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Epilepsy is a condition characterized by recurrent (two or more) epileptic seizures, unprovoked by an immediate identified cause. Multiple seizures occurring in a 24 hours period are considered a single event.

Childhood seizures can be classified as

A. Generalized Seizures :

When clinical symptomatology provides no indication of an anatomic localization and there is no clinical evidence of focal onset, the seizure is a generalized seizure. There are 3 main sub types :

(a) Generalized convulsive seizures with predominantly atonic, tonic, clonic or tonic clonic features

(b) Absence seizure

(c) Myoclonic seizures

B.Partial Seizures :

When there is evidence of a clinical partial onset, regardless of whether the seizure is secondarily generalized. The first clinical signs of a seizure (the aura) have a highly localizing value and result from the functional neuronal activation of part of one hemisphere. Partial seizures can be classified as:

Simple partial seizure(SPS): When alertness and ability to interact appropriately with the environment is maintained, the seizure is classified as SPS.

Complex partial seizure (CPS): When there is impairment of consciousness, amnesia or confusion during or after a seizure the seizure is classified as CPS.

Partial seizure, secondarily generalized : When seizure becomes secondarily generalized the seizure is classified as partial seizure secondarily generalised.

Partial seizure of unknown type is said to occur when distinction between SPS and CPS cannot be made.

When a patient has several types of partial seizures, each should be separately categorised.

Partial seizure can arise from frontal lobes, parietal lobes or temporal lobes, occipital lobes or arising from multiple lobes or sometimes locus of onset remains unknown.

C. Febrile seizure :

It is an epileptic seizure occurring in childhood after age of one month, associated with a febrile illness not caused by an infection of the CNS, without previous neonatal seizures or a previous unprovoked seizure and not meeting criteria for other acute symptomatic seizures.

D. Neonatal seizure :

An epileptic seizure occurring in the first 4 weeks of life can be called neonatal seizures.

E. Non-epileptic events are :

Clinical manifestations presumed to be unrelated to an abnormal and excessive discharge of a set of neurons of the brain including

(a) disturbances in brain function (vertigo or dizziness, syncope, sleep and movement disorders, migraine, enuresis),

(b) pseudoseizures (non-epileptic, sudden behavioral episodes presumed to be of psychogenic origin, these may coexist with true epileptic seizure).

F. Epileptic syndrome generalized seizures

Most common of all seizures of childhood i.e. 70% (including most febrile convulsions)

(a) Grand Mal Seizure or Generalized Tonic-clonic Seizures. It shows the following features :

• G. S. are usually idiopathic and are associated with genetic factors
• In children, it generally occurs without warning
• Inhibition of respiration during tonic phase leading to cyanosis is common while fecal incontinence usually does not occur. Autonomic symptoms are common
• Precipitated by excessive fatigue or lack of sleep, infectious illness, fever or withdrawal of AEDs, some kids are sensitive to lights, music, noise which can lead to seizures

G. S. are rarely the initial or main manifestation of metabolic diseases.

Co-morbidity which precipitates seizures :

• Spasticity or microcephaly suggest preexisting neurologic disease.
• “Café au lait” spots or depigmented area Neurofibromatosis or Tuberous sclerosis can precipitate seizures
  Other precipitating factors

Increased head circumference – Hydrocephalus

Fundus EX showing – Recent trauma, Chorioretinitis (Congenital viral infection)

Hypernatremic Dehydration – Following diarrhea

Hyperglycemia and hypoglycemia are rare causes of G.S. and can be easily ruled out at time of seizure.

Diagnosis

EEG : Normal interictal EEG does not rule out seizure disorder conversely abnormal EEG, does not establish diagnosis of G. S. EEG can not replace clinical judgment, it may help to differentiate seizure with pseudoseizure.

Scan : Not indicated in G. S. with normal neurological examination

Drug of choice : Sodium valporate / phenytoin / phenobarbitone