In two cases of diencephalic syndrome with emaciation, very high fasting levels of plasma growth hormone (GH) were consistently found. Insulin injection and arginine hydrochloride stimulation did not always raise the hormone levels, and glucose loading resulted in incomplete suppression. Plasma insulin response to arginine stimulation and to glucose loading was blunted. Despite the presence of acromegalic levels of GH in the blood, longitudinal growth became as stunted as in other forms of malnutrition.
To study the relative roles of cerebral damage and malnutrition, the same investigations were carried out in other groups of patients. High plasma GH levels were only found during manifest hypoglycemia or hypoproteinemia, and in one case of cerebral damage complicated by malnutrition and hypertonic dehydration.