CMT1B, whichcan be misdiagnosed as the axonal form CMT2 and resem-bles the phenotype of the P0-deficient heterozygous mice.In another family with autosomal dominant CMT1, therewas a striking association with bilateral trigeminal neuralgiain several family members. Screening for gene mutationsrevealed a heterozygous missense mutation in the P0 gene.We fully evaluated a family in which a 66-year-old man andhis 32-year-old daughter had a severe early-onset demyeli-nating neuropathy. The father, chairbound since age 55, alsohad cranial nerve involvement (oculomotor paresis withdiplopia, sensorineural hearing loss, and vocal cord paresisrequiring tracheostomy). Sural nerve biopsy in the daughterdemonstrated severe loss of myelinated fibers with severalcomplex onion bulb formations. Both patients carried a het-erozygous missense mutation (Arg381His) in the gene cod-ing for Early Growth Response 2 (EGR2), a Schwann celltranscription factor that is thought to regulate myelinogene-sis and cranial nerve development.

Supported by Telethon grants to A.S. and F.T.

PATHOGENESIS OF CONGENITAL HYPOMYELINATION REVEALED BY P0 OVEREXPRESSING MICE

Previtali S., Quattrini A., Imperiale D.1, Canal N., TrappB.2, Messing A.3, Feltri M.L., Wrabetz L. S. Raffaele Scien-tific Institute, Dept. of Neurology and Dibit, Milan, Italy;1University of Turin, Italy; 2Cleveland Clinic Foundation,Cleveland, OH; 3University of Wisconsin, Madison, WI.

Extra copies of the myelin protein zero (Mpz) gene causedysmyelinating neuropathy in transgenic mice. Clinical andpathological findings are dose dependent, ranging from tran-sient perinatal hypomyelination (30% mRNA overexpression), toarrested nerve development with impaired sorting of axons bySchwann cells (700% mRNA overexpression). Mpz overexpres-sion promotes inappropriate trafficking of P0 protein to surfacemembranes of promyelinating Schwann cells. Ultrastructuralimmunocytochemistry demonstrates that mistargeting of P0 tothe membranes of the advancing mesaxon (the lip of Schwanncell membrane that enwraps the axon) activates P0 homophilicadhesion, arresting spiral wrapping and myelination.

Severely reduced nerve conduction velocities, paucityof active myelin destruction or onion bulbs, and redundantbasement membrane formation in P0-overexpressor miceresemble those present in human congenital hypomyelina-tion (CHN). CHN is a subtype of demyelinating neuropathydue to MPZ mutation. Although increased MPZ has not yetbeen described in CHN, increased myelin gene dosage(PMP22 and PLP) can cause hereditary myelinopathy in bothrodent and human (Charcot-Marie-Tooth IA and PelitzausMerzbacher disease). Of note, mutations in the Krox 20 tran-scription factor, encoded by EGR2, are also associated withCHN. Since one of these EGR2 mutations likely disinhibitsKrox 20, and Krox 20 may regulate P0 expression, it is possi-ble that MPZ overexpression contributes to the pathogene-sis of this EGR2 mutation.

PERIPHERAL NEUROPATHIES AND CHRONIC HEPATITIS CPrimavera A., Cocito L., Reni L., Caponnetto C., Abbruz-zese M. Deparment of Neurological Sciences, University ofGenova, Italy.

Objectives: Recent interest has been expressed inperipheral neuropathies in hepatitis C virus (HCV) patients.The aim of this prospective study was to evaluate the preva-lence of peripheral neuropathies associated with chronichepatitis and their clinical manifestations.

Patients and method: Ninety anti-HCV-positive patientswere consecutively interviewed and examined by the sameoperator. Forty-five patients with end-stage liver disease andawaiting liver transplantation were evaluated at the LiverTransplantation Center (Group 1). Further 45 patients werereferred for neurological consultation during hospitalisationin the Department of Medicine (Group 2), where they hadbeen admitted for different clinical reasons. One patientfrom group 1 and 5 patients from group 2 were excludedfrom the study because of previous neurological diseases.All patients underwent a standardized neurological evalua-tion, including history, neurological examination, mini mentalstate examination, neuropathy symptom score, and neuro-logical disability score. In presence of symptoms and signsof peripheral neuropathy, an electrophysiological evaluationwas performed.

