Epidemiological and clinical studies of West syndrome in Nagasaki Prefecture, Japan

Recent advances in diagnostic and therapeutic techniques may have changed i ncidence and etiologies of West syndrome (WS). We performed a retrospective epidemiological study of WS that occurred in 47 children in Nagasaki Prefe cture during a recent 10-year period from 1989 to 1998. The incidence of WS was 3.1/10,000 live births. Thirty-nine, patients (83%) had symptomatic WS , in which the prenatal causes were most frequent, followed by low-birth we ight (LBW) infants, perinatal and postnatal. Such high frequency of LBW may have been due to a relative increase in survivors of premature babies beca use of recent advances in perinatal care. The brain computerized tomography /magnetic resonance imaging performed in 41 patients revealed congenital br ain malformation (10 patients), destructive brain disorders (13 patients), and no structural abnormalities (18 patients). The seizure outcome was wors e in the symptomatic WS than in the cryptogenic WS. The developmental outco me was very poor in both symptomatic and cryptogenic WS. The mean developme ntal quotient (DQ) in all patients was 25, and only four patients (11%) had a normal DQ (>70). DQ was lower in patients with developmental delay befor e the onset of WS, symptomatic group, relapse and/or persistence of seizure . Developmental delay seen in WS patients seems to be related to the two ma jor factors, that is, underlying brain abnormalities and the persistent sei zures as a result of the former. Therefore, every effort should be made to control seizures, including medical and early surgical treatment, as well a s prevention of brain damage through perinatal care. (C) 2001 Elsevier Scie nce B.V. All rights reserved.