False localization of an aldosteronoma by dexamethasone-suppressed adrenal scintigraphy

A patient with primary aldosteronism had bilateral adrenal tumours on computed tomography. Selenocholesterol scintigraphy showed uptake by the larger right adrenal gland and a tumour in the gland was also visualized by venography. In contrast, measurements of aldosterone concentrations in adrenal venous blood lateralized to the left side. At surgery the left adrenal gland contained an aldosteronoma and the right adrenal gland a large non-functioning adenoma. Thus, selenocholesterol scintigraphy incorrectly localized the functioning adrenal tumour.