Results: Signs or history of encephalopathy were foundin 23/44 patients of group 1 (52.2%) and in 8/40 patients ofgroup 2 (20%). Clinical manifestations of neuropathy, con-firmed by electrophysiological examination, were found in 11subjects of group 1 (25%) and in 17 patients of group 2(42.5%). Most patients had minor symptoms; sensory dis-turbances occurred more frequently than motor and auto-nomic dysfunctions. In group 1, peripheral neuropathy wasassociated with systemic illness (diabetes, renal failure, liverneoplasm, previous alcohol abuse) in 4/11 patients (36.3%);conversely, in all patients from group 2, other possible etio-logical factors were present: alcohol abuse in 3; diabetes in4; renal failure in 1; mixed cryoglobulinemia in 7; and neo-plasm in 2.

Conclusions: Symptomatic but not disabling neuropa-thies were found in 33% of HCV in patients. Sensoryinvolvement was prevalent. Systemic illness and mixed cryo-globulinemia were more frequently present in Group 2 thanin Group 1. This finding suggests that the metabolic dysfunc-tions caused by liver disease may be the primary determi-nant of peripheral system damage only in patients with end-stage liver disease.

MEISSNER CORPUSCLES IN PATIENTS WITH CONGENITAL AND ACQUIRED SENSORY NEUROPATHIESProvitera V., Nolano M., Crisci C., Stancanelli A., Balbi P.,Lullo F., Filla A.1, Santoro L.1, Caruso G.1 “Salvatore Maugeri”Foundation – Medical Centre of Telese T. (BN) Italy. 1 Dept. ofNeurological Sciences, University of Naples “Federico II.”

Cutaneous innervation and particularly Meissner Cor-puscles have been studied in glabrous skin of subjects withcongenital and acquired sensory neuropathies.

We performed 3-mm punch skin biopsies from finger-


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tips of 14 patients with Friedreich’s Ataxia (FA), 6 young sub-jects with diabetes mellitus without symptoms and clinicalor electrophysiological signs of sensory neuropathy, and in 4subjects with acquired sensory neuropathy of undefined ori-gin. An age- and sex-matched control group of ten healthysubjects underwent the same procedures. All subjectsincluded in the study signed an informed consent form.

Once fixed and cryoprotected, the skin specimens werecut in 100-micron-thick sections and immunostained usingprimary antibodies specific for collagen (Col IV), nerve fibers(PGP 9.5), myelin sheet (MBP), and Meissner corpuscle cap-sula (S100), and linked to secondary antibodies labeled withCy3 and Cy5 fluorophores. Digitized, completely in-focus 3Dimages were obtained from z-series of 2-mm-thick opticalsections acquired with a confocal microscope.

We found a reduction of Meissner corpuscle total num-ber, area, and density of innervation that appeared marked inpatients with FA and moderate in diabetic patients. The thirdgroup of patients showed anomalies ranging from a mildreduction of the Meissner corpuscle area and density ofinnervation to a complete loss of the receptors.

Punch biopsy turned out to be an accurate tool to studythe cutaneous innervation in glabrous skin and to assess thenervous structures health status also in the very early stagesof the sensory neuropathies.

PARANEOPLASTIC PERIPHERAL NEUROPATHYQuattrini A. San Raffaele Scientific Institute, Dept. of Neu-rology, Milano.

Paraneoplastic neurologic disorders are rare diseasesthat occur as a remote effect of cancer. Paraneoplastic syn-drome may affect any portion of the nervous system, caus-ing either diffuse or focal neurologic dysfunction. However,peripheral neuropathy is one of the most frequently encoun-tered. Subacute sensory neuropathy, which usually occurs inpatients with a previously undiscovered small-cell lung carci-noma (SCLC), is believed to result from an immune reactionagainst a protein antigen(s) expressed jointly by neurons andtumor cells. Anti-Hu antibodies are highly-specific diagnosticmarkers for paraneoplastic sensory neuropathy/encephalo-myelitis, which is nearly always associated with SCLC. Strongevidence suggests a pathogenic role for anti-Hu antibodies.

