SEIZURES IN CHILDREN

Rashmi Kumar

Prof & Head, Pediatrics

King George Medical University

Lucknow

• Prevalence • Definition• Conditions that mimic seizures• Pathophysiology• Etiology• Age wise etiology• Classification• Assessment• Febrile seizures• Management

SEIZURES

• One of the most common life threatening events in childhood, more than adults

• Paroxysmal electrical activity in brain --> motor/sensory/autonomic disturbance with /without alteration of consciousness

• Convulsion – seizure with motor activity 5%

• Epilepsy – recurrent (2 or more) unprovoked seizures beyond newborn period 0.5%

Seizures: DDxTremors –distal, rhythmic, equal amplitude, no loss of consciousnessJitteriness

Breath holding spells –always after crying, sequence of events important

Syncope – after prolonged standing/emotional upset, gradual loss of consciousness, slow pulse, pallor,

sweating, improves in supine/head down position

Pseudoseizures – older girl, never hurts herself, bizarre movements, normal s Prolactin

Detailed sequence of events necessary – HISTORY, HISTORY, HISTORY

Seizures: Pathophysiology:

Sustained partial depolarisation in a group of neurons -->excitability --> sudden depolarisation in response to stimuli -->conduction to surrounding cells, distant synaptically connected cells & subcortical neurons -->dissemination -->loss of consciousness

SEIZURES - ETIOLOGY1st fit/ recurrent fitsI Symptomatic• Infectious/ post infectious (including granulomas)• Anoxic/post anoxic• Vascular• Trauma/post traumatic• Tumour• Congenital - porencephaly, lissencephaly, agenesis of corpus callosum,

neurocutaneous syndromes• Degenerative• Metabolic - hypocalcemia/hypomagnesemia• hypo/hypernatremia• hypoglycemia• pyridoxine deficiency• Inborn errors • Drugs/Toxins -aminophylline,antihistamines,steroids,phenothiazines,• hexachlorophene, strychnine, camphor, INH, tetanus, lead, • shigella/salmonella• Acute cerebral edema - Hypertension• Febrile

II Idiopathic

Newborn 1-6 mths 6m-3 yrs >3 yrs

Birth asphyxia/trauma birth asphyxia Febrile idiopathicIVH cranial malformations CNS infectionsHypocal/hypoglyc inborn errors IU infections IU infections

DegenerativeMeningitis metabolicTetanus

tumour

Inborn errors other

KernicterusPolycythemiaNarcotic withdrawal

CLASSIFICATION OF EPILEPTIC SEIZURES: ILAE 1981

• I Partial 54%– Simple - motor/sensory/autonomic 7.7%– Complex 35.5%– Partial with secondary generalization 56.4%

• II Generalised 40.4%– Tonic clonic 69%– Absence 3%– Myoclonic 20.5%– Tonic 4.1%– Atonic 3.1%

• III Unclassifiable 6% (hospital based study in Mumbai)

• However, same patient can have more than 1 type• Many patients show a distinct evolution of disease

CLASSIFICATION OF EPILEPTIC SYNDROMES : ILAE 1989

I Localisation related• Symptomatic• Cryptogenic• IdiopathicII Generalised• Idiopathic• Cryptogenic

– West syndrome– Lennox Gastaut syndrome– epilepsy with myoclonic astatic seizures– epilepsy with myoclonic absences

• Symptomatic– Non specific– specific

III Epilepsies undetermined whether focal or generalisedIV Special syndromes

CLASSIFICATION OF EPILEPSY STILL EVOLVING

EPILEPSY - SPECIAL TYPES:

GTCS: v common• Aura tonic spasm loss of consciousness fall clonic

movements• Rolling of eyeballs/Frothing at mouth/Distortion of face• Incontinence/ Jerky breathing• Post ictal sleep

Absence epilepsy

• 2-4% of childhood idiopathic epilepsy• Girls 3-7 yrs, normal IQ• Transient loss of consciousness for few secs• No loss of tone • Ppted by hyperventilation -

• Treatment – Ethosuximide, valproate• May develop GTCS• EEG - 3/sec spike & wave activity

EPILEPSY - SPECIAL TYPES:

Infantile spasms: Onset in 1st year• Sudden flexion/extension in series esp on awakening• Upto 100 times /day• 60% secondary, 30% cryptogenic • Treatment - ACTH/steroids/ vigabatrin• Associated with mental regression• EEG - hypsarrhythmic• May develop GTCS

Lennox Gastaut: • 1-8 yrs, • tonic/atonic/absence type• EEG - diffuse 2 Hz spike-waves• Very difficult to control

EPILEPSY - SPECIAL TYPES:

Psychomotor (Temporal lobe) seizures: Complex partial seizures with origin in temporal lobe.

• Purposeful but inappropriate acts 'automatisms' • Associated with behavioral problems• Difficult to diagnose or treat.

