A 5-year-old previously healthy boy is brought to the pediatric neurology clinic with progressive loss of language comprehension over 2 months. His parents report he no longer understands spoken instructions, though hearing assessment is normal. He has become hyperactive and inattentive. Occasional focal seizures have been noted. EEG shows the pattern marked **B** in the diagram—continuous spike-and-wave discharges during sleep with a spike-wave index of 88% during NREM sleep, with bilateral temporal predominance. Which of the following is the MOST appropriate first-line management for this EEG abnormality?

Question

Accepted Answer

B. High-dose oral prednisolone (2–4 mg/kg/day) or IV methylprednisolone pulses. ## Why high-dose corticosteroids is right

Landau-Kleffner Syndrome (acquired epileptic aphasia) is characterized by progressive loss of language skills (auditory verbal agnosia) in a previously normal child, typically aged 3–8 years, in association with continuous spike-and-wave discharges during sleep (CSWS)—defined as spike-wave index >85% during NREM sleep. The EEG pattern marked **B** (CSWS with bilateral temporal predominance) is the hallmark electrographic finding. The pathophysiology involves continuous epileptiform activity disrupting the auditory association cortex (Wernicke's area) during critical developmental windows. High-dose corticosteroids (oral prednisolone 2–4 mg/kg/day or IV methylprednisolone pulses) are the established first-line treatment and can produce dramatic recovery of language function if started early, particularly when the EEG abnormality is aggressively suppressed. (Nelson Textbook of Pediatrics 22e—Epileptic Encephalopathies)

## Why each distractor is wrong

- **Carbamazepine monotherapy**: Carbamazepine and phenytoin are CONTRAINDICATED in LKS because they may paradoxically worsen or fail to suppress CSWS, potentially exacerbating language decline.
- **Levetiracetam combined with phenytoin**: While levetiracetam is an acceptable alternative AED in LKS, combining it with phenytoin is inappropriate because phenytoin worsens CSWS and is not first-line. Additionally, this combination does not address the primary pathology (continuous epileptiform discharges) as effectively as corticosteroids.
- **Ethosuximide as sole therapy**: Although ethosuximide may be used as an adjunctive AED in some cases, it is not first-line monotherapy for LKS and lacks the immunomodulatory and anti-inflammatory properties necessary to suppress CSWS and promote language recovery.

**High-Yield:** In Landau-Kleffner Syndrome, aggressive suppression of CSWS with high-dose corticosteroids is first-line and correlates with better language recovery; avoid carbamazepine and phenytoin which worsen the EEG abnormality.

[cite: Nelson Textbook of Pediatrics 22e—Epileptic Encephalopathies]

Answer

A. Ethosuximide as sole therapy for spike-wave suppression

Answer

C. Levetiracetam combined with phenytoin for seizure control

Answer

D. Carbamazepine monotherapy with gradual titration

Explanation

Why high-dose corticosteroids is right

Why each distractor is wrong

Practice similar questions