Acromegaly

Three years ago, the young man pictured here was told that he might have acromegaly, but he ignored this warning. Now, at age 32, he consulted an endocrinologist because he realized his facial features (A) and voice were becoming increasingly coarse. Soft-tissue swelling of his hands was also noted (B). Laboratory studies showed that the patient's serum level of insulin-like growth factor-1 (IGF-1, formerly known as somatomedin C) was 1,121 ng/mL (normal, 114 to 492 ng/mL). MRI of the sella turcica demonstrated a 3-cm macroadenoma (C) that elevated the optic chiasm.

Acromegaly is caused by hypersecretion of growth hormone by the pituitary gland after skeletal maturation. (Such hypersecretion before skeletal maturation is termed “gigantism.”) The face, hands, and feet are affected, as was the case with this patient. Other problems include excessive perspiration, thickening of the tongue, cartilaginous enlargement in the larynx (which deepens the voice), degenerative arthritis, and visceral organomegaly. Hyperphosphatemia and impaired glucose tolerance may be present. Growth hormone is lactogenic; patients with acromegaly therefore may lactate-even in the absence of hyperprolactinemia.

The diagnosis is made by measuring serum IGF-1 levels, and MRI is the modality of choice for localizing the pituitary adenoma. Dr Joel M. Schwartz of Nyack Hospital in Nyack, New York, writes that functioning adenomas (75% of the total) usually present earlier than nonfunctioning adenomas (which make up the remaining 25%). The former are most commonly prolactinomas, followed in frequency by adenomas that produce growth hormone or corticotropin. Management of acromegaly is multimodal and includes transsphenoidal hypophysectomy, radiation therapy, and-if necessary-bromocriptine.

This patient underwent surgery. He was given hormone therapy to manage the ensuing panhypopituitarism. There was a marked decrease in swelling of the hands, face, and tongue, and in shoe size.