Peripheral nerve disorders also occur with lymphomaand plasma cell dyscrasia. I shall briefly review the neuropa-thies observed in association with malignant dyscrasia, suchas multiple myeloma, plasmacytoma, lymphoproliferativediseases, and amyloidosis.

Finally, peripheral neuropathy is an important and poten-tially dose-limiting complication of the new chemotherapeu-tic agents, which are often used in treating solid tumors.

CONGENITAL HYPOMYELINATION NEUROPATHY WITHA NOVEL MUTATION OF PMP22Rigatelli F., Fabrizi G.M., Simonati A., Cavallaro T., Fer-rarini M., Taioli F., Mostacciuolo M.L., Rizzuto N. Depart-ment of Neurological and Visual Sciences, Section of ClinicalNeurology, University of Verona. Verona.

Congenital hypomyelination neuropathy (CHN) has beenrelated with mutations of the MPZ gene that codes for P0,the major structural protein of the peripheral myelin and ofEGR2/Krox20 gene that codes for a transcription factoressential for the normal development of myelinating Schwanncell. More recently, we reported the association betweenCHN and a Ser72Leu mutation of the peripheral myelin pro-tein 22 (PMP22), a quantitatively minor component of thecompact myelin of peripheral nerves, whose functions arestill debated. Here we describe a second patient with CHNassociated with a novel mutation of PMP22.

The patient is the 4-year-old daughter of healthy non-consanguineous parents and is affected with early delay ofmotor development. At seven years she could not walk with-out support; examination disclosed muscle weakness andatrophy, foot drop, pes cavus, scoliosis, areflexia, and impair-ment of all sensory modalities. MNCV at the median nervewas 3.6 m/s. Nerve biopsy disclosed marked loss of fibers;residual fibers were devoid of myelin or encircled byextremely thin myelin sheaths and were surrounded bybasal laminae onion bulbs. Clinical follow up demonstratedno progression of the disease. Molecular analysis discloseda novel heterozygous T-to-C transition at nucleotide 374 ofPMP22, that is predicted to cause a nonconservative substi-tution of cysteine109 (a phylogenetically conserved residue)with arginine, in the third transmembrane domain.

The duplication of PMP22 causes the common demyeli-nating form of Charcot-Marie-Tooth neuropathy type 1 (CMT1).Our reports indicate that missense mutations of the sameprotein may cause dysmyelination rather than demyelina-tion, and prompt to investigate the function of PMP22 inmyelinogenesis as well as in Schwann cell differentiation.

PURE MOTOR CIDP. A DISTINCT ENTITY?Sabatelli M., Madia F., De Armas L., Tonali P. Istituto di Neu-rologia, Università Cattolica del Sacro Cuore, Rome.

The spectrum of clinical, pathological, and electrophysi-ological features of CIDP is very heterogeneous. The onsetmay be acute or slowly progressive and clinical coursemonophasic or relapsing-remitting. Motor-sensory, ataxicsensory and pure motor variants have been described. Theimportance of the classification of CIDP is not an academicone, as each subtype might respond to specific treatments.

We describe clinical features and long term follow up of4 patients affected by pure motor CIDP. 4 out of our 30 CIDPpatients showed no clinical, electrophysiological, or (in threepatients) sural nerve biopsy features of sensory fiber involve-ment. All four patients disclosed similar clinical, electrophys-iological features: the age of onset was before 30 years,clinical course was relapsing-remitting, and electrophysiolog-ical examination showed features of pure demyelinatingneuropathy with normal distal CMAP amplitude and clearevidence of conduction blocks. None of them showed signif-icant response to corticosteroids, while high-dose intrave-nous immunoglobulins were very effective in all patients.Three patients showed marked improvement with interferonalpha therapy. Two patients showed marked myastenic-likefluctuation of weakness


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Our findings suggest that pure motor CIDP representsa distinct entity. Supported by Telethon Italy.

