hsv encephalitis
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HSV Encephalitis. Jack Kuritzky, PGY-2 UNC Internal Medicine August 31, 2009. HSV Encephalitis: General. Encephalitis: 20,000 cases/year HSV accounts for 10-20% HSV-1 causes encephalitis in adults HSV-1 or HSV-2 in neonates HSV-1 and 2 associated w/Mollaret’s meningitis - PowerPoint PPT PresentationTRANSCRIPT
HSV EncephalitisHSV EncephalitisJack Kuritzky, PGY-2Jack Kuritzky, PGY-2
UNC Internal MedicineUNC Internal Medicine
August 31, 2009August 31, 2009
HSV Encephalitis: HSV Encephalitis: GeneralGeneral
Encephalitis: 20,000 cases/yearEncephalitis: 20,000 cases/year HSV accounts for 10-20%HSV accounts for 10-20%
HSV-1 causes encephalitis in adultsHSV-1 causes encephalitis in adults HSV-1 or HSV-2 in neonatesHSV-1 or HSV-2 in neonates HSV-1 and 2 associated w/Mollaret’s meningitisHSV-1 and 2 associated w/Mollaret’s meningitis
Benign recurrent lymphocytic meningitisBenign recurrent lymphocytic meningitis
Preferentially affects temporal lobePreferentially affects temporal lobe Can rarely cause recurrent brainstem Can rarely cause recurrent brainstem
encephalitisencephalitis HSV-2 tends to cause global encephalitisHSV-2 tends to cause global encephalitis
1/3 cases <20yrs and 1/2 cases >50 yrs1/3 cases <20yrs and 1/2 cases >50 yrs
HSV Encephalitis: HSV Encephalitis: PathogenesisPathogenesis
Infiltrates CNS via 3 routesInfiltrates CNS via 3 routes 1. Trigeminal nerve or olfactory tract1. Trigeminal nerve or olfactory tract
Typically after primary infectionTypically after primary infection <18yrs old<18yrs old
2. CNS invasion after recurrent infection2. CNS invasion after recurrent infection Viral reactivation w/subsequent spreadViral reactivation w/subsequent spread
3. CNS infection w/o primary or recurrent HSV-13. CNS infection w/o primary or recurrent HSV-1 Latent HSV in situ within CNSLatent HSV in situ within CNS
Invades and replicates in neurons and gliaInvades and replicates in neurons and glia Causes necrotizing encephalitisCauses necrotizing encephalitis Widespread hemorrhagic necrosis throughout Widespread hemorrhagic necrosis throughout
parenchymaparenchyma
HSV Encephalitis: HSV Encephalitis: PathogenesisPathogenesis
Necrosis of temporal lobeNecrosis of temporal lobe
HSV Encephalitis: HSV Encephalitis: PathogenesisPathogenesis
Necrosis of temporal lobeNecrosis of temporal lobe Immune mediatedImmune mediated
Not more common in immunosuppressedNot more common in immunosuppressed Small studies suggest HSV viral load does Small studies suggest HSV viral load does
not correlate with degree of temporal lobe not correlate with degree of temporal lobe damagedamage
HSV Encephalitis: HSV Encephalitis: PresentationPresentation
FeverFever Altered mental status Altered mental status Altered level of consciousnessAltered level of consciousness Focal cranial nerve deficitsFocal cranial nerve deficits HemiparesisHemiparesis Dysphasia/aphasiaDysphasia/aphasia AtaxiaAtaxia Focal seizures Focal seizures
HSV Encephalitis: HSV Encephalitis: PresentationPresentation
FeverFever Altered mental statusAltered mental status Altered level of consciousnessAltered level of consciousness Focal cranial nerve deficitsFocal cranial nerve deficits HemiparesisHemiparesis Dysphasia/aphasiaDysphasia/aphasia AtaxiaAtaxia Focal seizuresFocal seizures
HSV Encephalitis: HSV Encephalitis: PresentationPresentation
More on AMS – consequences of More on AMS – consequences of temporal lobe damagetemporal lobe damage Hypomania - elevated mood, excessive Hypomania - elevated mood, excessive
animation, decreased need for sleep, animation, decreased need for sleep, inflated self-esteem, and hypersexuality inflated self-esteem, and hypersexuality
