We describe the case of a 16-month-old girl with congenital hyperinsulinism diagnosed at the age of 11 months, after a history of a single convulsive seizure at 4 months of age, followed by frequent unexplained paroxysmal events related to sleep. The diagnosis was made when a second convulsive seizure occurred and a severe hypoglycemia was detected. Since the treatment with diazoxide was started, both seizures and sleep disorder disappeared. This case support the recommendations of the literature to consider a congenital hyperinsulinism even in cases of infantile convulsions apparently “benign” and/or in the evaluation of atypical motor or behavioral paroxysmal manifestations of uncertain origin; in this field, the correlation of hypoglycemia with sleep is a current topic of discussion and remains to be clarified.