PERIPHERAL NEUROPATHY IN HEPATITIS C VIRUS INFECTED PATIENTS WITH AND WITHOUT MIXED CRYOGLOBULINEMIA

Sampaolo S., Ambrosone L.1, Franzese G., De Martino L.,Panella G., Migliaresi S.1, Di Iorio G. Institute of Neurolog-ical Sciences and 1 Institute of Clinical Medicine - Rheuma-thology, Second University of Naples, Italy.

Objective: To evaluate immunohistochemical and ultra-structural changes in sural nerve biopsies from patients withperipheral neuropathy and hepatitis C virus (HCV) infection.

Methods: Frozen and plastic-embedded nerve specimenswere obtained from 19 HCV-positive patients with (16) or with-out (3) mixed cryoglobulinemia (MC). Immunoperoxidase andimmunofluorescence studies were performed on cryostatcross-sections using antibodies recognising cellular subsets andhumoral factors involved in the inflammation (CD68, CD11a-b-c,CD20, CD3, CD4, CD45, C1q, C3d, TCC, IgG, IgA, IgM). Semiand ultrathin sections were studied by standard protocols.

Results: Nerve biopsy showed an axonal degenerationwith microangiopathy (perineurial . endoneurial). IgM andIgG were observed as a thin sub-perineurial band and in thewall of endo and perineurial vessels in MC patients only.Immunoglobulin deposition colocalised in some nerves withcomplement factors. Macrophages and T memory/activatedlymphocytes were seen perivascularly and in endoneuriumwhile rare B-cells were detected in perineurium. In the MC-negative patients, the peripheral neuropathy was character-ised by a prominent myelin degeneration. The pattern of dis-tribution of immunoreactivity for humoral and cellular factorswas similar but not identical to that of MC patients.

Conclusions: Axonal degeneration characterises the HCV-related MC neuropathy and is likely secondary to ischaemia.The vascular damage is prevailing in perineurium and appearsto be mediated by both T-cells and immune complex. Myelinalterations mainly occur in MC-negative patients. These lastfindings suggest a primary pathogenetic role for HCV in theinduction of the nerve damage.

PERIPHERAL NEUROPATHY IN HCV-RELATED MIXED CRYOGLOBULINEMIA

Sanges G., Ammendola A., Ambrosone L.1, Sampaolo S.,Cesarano M., Migliaresi S.1, Di Iorio G. Institute of Neuro-logical Sciences and 1 Institute of Clinical Medicine - Rheu-mathology - Second University of Naples - Italy.

Objective: To evaluate the prevalence and features ofperipheral neuropathy in HCV-related mixed cryoglobuline-mia (MC).

Methods: 133 consecutive patients (23 males and 110females, age range 23–73 years) with MC (double immuno-diffusion) were studied. Immuno-fixation electrophoresiswas performed in 127 cases: in 117 a type II, and in 10 typeIII MC was found. In all the patients circulating anti-HCV anti-bodies and in 79/87 HCV-RNA were detected. ENG was per-formed in 52 patients and sural nerve biopsy in 16.

Results: Neurological examination revealed a peripheralneuropathy in 107 patients (80.4%): 50 had a distal symmet-ric sensory-motor polyneuropathy, 55 multiple mononeurop-athies, 2 a mononeuropathy. During the course of the illness,mononeuropathies tend to overlap giving a polyneuropathy.ENG showed neuropathic features in 48/52 patients (92.3%),8 of them without clinical symptoms of peripheral neuropa-thy. Axonal damage, mainly sensitive, more expressed in thelower limbs, was the commonest electroneurographic find-ing. Sural nerve biopsy showed axonal degeneration withperineurial and endoneurial microangiopathy, rare cellularinfiltrates, erytrocyte diapedesis.

Conclusions: Peripheral neuropathy is a common, early,and often severe complication in HCV-related MC. The pat-tern of nerve changes suggests a vascular mediated dam-age. Hypoxia and immunological factors may be concurrentpathogenetic mechanisms.

