Question

A 2-year-old child presents with status epilepticus and a history of 4–5 prior seizure episodes, both focal and myoclonic. EEG shows 1–2 Hz spike-wave complexes. What is the most probable diagnosis?

• A. Lennox-Gastaut syndrome
• B. Subacute sclerosing panencephalitis (SSPE)
• C. West syndrome
• D. Rolandic epilepsy

Hint:

Lennox-Gastaut Triad:
1. Multiple intractable seizure types (Tonic, Atonic, Atypical Absence, Myoclonic)
2. Cognitive impairment neurodevelopmental regression
3. Slow spike-and-wave discharges ($<2.5\text{ Hz}$, usually $1.5\text{--}2\text{ Hz}$) on EEG.

Answer 1

The Correct Option is A

Concept:
Lennox-Gastaut Syndrome (LGS) is a severe, refractory developmental and epileptic encephalopathy of early childhood.
It is defined clinically by a classic diagnostic triad consisting of polymorphic intractable seizures, intellectual impairment/cognitive dysfunction, and a characteristic slow spike-and-wave pattern on electroencephalography (EEG).
Explanation:
• Lennox-Gastaut syndrome typically manifests between 2 and 8 years of age, often evolving from infantile spasms (West syndrome).

• The syndrome features multiple seizure types occurring in the same patient, including tonic seizures (especially during non-REM sleep), atonic/drop attacks, atypical absences, myoclonic jerks, and episodes of non-convulsive status epilepticus.

• The pathognomonic interictal EEG finding is generalized slow spike-and-wave complexes at a frequency of $<2.5\text{ Hz$ (typically $1.5\text{--}2.0\text{ Hz}$)}, often accompanied by paroxysmal fast activity ($10\text{--}20\text{ Hz}$) during sleep.

• West syndrome presents earlier in infancy ($3\text{--}12\text{ months}$) with epileptic spasms, developmental arrest, and an EEG pattern of hypsarrhythmia (chaotic, high-voltage, disorganized slow waves).

• Subacute sclerosing panencephalitis (SSPE) occurs years after measles infection in older children and presents with periodic, high-amplitude, stereotyped slow-wave complexes (Radermecker complexes).

• Self-limited (benign) Rolandic epilepsy presents with nocturnal focal orofacial motor seizures and centrotemporal spikes on a normal background EEG without status epilepticus or cognitive decline.
Final Answer:
The clinical presentation of intractable polymorphic seizures, status epilepticus, and an EEG demonstrating slow ($1\text{--}2\text{ Hz}$) spike-wave complexes confirms Lennox-Gastaut syndrome.