The role of preemptive antimicrobial therapy in kidney recipients of urine-only positive donor cultures.

Background: The use of preemptive antimicrobial therapy for recipients of donors with microbial growth on pre-transplant urine cultures remains poorly studied.

Methods: Single-center retrospective study of kidney transplant recipients of allografts from deceased donors with urine-only (ie, in absence of donor bacteremia) positive cultures (September 2011 to August 2015). Transplant outcomes, including donor-derived infections (DDI) within the first three months post transplant, were analyzed.

Results: Of the 970 kidney transplants performed during the study period, urine cultures were obtained from all donors, and of these, 27 (2.8%) yielded growth. Twenty-nine (73%) recipients were treated preemptively after transplantation. All of the recipients of donors with urine cultures positive for Enterococcus, Pseudomonas, or Candida spp. received therapy whereas only one of seven recipients with urine cultures positive for Escherichia coli was treated (P < .0001). All E coli isolates were susceptible to trimethoprim-sulfamethoxazole (TMP-SMX), which was given to all patients for Pneumocystis pneumonia (PCP) prophylaxis. Infection within 3 months was evident in 16 (40%) patients: 10 out of 29 (35%) in the preemptive group and 6 out of 11 (55%) in the not-treatment group (P = .29). Evidence of DDI occurred in two recipients, one in each group. There were no differences in one-year graft and patient survival between groups.

Conclusion: Preemptive antibiotic therapy did not seem to impact transmission events and transplant outcomes in this small cohort. Low transmission rates might have been influenced by administration of PCP prophylaxis and universal preemptive therapy for positive donor urine cultures with virulent organisms. Larger studies are needed.