ANTERIOR HYPOPITUITARISM DUE TO AGENESIS OF THE PITUITARY-STALK

Congenital hypopituitarism occurs in approximately 1 of 100 000 births. Clinical manifestations include hypoglycemia, micropenis, and deficient production of the anterior pituitary hormones of variable severity, with no diabetes insipidus. Biologic findings point to hormone deficiencies due to a pituitary or hypothalamic cause, with in the latter case increased basal serum prolactin levels and an increased delayed TSH response to TR. Magnetic resonance imaging should now be routinely performed and may disclose hypoplasia of the anterior pituitary, agenesis of the pituitary stalk, and ectopia of the posterior pituitary which is located immediately below the median eminence. An illustrative case is reported herein. Congenital hypopituitarism may be difficult to differentiate from idiopathic hypopituitarism which occurs at a later age and may be secondary to perinatal injury. The same anomalies may be found in both forms. Congenital and idiopathic hypopituitarism may be manifestations of differing severity of the same disease process.