Long-term Change of Renal Function after Donor Nephrectomy for Kidney Transplantation / 대한이식학회지

ABSTRACT

PURPOSE: Occurrence of renal failure and its related complications such as hypertension are long-term problems after donor nephrectomy for living donor kidney transplantation. We retrospectively reviewed renal function of unilateral kidney donor. METHODS: From 669 living donors for kidney transplantation from December 1998 to October 2006, laboratory data related to renal function are collected from hospital medical record retrospectively in 251 (37.5%) donors who were followed-up after discharge. The selection criteria of donors were 1) pre-nephrectomy serum creatinine level below 1.5 mg/dL, 2) no radiologic abnormality in bilateral kidney. The donor nephrectomy was performed by conventional open nephrectomy or video assisted minilaparotomy surgery. The estimated glomerular filtration rate (e-GFR) by Modification of Diet in Renal Disease (MDRD) study was used as renal function monitoring parameter. RESULTS: In immediate post-nephrectomy period, e-GFR was decreased to 67.8+/-4.6% of pre-nephrectomy level (93.8+/-9.9 mL/min/1.73 m2). The urinary protein excretion for 24 hours was increased to 255% of pre-nephrectomy level (76.4+/-4.6 mg/day), but cases with proteinuria more than 300 mg per day were only 4 cases (1.7%, 4/251). After 14.0+/-5.2 months follow-up (range 1~80 months), two cases (0.8%, 2/251) of renal failure (chronic kidney disease stage 5) were found. Relative renal function (post-nephrectomy e-GFR ratio versus pre-nephrectomy e-GFR, %) was increased by post-nephrectomy duration. The mean scores of e-GFR ratio within post-nephrectomy 2 months, 3~11 months, 12~23 months and after 24 months were 64.8+/-10.4%, 66.4+/-9.7%, 69.5+/-10.9% and 75.8+/-17.6% respectively. The relative e-GFR ratio after 24 months was significantly different from those of within 24 months (P<0.0001 by ANOVA). In linear regression analysis, mean increment of e-GFR ratio per post-nephrectomy year was 2.88%. CONCLUSION: In spite of possibility of renal failure, our study shows the long-term compensation of residual renal function after nephrectomy.