[Urological problems in Prader-Willi syndrome].

Prader-Willi syndrome is rather a rare disease. However, as it includes 4 features (hypogonadism, hypomentia, hypotonia, and obesity), urologist may see the patients with this syndrome for their gonadal problem. We studied all the 27 cases in our hospital of which data were precisely collected. Among males, 67% of patients had presented themselves first to the department of pediatric internal medicine. One third of the patients were not diagnosed as the syndrome and referred to our clinic because of urological abnormalities. Chromosomal abnormality was seen in 40.9%. We found cryptorchism in all the cases and micropenis in 56%. In females, delayed menarche over 15-year-old was seen in 75%. From endocrinological studies, 75% male showed low reaction against HCG stimulation. Low gonadotropin responses to LH-RH were seen in 80% of all patients. We performed orohiopexy for cryptorchism, but testicular development was poor. And we do not actively utilize hormonal therapies for these patients.