Lesch-Nyhan syndrome in Japan

An epidemiological survey of Lesch-Nyhan (L-N) syndrome in Japan was carried out. In the first survey, questionnaires were mailed to the pediatric departments of the university hospitals, homes for mentally retarded children, and city and county medical associations. This study disclosed 41 patients with L-N syndrome and 48 with suspected L-N syndrome. In the second survey, questionnaires were mailed to the institutes that reported cases or suspected cases of L-N syndrome. In 29 of these cases, hypoxanthine-guanine phosphoribosyltransferase (HPRT) activity in the patients' erythrocytes was measured. Three cases were confirmed to be L-N syndrome in this study. Among the other confirmed cases, the activities of HPRT had already been determined in 23 cases. In addition to these cases, 10 cases have been reported in the literature, and 16 cases were considered to be with L-N syndrome from their typical clinical features without any determination of HPRT activity.