A Case of Aldosterone Producing Adenoma Associated with High PRA after Long-Term Angiotensin Converting Enzyme Inhibitor Treatment.

Abstract

Abstract. A 62-year-old patient with non-insulin dependent diabetes (NIDDM) was admitted to our hospital for blood pressure control. He had been treated 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 concentration and increased plasma renin activity (PRA, 13.4 ng/ml/h), so potassium losing nephropathy was suspected. After discontinuation of the ACEI, PRA decreased to normal. An adrenal adenoma was found on abdominal magnetic resonance imaging (MRI) and adrenalectomy was performed to confirm aldosterone producing adenoma (APA). Although ACEIs are said not to alter PRA in APA, this drug was primarily responsible for the increased PRA in this case. This is a rare case of APA, which showed markedly increased PRA during ACEI treatment. ALDOSTERONE producing adenoma (APA) is a subtype of primary aldosteronism. It usually manifests as hypertension, hypokalemia, suppressed plasma renin activity (PRA), and hyperaldosteronism. Captopril is one of the angiotensin converting enzyme inhibitors (ACEI), which inhibits conversion of angiotensin I to angiotensin II and aldosterone production in normal conditions. In the setting of APA, however, aldosterone secretion is autonomous and not responsive to angiotensin II, so ACEI has little effect on either aldosterone production or PRA [l, 2]. In this report, we describe a patient with APA who had a normal A 62-year-old man was admitted to our hospital for blood pressure control. He had a 35-yearhistory of hypertension and had been a noninsulin dependent diabetic (NIDDM) for 18 years. He had had a left cerebral hemorrhage at 38 years of age and a cerebral infarction at age 50, at which time his blood pressure was 1901130 mmHg. Medication for hypertension and diabetes had been prescribed by a clinic at his place of employment. At age 51, while he was hospitalized at another facility for hypertension and diabetes, a