Adrenal response to ACTH in patients with Prader-Willi syndrome, simple obesity, and constitutional dwarfism.

In 1956 Prader, Labhart, and Willi first described a group of patients who presented with 'floppiness' at birth and later became obese, dwarfed, and mentally retarded, and some had impaired glucose tolerance tests. Further articles followed (Prader and Willi, 1961; Laurance, 1961, 1967; Forssman and Hagberg, 1964; Evans, 1964; Hooft, Delire, and Casneuf, 1966). Laurance gave a detailed description of the syndrome. The features which he considered characteristic were obesity, mental retardation, hypogonadism, hypotonia, shortness of stature, prominent forehead, almond-shaped eyes, retrousse nose, small fish-like mouth, short hands and feet. All of them were floppy at birth and some of them showed a diabetic type of glucose tolerance test. Laurance concluded that the adrenal function was normal in these patients, but Forssman and Hagberg reported a reduced response to ACTH. In the present paper we report a comparison of the plasma cortisol response to ACTH in 22 subjects, 6 of whom were children showing the features of Prader-Willi syndrome as described above. Of the remainder, 6 were children with constitutional short stature, 4 were children with simple obesity, and 6 were healthy adolescents with no known metabolic disease. Evidence is also presented from the results of long-term ACTH (3 days) in 2 cases of Prader-Willi syndrome that the urinary 17-OHCS output parallels their plasma cortisol response.