Transplant kidney biopsy for proteinuria with stable creatinine: Findings and outcomes
Sandesh Parajuli, Kurtis J. Swanson, James Alstott, Fahad Aziz, Neetika Garg, Weixiong Zhong, Arjang Djamali, Didier A. Mandelbrot
Abstract
INTRODUCTION: Little is known aboutbiopsy findings and outcomes when kidney transplant recipients (KTRs) undergo biopsy for isolated proteinuria with stable serum creatinine (SCr). METHODS: We analyzed all KTRs who underwent biopsy for isolated proteinuria with stable SCr between January 2016 and June 2020. Patients were divided into three groups based on the biopsy findings: Active Rejection (AR), Glomerulonephritis (GN), and Other. RESULTS: A total of 130 KTRs fulfilled our selection criteria; 38 (29%) in the AR group, 26 (20%) in the GN group, and 66 (51%) in the Other group. Most baseline characteristics were similar between the groups. In multivariate analysis, higher HLA mismatch (HR per mismatch: 1.30; 95% CI:1.06-1.59; P = .01) and male gender (HR: .45; 95% CI .23-.89; P = .02) were associated with AR. There was no significant correlation between the degree of proteinuria and rejection (r = .05, P = .58) or GN (r = .07, P = .53). Graft survival was also similar between the groups. Likely due to the early diagnosis without a significant rise in SCr, outcomes were similar among all three groups. CONCLUSION: Routine monitoring for proteinuria followed by a biopsy and appropriate management may help to identify early acute graft injury and prevent graft failure.