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It is also important to classify the type of seizure as it may give a clue to the cause of the seizure disorder and may allow the physician to prognosticate a response to treatment and the future outlook of the patient, for example, the child with Rolandic epilepsy has an excellent prognosis and is unlikely to acquire long term anticonvulsants.

Clinical features of epileptic syndromes

Neonatal period

• Benign Neonatal seizures: These are repetitive seizures between 4-6 days of life, which subsequently remit. Prognosis is good.
• Benign familial Neonatal seizures: This is an autosomal dominant inheritance. Convulsions occur in the first week of life and remit in a few months.
• Early myoclonic encephalopathy: EEG shows the classical feature of suppression alternating with bursts of spike sharp and slow wave activity. It is usually associated with severe neurological abnormalities and early death.

• Benign myoclonic epilepsy of infancy: This begins in infancy and consists of clusters of myoclonic movement usually involving the neck, trunk and extremities. Prognosis is good and cessation usually occurs by 2 years. A familial autosomal dominant form is thought to be linked to a locus on chromosome 20.
• Severe myoclonus of infancy: In a previously normal child, this usually starts with unilateral or bilateral clonic seizures followed later by myoclonic jerks which supervene and may be associated with partial seizures, with autonomic or anotic features, and automatisms. These seizures are usually refractory to treatment and developmental arrest may supervene.
• West syndrome: This occurs between 3 months to 1 year of age and consists of a triad of
  
  
  • nfantile spasm
  • Hypsarrythmia in EEG.
  • Mental retardation.
    
  It may be symptomatic following a known insult like hypoxic ischaemic encephalopathy or any other perinatal insult, infection, metabolic derangements etc. These account for 70-80% of West Syndrome. The remaining 20-30% in which no obvious cause is delineated are classified as cryptogenic.2

Early childhood(1-5 years)

• Febrile seizures
  
  This occurs between 3 months to 5 years. A family history is present in 10% of patients. A typical febrile seizure is brief, generalized tonic-clonic, usually with rising fever or at the spike of fever and occurs in a child with normal development. It lasts for less than 5-10 minutes and is not associated with any abnormal neurologic signs.
  
  Atypical febrile seizures on the contrary include those that last for more than 15 minutes, are repeated convulsions or are focal seizures. Approximately 50% of children may have recurrent febrile seizures. The risk of development of epilepsy is 1% in children without risk factors and increases to 9% in the presence of risk factors like positive family history of epilepsy. Initial febrile seizure prior to 3 months of age, prolonged or atypical febrile seizure, delayed milestones or abnormal neurologic examination3.
  
• Lennox-gastaut syndrome
  
  These are neurologically abnormal children and may manifest with atypical absence, myoclonic and tonic seizures with progressive mental deteriorations. They usually occur between 2-8 years and are seen more frequently in males. Treatment is difficult and these are usually resistant to anticonvulsants.
• Myoclonic astatic
  
  These children have a normal development with no neurological deficit before onset. The seizures are usually primarily generalised myoclonic, astatic, short absence with myoclonic jerks and generalised tonic-clonic. Spontaneous remission may occur but 50% continue to have seizures.

Late childhood (5-10 years)

• Childhood absence
  
  These are common in females. These seizures are short in duration with abrupt onset and termination and have a high frequency of seizures per day. Consciousness is impaired and total amnesia of the event is present. An easy bedside method to reproduce the seizure is to ask the patient to hyperventilate for 2-3 minutes, which precipitates the seizure. EEG is diagnostic with bilateral, symmetrical,synchronous discharge of spike and wave at 3 cycles per second with a normal background activity.
  
• Benign partial epilepsy with centerotemporal spike or Rolandic epilepsy
  
  BPEC occurs between 2-14 years with a peak at 9-10 years. It occurs in normal children with a unremarkable past history and a normal neurologic examination. A positive family history of epilepsy or abnormal EEG is seen in 40 % of cases. Seizures are usually focal and involve the face and oropharynx with speech arrest, guttural sounds and drooling. BPEC occurs in sleep in 75% of patients and up to 25% have repeated clusters of seizures. Carbamazepine is the preferred drug which is continued for at least 2 years or until 14-16 years of age when spontaneous remission of BPEC occurs. EEG is diagnostic and consists of large diphasic , high voltage centerotemporal spikes, followed by slow waves seen in clusters with a normal background activity.