Association of Bacteriuria by Time and Organism Following Kidney Transplantation with Allograft Survival and Rejection Open Access

Bacteriuria is a common complication after kidney transplantation (KT) and has been linked to poor allograft outcomes. While conflicting data exists regarding the association between bacteriuria and graft survival, little is known about the relative impact of specific organisms on graft survival and biopsy-proven acute rejection (BPAR).

We performed a single-center retrospective cohort study to analyze 1-year graft survival and BPAR rates by time to bacteriuria post-KT and by the 6 most common organisms, among 1,726 KT recipients from 2007–2015. A subcohort of 77 KTs whose first BPAR episode preceded first detected bacteriuria by more than 3 days was censored for the BPAR analyses.

KT recipients were 62% male, 52% from living donors, with a median age of 53 years. Bacteriuria rates were 8%, 19%, 26%, 29%, and 32% within 7, 30, 90, 180, and 365 days of KT, respectively. Death-censored 1-year graft survival did not significantly differ for KTs with any bacteriuria (96% vs. 97%, odds ratio [OR] 0.76, 95% confidence interval [CI] 0.43–1.36, P = 0.36), by time to bacteriuria post-KT (within 7, 30, 90, or 180 days) or by organism (Eschirichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Enterococcus faecium, Pseudomonas aeruginosa, or Enterobacter cloacae). BPAR rates were significantly higher for KTs with bacteriuria within 7, 30, and 90 days (31% vs. 22%, OR 1.65, CI 1.12 – 2.43, P = 0.01; 27% vs. 21%, OR 1.35, CI 1.02 – 1.79, P = 0.04; 26% vs. 21%, OR 1.32, CI 1.02 – 1.72, P = 0.04, respectively), but not for those with bacteriuria within 180 and 365 days (24% vs. 22%, OR 1.18, CI 0.91 - 1.52, P = 0.22; 24% vs. 22%, OR 1.11, CI 0.86 – 1.43, P = 0.41). BPAR rates were 23% for 209 KTs with E. coli, 20% for 138 KTs with E. faecalis, 17% for 109 KTs with K. pneumoniae, 27% for 71 KTs with E. faecium, 36% for 28 KTs with P. aeruginosa, and 42% for 26 KTs with E. cloacae. Only E. cloacae showed a significantly elevated BPAR rate (OR 2.64, CI 1.20–5.83, P = 0.02).

Death-censored graft survival was not significantly impacted by bacteriuria, regardless of time post-KT or organism. Early bacteriuria and E. cloacae were independently associated with an increased risk of BPAR. Further studies are warranted to examine this association for development of appropriate treatment practices.

All authors: No reported disclosures.