benign infantile seizures a prospective study introduction one idiopathic focal epileptic syndrome with onset during infancy is recognized the benign infantile seizures bisobjective to analyze the electroclinical features and evolution in patients with bis and assess the difference between familial and nonfamilial infantile casespatients and methods we performed a prospective followup study in 41 patients seen at our department between september 2002 and march 2004 with bis from 2 to 12 months of age among the 41 cases 6 were excludedresults thirty five had bis after the followup the followup was 6077 months median 69 months they were divided in group 1 14 patients had a family history of similar seizures in infancy and group 2 21 without familial history of infantile epilepsy both groups have similar electroclinical features and family history of seizures is the only clue to the differential diagnosis seizures were brief and occurred in cluster in 30 patients 85 interictal eegs were normal in 34 cases 97 and neuroimaging in all children no one had seizures after finishing the antiepileptic treatment neurological examination and developmental milestones remained normal after the followupconclusions this study confirms the existence of bis nonfamilial cases might represent novo mutations or sporadic cases of bis the recognition of bis is possible at beginning of the epilepsy to confirm the syndrome the followup is necessary