Incidence of epilepsy in extremely low-birthweight infants (< 1,000 g): A population study of central and southern Sardinia

With the development of intensive care, the survival of extremely low-birthweight (ELBW) infants (< 1,000 g) has greatly improved. The aim of our study was to report the incidence of epilepsy after a follow-up of > 7 years in a population of ELBW children, born in central and southern Sardinia between 1991 and 2000. We analyzed data of 104 children. All infants had had serial cranial ultrasound echography (CUE) in the neonatal period and some also had magnetic resonance imaging (MRI). At last follow-up we evaluated the occurrence of epilepsy through a review of clinical charts and a structured telephone interview. In 11 (10.6%) of 104 of children we observed febrile seizures (FS). Epilepsy occurred in 9 (8.6%) of 104 ELBW children, and in these patients a frequent positive family history for epilepsy and/or FS was present. In four epilepsy patients CUE was highly pathologic, showing intraventricular hemorrhage (IVH) of grade IV and in two mildly abnormal (IVH of grade I-II). In three additional children with normal neonatal ultrasound scan, a later magnetic resonance imaging (MRI) study revealed lesions related to neonatal insult. In our ELBW population, epilepsy had an incidence clearly superior to that expected in infancy (8.6% vs. 0.6-0.8%). A frequent positive familiar history for epilepsy and/or FS suggests that a genetic predisposition may also play a role. Subjects with highly abnormal CUE are a subgroup with high risk for seizures; however, epilepsy can occur even with normal CUE.