A CASE OF ALDOSTERONE PRODUCING ADENOMA ASSOCIATED WITH HIGH PRA AFTER LONG-TERM ANGIOTENSIN-CONVERTING ENZYME-INHIBITOR TREATMENT

A 62-year-old patient with non-insulin dependent diabetes (NIDDM) was admitted to our hospital for blood pressure control. He had been treat ed with angiotensin converting enzyme inhibitor (ACEI) for 7 years and showed marked hypokalemia with increased urinary potassium excretion. Hormonal examination revealed a normal plasma aldosterone concentrati on and increased plasma renin activity (PRA, 13.4 ng/ml/h), so potassi um losing nephropathy was suspected. After discontinuation of the ACEI , PRA decreased to normal. An adrenal adenoma was found on abdominal m agnetic resonance imaging (MRI) and adrenalectomy was performed to con firm aldosterone producing adenoma (APA). Although ACEIs are said not to alter PRA in APA, this drug was primarily responsible for the incre ased PRA in this case. This is a rare case of APA, which showed marked ly increased PRA during ACEI treatment.