Denoument and Discussion
Prader-Willi Syndrome
Manifestations
The major manifestations of the Prader-Willi syndrome consist of obesity, short stature, hypogonadism, hypotonia, and mental retardation. There may be a history of intrauterine inactivity. Present during the neonatal period are a poor sucking reflex, difficulty in swallowing, a weak cry, failure to thrive, abnormal temperature regulation, and an amyotonia-like picture which gradually improves. By 2 or 3 years of age, obesity becomes prominent with the face, lower trunk, and buttocks more involved than the rest of the body. Brachycephaly and dolicocephaly and a prominent low forehead are present. The typical facial appearance includes a rounded face, fish-like mouth, almond-shaped eyes, strabismus, and micrognathia. Genital abnormalities consist of a small penis, cryptorchidism or small testes, hypoplastic scrotum or labia, and delayed secondary sexual characteristics. Hyperphagia is frequently present in later childhood, and diabetes mellitus may occur during puberty. Skeletal abnormalities include small hands and