The dilemma of bilateral adrenocortical nodularity in Conn's and Cushing's syndromes.

Bilateral adrenal nodularity in Conn's and Cushing's syndrome leads to a more complex differential diagnosis than the presence of a unilateral mass or bilateral hyperplasia. In Conn's syndrome, bilateral nodularity is not synonymous with hyperplasia, and adrenal venous sampling is required to detect those cases of surgically correctable aldosteronoma. In Cushing's syndrome, bilateral nodularity can result from an ACTH-dependent or an autonomous adrenal cause of hypercortisolemia. The appropriate therapeutic decisions depend on the recognition of these different entities.