Somatropin therapy for children with prader-willi syndrome : guidelines for use.

Prader-Willi syndrome is a neurogenetic disorder that occurs due to the lack of a paternally expressed gene or genes on chromosome 15q11-q13. Many of the symptoms present in Prader-Willi syndrome are due to a hypothalamic-pituitary dysfunction. The main characteristics are muscular hypotonia, delayed psychomotor development, insatiable appetite resulting in overweight if a diet is not maintained, compromised growth and puberty resulting in a short final height and incomplete sexual development, respiratory disturbances, and dysmorphic features. Individuals with Prader-Willi syndrome have compromised growth and abnormal body composition with increased fat mass, decreased lean body mass, and low bone density, resembling a growth hormone-deficient status. Somatropin treatment has a beneficial effect on growth with increased final height and an improvement in and maintenance of body composition, as well as a beneficial effect on respiratory functions. Before initiating somatropin therapy, weight should be kept at an appropriate level, and polysomnography, as well as an otorhinolaryngologic examination should be performed. During somatropin therapy, carbohydrate metabolism and the development of scoliosis should be monitored, as well as bodyweight.A comprehensive team to manage the various components of medical, psychologic, and sociologic care is required for individuals with Prader-Willi syndrome.