Here is a 1.3 cm left adrenal adenoma found in a patient with hypertension. She had hypokalemia on a routine chemistry panel. Further workup revealed a high serum aldosterone and a low serum renin, findings consistent with an aldosterone secreting adrenal adenoma (Conn's syndrome). This lesion accounts for about two-thirds of cases of primary hyperaldosteronism (PHA), while bilateral adrenal hyperplasia accounts for about 30% of PHA. Such adenomas are typically less than 2 cm in size and yellow on cut surface.