Seizure Disorders USMLE Step 1 Practice Question
A 9-month-old infant presents with sudden onset of brief flexion of the trunk and extremities occurring in clusters, followed by crying. Episodes last 1-2 seconds and occur 10-15 times daily. Vital signs: HR 128/min, RR 26/min, BP 95/60 mmHg, temp 37.2°C, SpO2 98%. EEG demonstrates hypsarrhythmia with high-amplitude disorganized activity. Serum glucose and metabolic panel are normal. No fever or recent illness reported. Which diagnosis best explains these findings?
Answer choices
- AInfantile spasm (West syndrome)Correct answer
- BMyoclonic-astatic seizure
- CFebrile seizure
- DGeneralized tonic-clonic seizure
- EAbsence seizure
- FBenign sleep myoclonus of infancy
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