Benefits of sulfamethoxazole-trimethoprim prophylaxis on rates of sepsis after kidney transplant

Background: The use of potent immunosuppression increases the risk of infectious complications following kidney transplantation. Sulfamethoxazole-trimethoprim (SMX/TMP) is an inexpensive broad-spectrum antimicrobial agent used in our center as lifelong prophylaxis against Pneumocystis jirovecii, unless contraindicated. This study evaluated the clinical impact of SMX/TMP prophylaxis compared with no prophylaxis with SMX/TMP (NoPPx), but with alternative agents. Methods: This was a retrospective cohort analysis of renal transplant recipients (RTR) transplanted from January 2002 through December 2010. Patients were divided into SMX/TMP group and NoPPX group, based on whether they received prophylaxis with SMX/TMP or not, and rates of sepsis were compared between groups. We also analyzed the pathogens and source implicated in these episodes, as well as the dose of SMX/TMP. Rates were compared using multivariate logistic regression. Results: With a mean follow-up of 4.8 (± 2.5) years, 63 cases of sepsis occurred in 1224 patients (5.1%), and 60% of these cases had a urinary source. The risk of sepsis was significantly reduced with prophylaxis vs. NoPPx (13.3% vs. 4.3% for SMX/TMP, P < 0.001), and this association was maintained through multivariate regression. Sepsis was associated with a numerically increased risk of graft loss and death that was not significantly affected by use of SMX/TMP. Conclusions: Prophylaxis with SMX/TMP is an inexpensive way to reduce the incidence of sepsis in RTR.