LONG-TERM RENAL-FUNCTION AFTER UNILATERAL NEPHRECTOMY

The long-term impact of an uninephrectomy on renal function and on art erial pressure was analyzed retrospectively in 87 patients (57 +/- 1.1 [SEM] years) 10.7 +/- 0.61 years after the operation The renal parame ters measured were: creatinine clearance, proteinuria (total protein, albumin, IgG, alpha(1)-microglobulin, transferrin) and enzymuria (beta -NAG, LAP, and gamma-GT). Mean creatinine clearance was 90.2 +/- 2.3 m l/min/1.73 m(2) and proteinuria 30.1 +/- 6.49 mg/dl in all patients. H ypertension (greater than or equal to 140/95 mmHg) was present in 43 p atients (49.4%) and had newly developed since uninephrectomy in 24 of these patients (55.8%). Normofiltration (greater than or equal to 90% compared to age-matched two-kidney controls with normal renal function ) was present in 42 patients (48.8%) and hypofiltration (< 90%) in 45 patients (51.2%). Proteinuria was significantly greater in hypertensiv e (57.4 +/- 14.7 mg/dl) than in normotensive patients (16.1 +/- 2.2 mg /dl, p < 0.01). Urinary excretion of total protein, albumin, IgG, and transferrin as well as of gamma-GT and beta-NAG was significantly grea ter (p < 0.01) in hypertensive patients with hypofiltration than in th ose with normofiltration. Mean arterial pressure (109.6 +/- 1.6 mmHg) increased with decreasing creatinine clearance (n = 81, r = 0.29, p < 0.01), increasing proteinuria (n = 71, r = 0.34, p < 0.01) and albumin uria (n = 71, r = 0.32, p < 0.01). There were no significant relations hips between date of nephrectomy and incidence of arterial hypertensio n or time since nephrectomy and proteinuria. The results demonstrate t hat uninephrectomy has no significant impact on parameters of renal fu nction measured after 10 years as long as arterial pressure remains no rmal. Increased proteinuria and enzymuria with respect to the normal v alues of healthy two-kidney subjects as markers for renal damage were only present in hypertensive uninephrectomized patients. The risk for the development of arterial hypertension after uninephrectomy is not i ncreased compared to age matched normal subjects.