Cause of residual hypertension after adrenalectomy in patients with primary aldosteronism.

The cause of residual hypertension after adrenalectomy for primary aldosteronism (PA) is unknown. The purpose of this study is to investigate the characteristic pathological kidney features associated with PA. Between 1977 and 1999 at our hospital, 26 patients with PA caused by a unilateral adrenal cortical adenoma (Conn's syndrome) underwent unilateral adrenalectomy with concurrent open-wedge renal biopsy. Patients were categorized into two groups: (1) those with normotension with diastolic blood pressure less than 90 mm Hg who were not administered antihypertensive drugs, and (2) those with residual hypertension with diastolic blood pressure of 90 mm Hg or greater who were administered medication for 6 months after surgery. Thirteen patients were cured of hypertension postoperatively, and 12 patients were administered antihypertensive medications. Glomerulosclerosis, renal arteriolosclerosis, and preoperative left ventricular mass (LVM) index were worse in the group with residual hypertension than in that with normotension (17.8% +/- 7.8% versus 9.6% +/- 3.8%; P = 0.01; 2.5 +/- 0.5 versus 1.6 +/- 0.4, Bader's grade; P = 0.005; and 165 +/- 31 versus 139 +/- 24 g/m(2); P = 0.02, respectively). Severity of tubulointerstitial injury, preoperative duration of hypertension, preoperative severity of proteinuria, plasma aldosterone level, and serum potassium concentration were not significantly different between the two groups. In conclusion, severity of glomerulosclerosis and arteriolosclerosis and LVM are related to blood pressure after adrenalectomy in patients with PA.