Craniopharyngiomas are the most common tumors causing hypopituitarism. Infants with intrauterine hypopituitarism may present at birth with hypoglycemic seizures, prolonged jaundice, and, if male, micropenis and undescended testes. Because the majority of affected patients have idiopathic hypopituitarism, growth failure is often apparant by the end of the first year of life. The physician should be suspicious of an intrasellar or suprasellar tumor in patients whose growth failure does not begin until they are several years old. Hypopituitary children are proportioned normally for age, have a prominant calvarium, and tend to be overweight for height, and have prominant subcutaneous deposits of abdominal fat.
Many affected children fail to undergo puberty at the appropriate age.
Because adrenal secretion of mineralocorticoids is not dependent on pituitary ACTH, hypopituitary children rarely have electrolyte imbalance. Diabetes insipidus and hypothyroidism are rare in patients with idiopathic hypopituitarism. Delay in skeletal maturation is almost invariable, and a considerable number of children have heights for bone age which fall below the third percentile. In contrast to constitutional growth delay, the degree of bone age retardation in many cases of growth hormone deficiency is insufficient to account completely for the height deficit. In children who are underweight for height, a chronic systemic disease is more likely.