CHARCOT-MARIE-TOOTH WITH DIAPHRAGM AND VOCAL CORD PARALYSIS (CMT2C)

Santoro L.1, Manganelli F.1, Barbieri F.1, Di Maio L.1,Casari G.2 1Department of Neurological Sciences, Universityof Naples “Federico II.” 2S. Raffaele Scientific Institute, Dept.of Neurology, Milano.

Charcot-Marie-Tooth disease (CMT) is the most commoninherited disorder of the peripheral nervous system and isclinically and genetically heterogeneous. Recent advances ofmolecular genetics has dramatically increased our under-standing of the underlying disease mechanisms. Genetic link-age studies have identified a lot of genetic loci for differenttypes of inherited neuropathies, although most genesinvolved still remain to be found. In fact, the axonal type ofCMT associated with diaphragm and vocal cord paralysis(CMT2C) is not yet associated to a gene locus. We describeseven members affected by CMT2C belonging to a familyexpanded for three generations, and with a male-to-maletransmission. Four patients, all affected by vocal cord paraly-sis (VCp) showed also distal weakness and atrophy moreseverely in the lower limbs. Three of these patients weretreated surgically by arytenoidopexy for VCp, the last one withVCp and diaphragm paralysis was treated with cordectomy.

Three other patients showed marked weakness andhypotrophy of upper and lower limbs. Two of these patientscomplained of laryngeal stridor and dispnoea during activity,the last one had neonatal diagnosis of SMA, but did notshow respiratory impairment. All patients had pes cavus andabsence of deep tendon reflexes. EMG examination showedclear neurogenic lesions in all the patients and in all theexplored muscles. Conduction velocity (CV) studies showedan almost normal CV, while sensory- and motor-evokedpotentials had a severe amplitude reduction. Sural nervebiopsy performed in one patient showed clear signs of axonaldegeneration.

Our data confirm the association between VCp andaxonal type of CMT, already described in isolated cases butonly in two families in literature. We are trying to perform alinkage analysis in this family and we hope that this can helpin understanding pathophysiologic mechanisms and theassociation between VCp and CMT.


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SCHWANN CELL APOPTOSIS IN TISSUE CULTURE FOLLOWING THE ADMINISTRATION OF PRO-INFLAMMATORY CYTOKINESScarpini E., Conti G., Bava L., Bussini S., Baron P., De PolA.1, Vaccina F.1, Scarlato G. Dept. of Neurology, “Dino Fer-rari” Center, University of Milan. 1 Dept. of MorphologicalSciences, University of Modena.

In immune-mediated demyelination of the nervous sys-tem, glial cell apoptosis has been observed recently; however,the relevance of the phenomenon and the characterization ofthe involved molecules are still controversial. Cytokines aresecreted by many cells, including inflammatory and glial cells,and appear to play a relevant role in the peripheral nervoussystem (PNS) immuno-mediated demyelination, being activein promoting the damage to Schwann cells, myelin, andaxons. Even though the exact role of the different cytokines isat present uncertain, they have a sequential different expres-sion in PNS immune-mediated demyelination and couldinduce apoptotic death of Schwann cells in the vicinity of theinflammatory reaction via the expression of CD95 (Apo1/Fas).This study has been designed to detect in rat primarySchwann cell tissue cultures whether the administration ofIL-1B and IFN-y can induce cell death. Identification of apop-totic Schwann cell was performed by morphological, immuno-histochemical, and electron-microscopy analysis. Our resultsshow that Schwann cells stimulated by proinflammatorycytokines IL-1B and IFN-y show morphological evidence ofnuclear chromatin condesation at the DAPI staining and areTUNEL positive. The same features of apoptotic cell deathwere observed by electron microscopy. These findings pro-vide evidence to support the hypothesis that cytokines candirectly damage Schwann cells in disorders of the PNS.

SENSORY GANGLIONOPATHY ASSOCIATEDWITH SJÖGREN’S SYNDROME PRESENTINGWITH DYSPHAGIAScoditti U., Palomba V., Marbini A., Pavesi G., GemignaniF. Istituto di Neurologia, Università di Parma - Parma.