Benign epilepsy with centrotemporal spikes: Partial, idiopathic, • orofacial/hemifacial, 3-13 yrs, often during sleep. Easy to

control

Myoclonic: heterogenous, multiple causes

Juvenile myoclonic: myoclonic jerks esp after awakening• EEG - 4-6 Hz polyspike, photosensitivity, GTCS may occur• Good response to Valproate

FEBRILE SEIZURES:

• 2-4% of children• 3m - 5 yr age• Assn with fever due to extracranial infection• Generalised, Short lasting, only one sz per illness• No mental/neurological/EEG abnormality• Typical vs Atypical (complex)• Focal• Prolonged• >1 seizure during illness• 1/3 have at least 1 recurrence• 1/6 have multiple recurrences• Risk of epilepsy:

– Fh/o epilepsy– Atypical– Abnormal neurologic/mental status

Febrile Seizures: Management

• Exclude CNS infection• Control fever• Look for & treat cause of fever• Rectal diazepam• Explain to parents, reassure• If multiple - intermittent oral diazepam by

80%• If high risk for epilepsy long term

phenobarb/valproate.

Seizures: ASSESSMENTHistory:• 1st seizure/ recurrent seizures• Fever• Precipitating factors – diarrhea/ vomiting/ drug/ toxin/ metabolic• Headache/vomiting/visual loss• Duration• Age at onset• No of attacks• Frequency /, change in seizure type, last seizure when?• Exact description

– Aura– partial/generalised onset– Loss of consciousness– Tonic/clonic phase– Associated events - bed wetting/fall/tongue bite– Duration– Post ictal

• Precipitating factors• Diurnal• Family history• Antecedant events - trauma/CNS infection/asphyxia• Personality change/intellectual deterioration• Failure to thrive• Developmental milestones• Treatment

Seizures: ASSESSMENT

Examination:• BP• Head circumference• Skin lesions• Facial features• Organomegaly• Fundus• Meningeal signs• Neurological deficit• Development

Seizures: Investigations

• If features of CNS infection - CSF examination• Glucose, Ca, Mg - low yield• Skull Xray - calcification/ ICT - low yield• EEG: Always diagnostic during a seizure• Interictal record : normal in 40-50% of epileptics (spikes/sharp waves &

spikes –slow wave complexes) yield with sleep, sleep deprivation, hyperventilation, photic

stimulation• 2-10% normal population may have epileptic changes• EEG indicated in all cases of epilepsy for:• -confirmation of diagnosis & syndrome• -type of seizures - absence vs temporal lobe,• primary generalised vs secondarily generalised• -presence of underlying lesion/ idiopathic vs symptomatic• -follow up• -before withdrawal of AEDs• -localisation of focus before surgery• Video EEG

Seizures: Imaging - CT/MRI

Has revolutionised the management of epilepsyIndications: focal features on exam, EEG Features of ICT IntractableHowever, now indicated in every case with unknown causeNot necessary in febrile/absence/BETS/ JME etc.Western studies - 30% abnormal (30-50% of focal) -only 3% treatableIndian studies: Very high prevalence of granuloma like lesions –recent onset

partial seizures in child/young adult40% abn even after 1st seizure indicated in every case

MCQ

• The following are features of benign (typical) febrile seizures except:

• They are short lasting

• They are always generalised

• They only occur within 4 hours of fever onset

• They do not recur in the same febrile illness

The typical EEG pattern in absence epilepsy is:

• Intermittent spike and slow waves

• Hypsarrythmia

• Burst suppression

• 3 per second spike and waves

The following is true about absence epilepsy

• It occurs more commonly in boys

• There is loss of tone

• It is precipitated by hyperventilation

• Imaging is usually abnormal

Definition of epilepsy includes:

• At least 3 seizures

• EEG is abnormal

• Imaging is abnormal

• Beyond neonatal period

The following is true about breath holding spells:

• It is usually preceded by crying

• Child is always blue

• There is no loss of consciousness

• EEG may show spikes

The following is true about infantile spasms except:

• They occur in clusters

• They may appear like ‘startling’

• They usually occur during sleep

• They are also called ‘salaam attacks’

West syndrome usually has the following features except:

• Infantile spasms

• Onset in newborn period

• Hypsarrythmia on EEG

• Psychomotor retardation or regression

Imaging in seizures is not indicated in:

• Generalised tonic clonic seizures

• Absence seizures

• Temporal lobe seizures

• Infantile spasms

Prevention of febrile seizures can be achieved by:

• Intermittent phenobarb

• Long term phenytoin

• Intermittent diazepam

• Long term carbamazepine

Emergency dose of IV diazepam for seizure control is:

• 1 mg/kg

• 0.5 mg/kg

• 0.1 mg/kg

• 0.3 mg/kg

Seizures - Management

• I Management of acute attack:• Calm down• Head down lateral position• Prevent hurt• If does'nt stop convulsing in 3-5 min, • Inj Diazepam 0.3 mg/kg slow iv bolus • Maybe repeated after 20 min• Effect lasts 0.5-3 hrs• SE- hypotension, respiratory depression, secretions• or• Rectal diazepam 0.5 mg/kg dose/ nasal midzolam

