Better recovery of kidney function in patients with de novo chronic kidney disease after partial nephrectomy compared with those with pre-existing chronic kidney disease

We compared kidney functional recovery between patients with pre-existing chronic kidney disease, those with de novo chronic kidney disease and those with normal kidney function, after partial nephrectomy. A total of 311 patients who underwent partial nephrectomy at Tokyo Women's Medical University Hospital, Tokyo, Japan, between January 2004 and July 2011 with sufficient kidney functional data participated in the study. Patients with pre-existing chronic kidney disease (group1: 78 patients) were defined as those with estimated glomerular filtration rate under 60 mL/min/m(2) before partial nephrectomy. Patients with de novo chronic kidney disease (group 2: 49) were defined as those with estimated glomerular filtration rate over 60 mL/min/m(2) before surgery and who developed estimated glomerular filtration rate under 60 mL/min/m(2) 3 months after partial nephrectomy. Normal patients (group 3: 184) were defined as those with estimated glomerular filtration rate over 60 mL/min/m(2) both before and after partial nephrectomy. Group 1 was associated with older age and higher comorbidity, including hypertension and diabetes mellitus, compared with other groups. R.E.N.A.L. score was not significantly different between the groups. Although the percent change of estimated glomerular filtration rate between the preoperative period and 3 months after partial nephrectomy in group 2 was significantly decreased compared with that in other groups (group 1: -6.8%, group 2: -18%, group 3: -7.3%), the renal functional recovery between 3 and 12 months after partial nephrectomy in group 2 was better than that in other groups (group 1: -0.5%, group 2: 5.6%, group 3: -0.4%). Patients with de novo chronic kidney disease had better kidney functional recovery than the other two groups, which might suggest that they were surgically assaulted and developed chronic kidney disease in the early postoperative period, and were essentially different from those with pre-existing chronic kidney disease.