Self-Limited Epilepsy with Centrotemporal Spikes

Self-limited epilepsy with centrotemporal spikes (formerly benign rolandic epilepsy) is the commonest focal epilepsy of childhood. It causes brief, mostly nocturnal focal seizures of the face and mouth, with centrotemporal spikes on EEG, and remits by mid-adolescence.

It accounts for about 15% of childhood epilepsy, with an incidence of about 6 to 21 in every 100,000 children each year. Onset is between 3 and 13 years, with a peak at 7 to 10, and boys are slightly more affected.

Genetics. Family history of epilepsy or febrile seizures is common, and the EEG trait is inherited. Rare variants in GRIN2A are linked to the severe end of the spectrum.

Course. Most children have few seizures and are seizure free by 15 to 16 years. A small proportion evolve to atypical forms, with developmental or language regression and continuous spike wave in sleep.

Pathophysiology.

A maturation dependent hyperexcitability of the sensorimotor cortex around the rolandic fissure produces focal discharges, which are activated by sleep.

Genetic susceptibility to age limited cortical excitability explains spontaneous remission as networks mature.

• Seizures arise mainly from sleep, often on waking: unilateral facial twitching, drooling, guttural sounds, and speech arrest with preserved awareness.
• Secondary generalisation to a tonic clonic seizure at night in many.
• Few seizures in total, often under 10, and sometimes only 1 or 2.
• Normal neurological examination and development.

Red flags.

• Daytime seizures that are frequent, or atypical features such as atonic seizures or negative myoclonus.
• Language, behaviour or cognitive decline.
• Focal neurological signs or abnormal MRI.

• Clinical history of typical nocturnal hemifacial seizures; EEG shows high amplitude centrotemporal spikes that increase in sleep, on a normal background.
• MRI is not needed when the picture is typical; it is done for atypical features, focal signs or a very young age.
• Sleep EEG when regression is suspected, to exclude continuous spike wave in sleep.
• Neuropsychological and school assessment.

Differential diagnosis. Panayiotopoulos syndrome, focal structural epilepsy, atypical evolution with continuous spike wave in sleep, Landau-Kleffner syndrome, parasomnias and syncope.

• Many children need no antiseizure drug, because seizures are infrequent, nocturnal and self-limited; give family education on first aid and recognition.
• Treatment is considered for frequent seizures, daytime events, injury risk or parental preference.
• Levetiracetam for age 4 to 11 years or weight under 50 kg: 10 mg/kg orally daily in 2 divided doses, increased by 10 mg/kg daily every 2 weeks to a usual 20 to 30 mg/kg daily. Maximum 30 mg/kg twice daily (60 mg/kg daily). Monitor behaviour, irritability, mood and renal function. Reduce dose in renal impairment (creatinine clearance under 80 mL/min); use caution in pregnancy and breastfeeding.
• Lamotrigine as an alternative, for age 2 to 11 years: 0.3 mg/kg orally daily in 1 or 2 doses for 2 weeks, then 0.6 mg/kg daily for 2 weeks, then increases of 0.6 mg/kg every 1 to 2 weeks to a usual 1 to 10 mg/kg daily. Maximum 200 mg daily. With valproate: 0.15 mg/kg once daily for 2 weeks, then 0.3 mg/kg daily for 2 weeks, then increases of 0.3 mg/kg every 1 to 2 weeks to a usual 1 to 5 mg/kg daily. Monitor for rash, hypersensitivity and Stevens-Johnson syndrome (stop at the first rash). Reduce dose in moderate to severe hepatic impairment; levels fall with oestrogen containing contraception and in pregnancy.
• Avoid carbamazepine and oxcarbazepine in atypical variants because they can aggravate spike wave activity.
• Treatment is usually stopped after 1 to 2 years seizure free and by about age 14 to 16.

Monitoring. Review every 6 to 12 months; repeat EEG if regression or new seizure types appear; monitor school performance.

Referral and escalation. Paediatric neurology for atypical features, daytime seizures, regression, or failure of one drug; urgent review for evolution to continuous spike wave in sleep.

Special groups. Adolescents: counsel on sleep and driving; most outgrow the condition.