Clinically silent congenital adrenal hyperplasia masquerading as ectopic adrenocorticotropic hormone syndrome.

A 64-year-old man with an asymptomatic pulmonary mass discovered on routine chest roentgenography was found to have substantial bilateral adrenal enlargement by abdominal computed tomography. Percutaneous adrenal aspiration biopsy showed cytologically normal adrenal glands. A diagnosis of subclinical 21-hydroxylase deficiency was established by stimulation testing with adrenocorticotropic hormone. The adrenal size and appearance by computed tomographic scanning in congenital adrenal hyperplasia and particularly in its subclinical form have not been well defined. This case demonstrates that marked adrenal enlargement can occur and may provide the only clue to the diagnosis in an asymptomatic patient without other clinical stigmata of adrenal hyperplasia.