PRENATAL ETIOLOGIES OF WEST SYNDROME

We investigated the etiology of West syndrome (WS) with special refere nce to prenatal factors in 180 cases. Prenatal cause was the most freq uent diagnosis (77 cases, 42.8%), followed by perinatal (25 cases, 13. 9%) and postnatal factors (12 cases, 6.7%); 48 cases (26.7%) were of u ncertain etiology; eighteen cases (10.0%) were idiopathic. Of the thre e forms of age-dependent epileptic encephalopathy, prenatal cause was present in 12 of 15 cases (80.0%) of early-infantile epileptic encepha lopathy with suppression-burst, 77 of 180 cases (42.8%) of WS, and 31 of 123 cases (25.2%) of Lennox-Gastaut syndrome (LGS). Prenatal factor s of WS included tuberous sclerosis (23), chromosome abnormalities (10 ), cerebral dysgenesis (10), porencephaly (7), hydrocephalus (5), Aica rdi syndrome (3), Aicardi syndrome associated with chromosome abnormal ity (1), and other causes (18). Chromosome abnormalities with WS consi sted of 6 cases with 21 trisomy and one case each with 18q duplication , t(1;y) translocation, 7q duplication, and partial 2p trisomy. One pa tient with Aicardi syndrome also had a t(12;21) translocation. No sign ificant difference was observed in the age of onset of WS among the fi ve etiologic groups. The evolution from WS to LGS was not influenced b y etiology, except for the idiopathic group. In patients followed for over 3 years, seizure remission occurred in 46.8% (22 of 47 cases) of the prenatal group. This was lower than the other four groups. Intelle ctual prognosis was also relatively poor in those with prenatal onset. Pyridoxal phosphate (PAL-P) treatment was effective in 9 of 70 (12.9% ) prenatal cases and 5 of 18 (27.8%) idiopathic cases. Notably, effica cy rates of 14.3, 14.8%, and 20.0% were observed in those with tuberou s sclerosis, brain malformation, and chromosome abnormality, respectiv ely. No significant difference in the effect of synthetic ACTH (Cortro syn-Z) was observed among the five groups. These findings suggested th at WS due to prenatal etiologies and those due to other etiologies are essentially homogeneous in age of onset and clinicoelectrical feature s, although each has some individual characteristics. We conjecture th at WS is one form of an age-specific epileptic reaction to diverse non specific exogenous insults.