0.2 mg/kg/dose

Domiciliary Mx

• Rectal Diazepam 0.5 mg/kg

• Intranasal midzolam 0.2 mg/kg

Seizures: Status epilepticus:

• Prolonged seizure for >20 min or repeated seizures without regaining consciousness

• Persistent seizure activity hypoxia, hypoglycemia, hyperthermia, cerebral edema & vasomotor instability

• Life threatening

• Risk of permanent brain damage Medical emergency

Mx of Status epilepticusICU, monitoringIV dextrose dripOxygen

IV Inj Diazepam 0.3 mg/kg or Lorazepam 0.1 mg/kg (longer action) or Midzolam (lesser respiratory depression)

Inj phenytoin 15-20 mg/kg iv at a rate of <1mk/kg/min

Inj Phenobarbitone 20 mg/kg iv at a rate of 1 mg/kg/min or IV Valproate 20 mg/kg as infusion in 50 ml NS over 30 min

Ventilatory support + diazepam/midzolam infusion `` Thiopental infusion

LONG TERM MANAGEMENT OF EPILEPSY:

I General advice:

• As normal a life style as possible

• No swimming/cycling on road/driving

• Inform teacher

• First aid

• Seizure dairy

• Regularity

LONG TERM MANAGEMENT OF EPILEPSY:

Drugs:

• When to start? If 2 or more seizures within a 12 month period

• Monotherapy:• Start at lower limit & build up gradually till toxicity/control• If no effect at maximum dose, taper off while introducing

2nd drug• 4 first line drugs - Carbamazepine, phenytoin, valproate

and phenobarbitone• No drug completely safe• 70% can be controlled

First line AEDs

Carbamazepine: • Ind: Partial, tonic clonic• Dose: 10-30 mg/kg/d in 2-3 doses13-18 hrs, • Adv: Relatively safe, improves cognitive fn.• SE: Diplopia,drowsiness, giddiness

initially.Hepatitis, skin rash, BM depression, drug interactions, dystonia, can aggravate minor motor seizures

First line AEDs

Sodium valproate: Ind: Broad spectrumDose: 20-30 mg/kg/d (upto 80) in 2-3 doses Half Life; 7-10 hrsSE: Nausea, vomiting, wt gain, hair loss,

hepatic failure, tremors, platelets, s ammonia, s carnitine, no correlation between drug levels & toxicity, levels of other AEDs

First line AEDs

Phenobarbitone

Ind: Tonic-clonic, partial, febrile

Dose: 3-6 mg/kg/d as single doses

level:10-15 g/ml20-80 hrs

Adv: Cheap, once daily dose

SE: Drowsiness, hyperkinesia, cognitive impairment ??, rash, rickets

First line AEDs

Diphenylhydantoin:Ind: Tonic-clonic, atonic, partiaDose: l4-8 mg/kg/d in 2 doseslevel: 10-20 g/mlHalf Life: Upto 20 hrsSE: Hirsutism, gum hyperplasia, rickets,

ataxia, lymphoma like syndrome, Sle like illness, megaloblastic anemia, rash, low margin of safety

Ethosuximide:Ind: Absence seizuresDose: 20-25 mg/kg/d in 2 dosesHalf Life: 4-30 hrsSE: Photophobia, WBC, nephrosis, blood

dyscrasiaACTH: Ind: West syndromeDose: 20-40 u/d for 4-6 wksSE: hypercortisolism

NitrazepamInd: Myoclonus, atypical absenceDose: 0.5 mg/kg/d in 2 dosesSE: Sleepiness, salivation,hypotonia, ataxia,

toleranceClonazepam

Dose: 0.05-0.25 mg/kg/d in 3 doses\

• Drug level monitoring• EEGs• When to stop ? 2-3 yrs seizure free

Newer AEDs

ClobazamInd: Partial, generalised & myoclonus (add on drug)

Dose: 0.5 mg/kg/d single dose

SE: Drowsiness, tolerance, secretions

GabapentinInd: Secondarily generalised, complex partial

SE: liver enzymes, impaired swallowing & aspiration, somnolence, fatigue, dizziness, wt gain

LamotrigineInd: Generalised, absence, JME, LG syndrome

SE: Synergy with valproate, skin rash, SJ syndrome

Newer AEDs/ Other modalitiesTopiramate:

Ind: Partial, generalised, drop attacks, LG syndrome

SE: ?cognitive impairment

Vigabatrine:Ind: Partial, infantile spasms

Dose: 40-80 mg/kg/d

SE: Drowsiness, agitation, confusion

Oxcarbazepine: Derivative of carbamazepine

• Ketogenic diet• Surgery