Sensory ganglionopathy is a sensory neuropathy char-acterized by inflammatory infiltration of the sensory ganglia,including trigeminal ganglia, in association with Sjögren’ssyndrome, or idiopathic. We report a patient who had apeculiar presentation with dysphagia.

A 76-year-old man presented with a 1-year history ofdysphagia and weight loss, and facial dysesthesias. A diag-nosis of amyotrophic lateral sclerosis was initially suspected,because of muscular atrophy and bulbar signs, however EMGshowed only mild neurogenic changes, excluding signs ofmotor neuron involvement.

Neurological examination showed absent corneal reflexes,moderate muscular wasting and mild weakness in the extrem-ities, absent deep tendon reflexes in the legs, and sensoryloss over the face and extremities.

Electroneurographic study demonstrated absent blinkreflex, and severely decreased or absent sensory actionpotentials in the limb nerves.

Laboratory investigations, including CSF examinationand search for anti-neural antibodies, were negative.

A sicca syndrome was demonstrated by Schirmer test andsalivary gland scintigraphy, and lower lip biopsy showed focalsialoadenitis according to the criteria of Greenspan et al (1974).

A pure sensory or mainly sensory neuropathy with prom-inent trigeminal involvement is quite typical in the course ofcollagen diseases, and in particular in Sjögren’s syndrome,supported by T cell infiltration in the dorsal root ganglia. In ourcase, the presence of sicca syndrome and focal sialoadenitiswas consistent with the diagnosis of Sjögren’s syndrome. Wesuggest that dysphagia, an atypical symptom in sensory gan-glionopathy, may be related to involvement of the sensoryganglia of the glossopharyngeal and/or vagus nerve.

CLINICAL, MRI, AND SKIN BIOPSY FINDINGS IN SENSORY GANGLIONOPATHIES

Sghirlanzoni A., Pareyson D., Grisoli M.1, Lombardi R.,Lauria G. Departments of Neurology and 1Neuroradiology,National Neurological Institute “C.Besta”, Milan, Italy.

Unlike peripheral motor disorders, sensory disturbancesare rarely diagnosed by the probable site of pathology. Thisapproach is useful in the differential diagnosis betweenchronic sensory axonal neuropathies and ganglionopathies,in which routine clinical and neurophysiological evaluationalone often do not provide definite clues.

Methods: Thirty patients with peripheral sensory distur-bances were investigated. MRI was performed at cervicallevel in all cases. Four patients also underwent thoracic andlumbar MRI. Seventeen patients underwent skin biopsy atthe proximal thigh and the distal leg. In 4 of them, furtherskin biopsies were taken at C5 dermatome and at the hand.Density of intra-epidermal nerve fibers (IENF) was quantified.

Results: In 22 patients, sensory ganglionopathy wassuspected. Disease was idiopathic in 7 cases; paraneoplas-tic in 3 cases; and associated with Sjögren, AIDS, autoim-mune chronic hepatitis, and cisplatin neurotoxicity in 4 cases.One patient had a hereditary sensory autonomic neuropa-thy. Four patients had vitamin E deficiency and 3 patients aspinocerebellar syndrome. In 8 patients, sensory axonalneuropathy related to diabetes, alcoholism, and AIDS onantiretroviral treatment, and monoclonal gammopathy ofundetermined significance was diagnosed.

MRI findings: All ganglionopathy patients showed pos-terior columns hyperintensity on T2-weighted MRI. Conversely,MRI was negative in all axonal sensory neuropathy patients.

Skin biopsy findings: In neuropathies, IENF density wassignificantly lower at the distal leg than at the proximal thigh,while ganglionopathies did not show any change withrespect to the rostral:caudal orientation. A similar pattern ofepidermal denervation was observed in the arm.

Discussion: The degeneration of both central and periph-eral sensory pathway in a fashion that is not length-depen-dent localizes the disease to T-shaped sensory neurons Earlyataxia and cutaneous sensory symptoms involving the proxi-mal regions of the body reflect this pattern of denervationand should prompt the diagnosis of ganglionopathy. This canbe confirmed by T2-weighted hyperintensity in the posteriorcolumns and a distinct pattern of IENF loss.


