Seizure Disorders in Children Dr. Pushpa Raj Sharma FCPS Professor of Child Health Institute of Medicine Definitions Seizure: A sudden, involuntary, time-limited alteration in behavior, motor activity, autonomic function, consciousness, or sensation, accompanied by an abnormal electrical discharge in the brain Definitions Epilepsy: A condition in which an individual is predisposed to recurrent seizures because of a central nervous system disorder Status Epilepticus: More than thirty minutes of continuous seizure activity, or recurrent seizures without intercurrent recovery of consciousness Prevalence No data available in Nepal. Seizure disorders: 360/100,000 (India, Saha SP 2003). Prevalence of seizure disorder in children has been reported to be 350/100,000 (Gortmaker and Sappenfield, 1984). However, 3-5% of all children will have one or more seizures (Haslem, 2000). The incidence of epilepsy (new cases per year) has been reported to be 50/100,000, with 75% of people developing epilepsy doing so prior to 20 years of age (Holmes, 1992) Burden of the problem Per 100,000 people, there will be: 86 seizures in the first year of life 62 seizures between 1 and 5 years 50 seizures between 5 and 9 years 39 seizures between 10 and 14 years In over 65% of patients, epilepsy begins in childhood. Recurrent seizures during fever in an 24 month old History A 24 month old boy was seen in the KCH emergency room following a seizure accompanied by fever, his second in 6 months. The child had been well until the previous day, when parents notices fever for which he was take to a doctor who prescribed amoxicillin for the diagnosis of URTI. The following morning, the boy experienced a 2 minute generalized stiffness just as father was administering amoxicillin. Afterwards, he was rushed to the KCH.The child resumed normal alertness on way to the hospital. Prior seizures had occurred at the ages of 18 and 20, months with fever in each instance. Prior seizures were otherwise identical in duration and character. Past medical history was noncontributory. Development was normal, with independent walking at 12 months and present use of single sentences. Review of family history revealed that an older sister had suffered from similar seizures during fever until age 3. Recurrent seizures during fever in an 24 month old Physical Exam In the emergency room, the boy was alert and appeared only minimally ill. Temperature was 38.4. General physical exam revealed a dull and erythematous left tympanic membrane and mild cervical adenopathy. No nuchal rigidity or other meningeal signs were apparent. Neurologic examination was entirely nonfocal and the child's motor skills, language, and social interaction seemed normal for age. DETAILED HISTORY OF THE CHILD WITH CONVULSION • Mode of onset of convulsion, character, duration, any similar previous history (chronic/recurring). • Triggering factors- fever, toxic substance or drug, metabolic dis- turbance. • Family history of convulsion, inborn error of metabolism. • Peri-natal/Natal history-birth asphyxia, jaundice, birth trauma, central nervous system (CNS) infection e.g. meningitis, encephalitis etc. • CNS status-cerebral palsy, mental retardation (learning difficulty), any post-convulsive state. CONVULSION IN INFANTS AND OLDER CHILDREN A) Acute/Non-recurring (i) with fever: febrile convulsion, infections e.g. meningitis, encef)halitis. . (ii) without fever: poisoning including medicinal overdose, metabolic disturbance e.g. hypoglycaemia, hypocalcaemia and electrolyte imbalance, head injury, brain tumour, epilepsy. B) Chronic/Recurring : (i) with fever: recurrent febrile convulsion, recurrent meningitis. (ii) without fever: epilepsy. Febrile seizures Febrile convulsions, the most common seizure disorder during childhood. Age dependent and are rare before 9 mo and after 5 yr of age. A strong family history of febrile convulsions. Usually generalized, is tonic-clonic and lasts a few seconds to 10-min Mapped the febrile seizure gene to chromosomes 19p and 8q13-21. Atypical febrile seizures The duration is longer than 15 min. Repeated convulsions occur within the same day. Focal seizure activity or focal findings are present during the postictal period. Treatment of febrile seizures A careful search for the cause of the fever. Use of antipyretics. Reassurance of the parents. Prolonged anticonvulsant prophylaxis for preventing recurrent febrile convulsions is controversial and no longer recommended. Oral diazepam, 0.3 mg/kg q8h (1mg/kg/24hr), is administered for the duration of the illness (usually 2–3 days). Classification of Epileptic Seizures Partial seizures: Simple partial (consciousness retained) Motor Sensory Autonomic Psychic Complex partial (consciousness impaired) Simplepartial, followed by impaired consciousness Consciousness impaired at onset Partial seizures with secondary generalization Source: Nelson”s Textbook of Pediatrics, (17th ed.) Classification of Epileptic Seizures Generalized seizures Absencess Typical Atypical Generalized tonic clonic Tonic Clonic Myoclonic Atonic Infantile spasms Unclassified seizures Source: Nelson”s Textbook of Pediatrics, (17th ed.) Mimicking seizures Benign paroxysmal vertigo Night terrors Breath-holding spells Syncope Paroxysmal kinesigenic Choreoathetosis Shuddering attacks Benign paroxysmal torticollis of infancy Hereditary chin trembling Narcolepsy Rage attacks Pseudo seizures Masturbation Status Epilepticus Three major subtypes: prolonged febrile seizures idiopathic status epilepticus symptomatic status epilepticus Higher mortality rate. Severe anoxic encephalopathy in first few days of life. History. The relationship between the neurologic outcome and the duration of status epilepticus is unknown in children. Treatment of status epilepticus Initial treatment: assessment of the respiratory and cardiovascular systems; A nasogastric tube insertion; IV catheter; a rapid infusion of 5 mL/kg of 10% dextrose; blood is obtained for a CBC and for determination of electrolytes. a physical and neurologic examination. Source: Nelson”s Textbook of Pediatrics, (17th ed.) Treatment of status epilepticus Drugs: should always be administered IV; phenytoin forms a precipitate in glucose solutions; have resuscitation equipment at the bedside; A benzodiazepine (diazepam) may be used initially; if the seizures persist, phenytoin is given immediately The choices for further drug management include paraldehyde, a diazepam infusion, barbiturate coma, or general anesthesia.