What is the value of growth hormone treatment in short children with specified syndrome? Turner's syndrome, osteochondrodysplasias, Prader-Willi syndrome, Noonan syndrome

Growth hormone secretion in Prader-Willi syndrome

Prader-Willi Syndrome (PWS) is a multisystem defect characterized by obesity, hypogenitalism and short stature for genetic background. Low GH serum levels have been found in patients with PWS and were related to a hypothalamic-pituitary dysfunction. We studied spontaneous nocturnal GH secretion and GH-response to provocative tests in five patients affected by PWS. We observed in three of them (Group A) abnormally low GH and IGF-1 serum levels. In the other two patients (Group B) GH secretion and IGF-1 serum levels were normal. In all patients no thyroid dysfunction was observed. These data might suggest the presence of two different subgroups of patients affected by PWS, from an endocrinological point of view. An abnormally low GH secretion would be evident only in a subgroup of patients, which appears to be normal in the remaining patients. This casistic is small in number, but if our data will be confirmed by more extensive studies it may be possible to identify a specific population of PWS patients who could benefit from recombinant GH-therapy.

Use and abuse of human growth hormone

Recombinant human growth hormone (hGH) has been available for nearly a decade. Side effects are rare. Its efficacy in promoting growth acceleration has been widely confirmed in children with GH deficiency (GHD), Turner syndrome, idiopathic short stature, chronic renal failure, and a variety of other conditions. The dramatic increase in height velocity in the first year of therapy partially attenuates in subsequent years in all patient groups, and convincing final height data are only available in GHD and Turner syndrome. Pediatric endocrinologists continue to be troubled by definitions of GHD. Although profound GHD is relatively obvious, other patients with severe growth failure but borderline or normal endocrine testing also respond to hGH therapy. Thus many endocrinologists use auxologic criteria [e.g. low growth velocity, height < -3 standard deviation (SD), poor predicted adult height] as the de facto basis for therapy, leading to a blurred distinction between treatment of disease and enhancement of normal characteristics and, finally, raising questions about the ultimate benefit of hGH therapy. Brief clinical trials of hGH therapy in adults both with and without GHD have reported increased muscle mass, decreased fat, and improvement in quality of life. Internists may soon be faced with treatment decisions analogous to those confronting pediatricians, i.e. whether to use hGH to repair aspects of the normal aging process.