Secondary diabetes mellitus in Prader-Willi syndrome

Objective Prader-Willi Syndrome (PWS) is a rare autosomal dominant disorder on the 15q11.2-q13 chromosome. PWS may impact metabolic, endocrine, and neurologic systems and combine with hypotonia, sleep disturbances, cognitive disability, central adrenal insufficiency, hypothyroidism, hypogonadism, short stature, and other diseases. Methods Here ,we report a PWS patient with secondary diabetes mellitus. Clinical and laboratory features are summarized. Results The patient had typical manifestations of PWS including almond-shaped eyes, narrow temples, narrow nasal bridge, and short hands and feet. Lab test revealed hypogonadism and growth hormone deficiency. SNP array revealed one copy of chromosome 15 q11.2q13.1 was missing, with a length of about 6.4 mbp. Conclusions This case emphasizes the importance of considering PWS in the differential diagnosis of an adolescent with diabetes. Antenatal history of neonatal hypotonia and childhood history of feeding disorder are the keys to the diagnosis of PWS.