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A NOVEL MUTATION OF CONNEXIN-32 GENE IN A CMTX ITALIAN FAMILYSiciliano G., D’Avino C., Pellegrinetti A., Rocchi A., Sar-tucci F., Mostacciolo M.L.1 Dept. of Neuroscience, Univer-sity of Pisa. 1Dept. of Biology, University of Padova.

X-linked Charcot-Marie-Tooth is an inherited motor andsensory neuropathy associated with mutations in GJB1, agene on chromosome X coding for the gap junction protein“connexin 32” (Cx32). Cx 32 gene is expressed in bothperipheral and central nervous system myelin.

We describe a family affected by X-linked CMT neuropa-thy with a novel point mutation in Cx32 gene, in which themother, the putative carrier, and three affected sons wereexamined. The affected sons (32, 35, 38 yrs) presented amotor-sensory slowly progressive neuropathy mainly involv-ing lower limbs. Nerve conduction study showed bothaxonal and demyelinating pattern of denervation. Evokedpotentials indicated visual and brainstem auditory pathwayinvolvement. The mother showed subclinical electrophysio-logical abnormalities in nerve conduction velocities.

By mutational analysis of GJB1 using SSCP and sequenc-ing of candidate regions, a previously undescribed missensemutation in the exon 2, codon 151, was found. This mutationwas due to a transversion (TAT-. TCT) leading to a Tyr-.Sersubstitution in the 2nd extracellular domain.

Our findings further stress the wide variability in thespectrum of Cx32 mutations associated to CMTX, making itworthwhile to deepen knowledge about genotypic–pheno-typic interrelationship in this disease.

TRANSFECTION OF PRIMARY SCHWANN CELL CULTURES AND OF ORGANOTYPIC DORSAL ROOT GANGLIA CULTURES: PRELIMINARY RESULTS AND TECHNICAL CONSIDERATIONS

Zerega B.1, Nobbio L.1, Paleari L.2, Levi G.2, AbbruzzeseM.1, Torre G.C.3, Banchi L.1, Mancardi G.L.1, andSchenone A.1. 1 Department of Neurological Sciences and

Vision, University of Genova. 2 Advanced Biotechnology Cen-ter CBA-IST, Genova. 3 Department of Endocrinological Sur-gery, University of Genova.

The most common forms of Charcot-Marie-Tooth (CMT)disease are due to duplication/deletion of the myelin protein 22gene (PMP22); however, several patients harbor point muta-tions in PMP22 or in other myelin related proteins. To study themechanism by which dominant point mutations affect myelinformation and maintenance, we are attempting to optimizegene transfer protocols into Schwann cells (SC) that will intro-duce expression constructs carrying mutated cDNA.

Initial experiments were carried out on pure primary cul-tures of SC from sciatic nerves of newborn rats, co-culturedwith primary sensory neurons under conditions inducingmyelination in vitro. Using the EGFP expression vector,which induces endogenous green fluorescence in the trans-fected cells, we have tested a number of gene transferapproaches, including electroporation and polycationic reagents(FuGene). Best results are obtained with the FuGene reagent(Boheringer) (up to 25%), while the electroporation is lessefficient (5%–12%). However, the difficulties in selectingand expanding SC after transfection need to be overcome.Thus, we are optimizing gene transfer procedures on organ-otypic cultures of dorsal root ganglia from 15 day-old-ratembryos. SC and neurons are identified by their morphol-ogy; immunostaining with S100 and antibodies to phosphor-lated neurophylaments are used to recognize, respectively,SC and axons. Using either Lipofectamine 2000 (GIBCO)and FuGene, polycationic reagents, SC are trasfected to lev-els of efficiency comparable or better than pure culture pro-tocols. The same cultures maintained for 15 days aftertransfection showed extensive axonal growth and initialmyelin formation. Scattered SC were still expressing thetransgene at a visible level.

These advances will likely help in understanding therole of specific genes in myelination and learning howtheir mutated forms lead to hereditary demyelinating neuro-pathies.

electroneurography in guillain-barre, syndrome (gbs): sensitivity and specificity

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