The Benefits of a Well Functioning Allograft: Poorer Graft Function After Renal Transplantation Predisposes To Higher Rates of CMV Viremia.

Abstract

Objective The purpose of this study was to examine the effect of impaired post-transplant renal function on the development of CMV viremia. Methods We performed a retrospective chart review for all patients who received a kidney or SPK transplant since 2011 at our center. Patients were stratified into high and low functioning groups based on the median eGFR for the cohort (46 mL/min) at hospital discharge as calculated by the MDRD-4 equation. Results were analyzed using Kaplan-Meier product limit survival estimates to compute CMV-free survival over time. Results 177 patients received a kidney or SPK transplant between January 2011 and November 2013. 23 were excluded for a variety of reasons (not receiving valgancyclovir [13], primary non-function [2], pediatric transplants [3], or lost to follow-up [5]) and the remaining 154 patients were analyzed for the development of CMV viremia.Figure: No Caption available.The high functioning group had significantly lower rates of CMV viremia (9.0%) compared with the low functioning group (27.6%) at 1 year follow-up (p=0.0018), with a relative risk for CMV viremia of 2.25 (CI 1.17- 4.36) in the lower functioning group. The high functioning group did not have a statistically significantly different percentage (p=0.64) of high (D+/R-), intermediate (R+), and low (D-/R-) CMV risk patients (20.5%, 62.8%, and 16.7% respectively) to the low functioning group (18.6%, 69.3%, 12.0%). The low functioning group was on lower doses of valgancyclovir, but these were appropriate for their renal function. Conclusions Early graft dysfunction following renal transplantation carries a high risk for developing CMV viremia. It still remains to be determined whether it is the renal damage itself, or the reduction in valgancyclovir in response to lowered renal function which is the primary factor in this increased risk. In either scenario, patients with impaired renal function may warrant more aggressive CMV prophylaxis than previously thought.