Kluver-Bucy syndrome (KBS)Kluver-Bucy syndrome (KBS) Initially seen in Rhesus monkeysInitially seen in Rhesus monkeys Loss of normal anger and fear responses Loss of normal anger and fear responses Increased sexual activityIncreased sexual activity AmnesiaAmnesia
HSV Encephalitis: HSV Encephalitis: DiagnosisDiagnosis
CSFCSF Lymphocytic pleocytosisLymphocytic pleocytosis Erythrocytosis (84% of patients)Erythrocytosis (84% of patients) Elevated proteinElevated protein
Low glucose uncommonLow glucose uncommon CSF PCR now diagnostic test of CSF PCR now diagnostic test of
choicechoice Quickest, sensitive, and specificQuickest, sensitive, and specific HSV culture out of favorHSV culture out of favor Brain biopsies previously performedBrain biopsies previously performed
HSV Encephalitis: HSV Encephalitis: DiagnosisDiagnosis
Imaging Imaging Temporal lobe Temporal lobe
injuryinjury
HSV Encephalitis: HSV Encephalitis: DiagnosisDiagnosis
Imaging – Temporal lobe injuryImaging – Temporal lobe injury Usually unilateralUsually unilateral May have mass effectMay have mass effect MRI much more sensitive/specificMRI much more sensitive/specific
EEG – focal findings in >80% casesEEG – focal findings in >80% cases High amplitude slow waves (delta and theta High amplitude slow waves (delta and theta
slowing)slowing) Continuous periodic lateralized Continuous periodic lateralized
epileptiform discharges in the affected epileptiform discharges in the affected region region
HSV Encephalitis: HSV Encephalitis: TreatmentTreatment
EARLY TREATMENT IMPERATIVE!EARLY TREATMENT IMPERATIVE! Before loss of consciousness Before loss of consciousness Within 24 hours of the onset of symptoms Within 24 hours of the onset of symptoms Glasgow Coma Scale score of 9 to 15Glasgow Coma Scale score of 9 to 15
Acyclovir 10 mg/kg IV Q 8h (infuse slowly Acyclovir 10 mg/kg IV Q 8h (infuse slowly to prevent crystalluria/renal failure)to prevent crystalluria/renal failure) Mortality 19-28% vs. 50-58% w/vidarabineMortality 19-28% vs. 50-58% w/vidarabine 6 month functional status significantly better 6 month functional status significantly better
w/acyclovirw/acyclovir Treat 14-21 daysTreat 14-21 days
Future treatment Future treatment steroids? (non- steroids? (non-randomized, retrospective study)randomized, retrospective study)
HSV Encephalitis: HSV Encephalitis: PrognosisPrognosis
Untreated, mortality 70%Untreated, mortality 70% Survivors with severe neurologic damageSurvivors with severe neurologic damage
With treatment—mortality ~20%!With treatment—mortality ~20%! Severe disability in 20%Severe disability in 20%
Simplified Acute Physiology Score II >/=27Simplified Acute Physiology Score II >/=27 Delay >2 days b/w admission and acyclovirDelay >2 days b/w admission and acyclovir GCS <6GCS <6 Age>30Age>30
62% of survivors have neurologic sequelae62% of survivors have neurologic sequelae
REFERENCESREFERENCES
Kimberline, DW. Management of HSV Encephalitis in Adults Kimberline, DW. Management of HSV Encephalitis in Adults and Neonates: Diagnosis, Prognosis, and treatment. and Neonates: Diagnosis, Prognosis, and treatment. Herpes. (14)1. 2007.Herpes. (14)1. 2007.
Klein, R. “Clinical manifestations and diagnosis of herpes Klein, R. “Clinical manifestations and diagnosis of herpes simplex virus type 1 infection”. UpToDate, version 17.2. simplex virus type 1 infection”. UpToDate, version 17.2. Jan 2009.Jan 2009.
Klein, R. “Herpes Simplex Type 1 Encephalitis”. UpToDate, Klein, R. “Herpes Simplex Type 1 Encephalitis”. UpToDate, version 17.2. Feb 2009.version 17.2. Feb 2009.
Shandera, WX and H Koo. “Infectious Diseases: Viral & Shandera, WX and H Koo. “Infectious Diseases: Viral & Rickettsial”. Rickettsial”. 2007 Current Medical Diagnosis & Treatment2007 Current Medical Diagnosis & Treatment. . 4646thth ed. The McGraw Hill Companies: USA. 2007. ed. The McGraw Hill Companies: USA. 2007.
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