Adaptive functional change of the contralateral kidney after partial nephrectomy
AJP - Renal Physiology
Partial nephrectomy aims to maintain renal function by nephron sparing; however, functional changes in the contralateral kidney remain unknown. We evaluate the functional change in the contralateral kidney using a diethylene triamine penta-acetic acid (DTPA) renal scan and determine factors predicting contralateral kidney function after partial nephrectomy. A total of 699 patients underwent partial nephrectomy, with a DTPA scan before and after surgery to assess the separate function of each
... function of each kidney. Patients were divided into three groups according to initial contralateral glomerular filtration rate (GFR; group 1: Ͻ30 ml·min Ϫ1 ·1.73 m Ϫ2 , group 2: 30 -45 ml·min Ϫ1 ·1.73 m Ϫ2 , and group 3: Ն45 ml·min Ϫ1 ·1.73 m Ϫ2 ). Multiple-regression analysis was used to identify the factors associated with increased GFR of the contralateral kidney over a 4-yr postoperative period. Patients in group 1 had a higher mean age and hypertension history, worse American Society of Anesthesiologists score, and larger tumor size than in the other two groups. The ipsilateral GFR changes at 4 yr after partial nephrectomy were Ϫ18.9, Ϫ3.6, and 3.9% in groups 1, 2, and 3, respectively, whereas the contralateral GFR changes were 10.8, 25.7, and 38.8%. Age [␤: Ϫ0.105, 95% confidence interval (CI): Ϫ0.213; Ϫ0.011, P Ͻ 0.05] and preoperative contralateral GFR (␤: Ϫ0.256, 95% CI: Ϫ0.332; Ϫ0.050, P Ͻ 0.01) were significant predictive factors for increased GFR of the contralateral kidney after 4 yr. The contralateral kidney compensated for the functional loss of the ipsilateral kidney. The increase of GFR in contralateral kidney is more prominent in younger patients with decreased contralateral renal function.