Prognostic factors in epileptic encephalopathies at onset in the first 2 years of life: The experience of a tertiary healthcare center in Italy.

•We propose for epileptic encephalopathy prognostic factors for multiple outcome measures.•Neurological development before the onset represents a major prognostic factor, as for survival as for neuroevolutive state.•Structural aetiology is associated with drug resistance and global development impairment.•In patients with epileptic encephalopathies, perinatal diseases predict the worst prognosis.•Lack of response to antiepileptic drug within three months are correlated with a severe long-term prognosis.