Severe Osteopenia in Young Adults Associated with Cushing's Syndrome Due to Micronodular Adrenal Disease

We report the association of severe osteopenia with Cushing's syndrome due to micronodular adrenal disease in 2 young adults. Except for the osteopenia, other clinical manifestations of the disease were not striking. In each case, the adrenal glands were small and contained many micronodules composed of large cells with brown or black pigment. Ten cases with similar pathology have been reviewed. In each case plasma ACTH was low when measured and urinary corticoid excretion did not decrease in response to dexamethasone administration. The difficulty in appreciating the presence of Cushing's syndrome clinically in these patients suggests that appropriate screening tests for Cushing's syndrome should be performed in patients with osteopenia of unknown etiology. The clexamethasone suppression test and measurement of urinary free cortisol excretion are recommended.