Renal changes in primary aldosteronism.

The clinical presentations and renal biopsy specimens of 18 patients with primary aldosteronism were reviewed to determine the characteristic pathologic features of the kidney in this syndrome. All patients were hypertensive with a mean blood pressure of 192 nm. Hg systolic and 122 mm. Hg diastolic. The average duration of hypertension was 6.88 years. The mean serum potassium was 2.88 mEq. per l. and the mean plasma carbon dioxide was 31.4 mEq. per l. A significant history of urinary tract disease was noted in 8 patients. Laboratory and diagnostic studies evaluating renal structure and function were abnormal in 11 patients. Renal biopsies from all 18 individuals showed evidence of parenchymal damage. Hypertensive and hypokalemic changes were the most significant abnormalities and were considered moderate to severe in 78 and 89 per cent of the patients, respectively. Histologic evidence of pyelonephritis was noted in 2 patients only and no renal specimens contained characteristic changes of metabolic alkalosis. The preoperatively hypertensive and renal evaluations did not reflect the severity of the renal changes noted histologically. The extent of renal injury caused by hypertension and hypokalemia in these patients emphasizes the consequences of primary aldosteronism. Early diagnosis and treatment of this disorder are essential if these consequences are to be avoided.