[Clinical screening and genetic diagnosis for Prader-Willi syndrome].

OBJECTIVE To study the clinical screening and genetic diagnosis of children suspected of Prader-Willi syndrome (PWS), as well as the differences in the scores of clinical diagnostic criteria among the children with a confirmed diagnosis of PWS. METHODS A total of 94 children suspected of PWS who were admitted from July 2016 to December 2018 were enrolled as subjects. Methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) was performed to confirm the diagnosis. For the children with a confirmed diagnosis of PWS, the scores of clinical diagnostic criteria were determined, and the perinatal characteristics were analyzed. RESULTS A total of 11 children with PWS were confirmed by MS-MLPA, with a detection rate of 12%, among whom there were 7 boys and 4 girls, with a median age of 3 years and 4 months (range 25 days to 6 years and 8 months) at the time of confirmed diagnosis. Among the 11 children with PWS, only 5 children (45%) met the criteria for clinical diagnosis. The main perinatal characteristics of the children with PWS were decreased fetal movement (9 cases, 82%), cesarean section birth (11 cases, 100%), hypotonia (11 cases, 100%), feeding difficulties (11 cases, 100%), and weak crying (11 cases, 100%). CONCLUSIONS Gene testing should be performed as early as possible for children suspected of PWS by clinical screening. PWS may be missed if only based on the scores of clinical diagnostic criteria.