A Clinical Observation on Twelve Cases of Primary Aldosteronism

Background: Primary aldosteronism describes a group of disorders characterized by long-standing aldosterone excess, with suppressed renin activity, resulting in hypertension and hypokalemia. The protean clinical and biochemical characteristics of this syndrome have important implications regarding its pathophysiology and responsiveness to treatment. Methods: The cases of 12 primary aldosteronisms, diagnosed at Hanyang University Hospital between 1996 and 1999, were reviewed. Results: The 12 cases were composed of 9 aldosterone-producing adenoma, 2 adrenal hyperplasia and a case of idiopathic hyperaldosteronism. There were 9 women and 3 men. The mean age was 46 yrs (range, 23 to 64 yrs). At the initial visit, the mean blood pressure was 160F26/104t14 mmHg, and one case of idiopathic hyperplasia had normal blood pressure. The mean serum K+ level was 2.60.5 mEq/L (range, 1.5 to 3.5 mEq/L). The mean plasma renin activity and plasma aldosterone concentration were 0.40.4 ng/ml/hr (range, 0.2 to 1.6 ng/ml/hr) and 407.5199.8 pg/mL (range, 225 to 800 pg/mL), respectively. Different steps of diagnostic modalities were applied for the preoperative differential diagnosis. All patients, with the exception of the one with idiopathic hyperaldosteronism, were managed by a unilateral laparoscopic adrenalectomy, as they were all diagnosed under the impression of adrenal adenomas. Ultimately, 9 cases were proven to have adrenal adenomas. One hypertensive case, with hypokalemia, had adrenal hyperplasia, and the case with normotension was found to have adrenal nodular hyperplasia from the pathology. The size of the tumors ranged from 1.4 to 2.4 cm in diameter. Among the 11 cases that underwent an adrenalectomy, the blood pressures in 6 cases normalized after the operation, while the other 5, including the one with unilateral hyperplasia, were still in need of antihypertensives for the control of elevated blood pressures, even after the operation. The other case of idiopathic hyperaldosteronism was managed by the prescription of spironolactone. Conclusion: From these, it can be suggested that the clinical diversity of the syndrome, especially in the pathophysiology and response to operation, awaits the development of a better preoperative lateralization procedure.