Background: Infantile-onset epilepsy (excluding infantile spasms) is a poorly understood entity in terms of etiology, prognosis and optimal evaluation. We sought to study clinic-etiological profile, predictors of etiology and seizure control in this group.

Study design and setting: Prospective observational study at tertiary care pediatric center over one year (may 2012-June 2013)

Results: A total 88 children with onset of epilepsy between 2-24 months were enrolled. Mean age of onset 7.27 months (± 4.97); male:female ratio 1.4:1. A definitive cause could be identified in 45 children (51%): 40 were structural, 5 were genetic causes. Commonest structural causes were: static encephalopathies (16/40), and malformations (10/40), and neurocutaneous syndromes (4/40). Neuroimaging was an important predictor of cause: 36/42 patients with abnormal neuroimaging had confirmed etiological diagnosis. Metabolic work-up identified cause in 4 of 10 children (40%) with normal neuroimaging. Good seizure control seen in 31 children at last follow-up (6-12 months). Good response to first drug and requirement of 2 or less drugs predicted good seizure control. Fourteen of 88 (16%) later developed infantile spasms. Prior developmental delay, requirement of 3 or more drugs for seizure control and normal neuroimaging were significant predictors of conversion to infantile spasms.

Conclusion: Infantile epilepsy was of unknown etiology in 49% cases. MRI brain should be first investigation. Static encephalopathies and malformations are commonest causes. Children with normal neuroimaging should undergo metabolic work up. Large, multi-center prospective studies with tailored genetic testing are needed to better understand etiology, appropriate drugs and long-term prognosis.