Impact of urinary tract infections on short-term kidney graft outcome.

Urinary tract infections (UTIs) are frequent after renal transplantation, but their impact on short-term graft outcome is not well established. All kidney transplants performed between July 2003 and December 2010 were investigated to evaluate the impact of UTI on graft function at 1 year after transplantation. Of 867 patients who received a kidney transplant, 184 (21%) developed at least one episode of UTI, at a median of 18 days after transplantation. The prevalence of acute graft pyelonephritis (AGP) was 15%. The most frequent pathogens identified were Escherichia coli, Klebsiella species, and Pseudomonas aeruginosa, 37% of which were considered to be multidrug-resistant strains. Thirty-eight patients (4%) lost their grafts, 225 patients (26%) had graft function impairment and the 1-year mortality rate was 3%; however, no patient died as a consequence of a UTI. Surgical re-intervention and the development of at least one episode of AGP were independently associated with 1-year graft function impairment. Moreover, the development of at least one episode of AGP was associated with graft loss at 1 year. Patients with AGP caused by a resistant strain had graft function impairment more frequently, although this difference did not reach statistical significance (53% vs. 36%, p 0.07). Neither asymptomatic bacteriuria nor acute uncomplicated UTI were associated with graft function impairment in multivariate analysis. To conclude, UTIs are frequent in kidney transplant recipients, especially in the early post-transplantation period. Although AGP was significantly associated with kidney graft function impairment and 1-year post-transplantation graft loss, lower UTIs did not affect graft function.

Impact of antibiotic resistance on the development of recurrent and relapsing symptomatic urinary tract infection in kidney recipients.

We sought to determine the frequency, risk factors, and clinical impact of recurrent urinary tract infections (UTI) in kidney transplant recipients. Of 867 patients who received a kidney transplant between 2003 and 2010, 174 (20%) presented at least one episode of UTI. Fifty-five patients presented a recurrent UTI (32%) and 78% of them could be also considered relapsing episodes. Recurrent UTI was caused by extended-spectrum betalactamase (ESBL)-producing Klebsiella pneumoniae (31%), followed by non-ESBL producing Escherichia coli (15%), multidrug-resistant (MDR) Pseudomonas aeruginosa (14%), and ESBL-producing E. coli (13%). The variables associated with a higher risk of recurrent UTI were a first or second episode of infection by MDR bacteria (OR 12; 95%CI 528), age >60 years (OR 2.2; 95%CI 1.15.1), and reoperation (OR 3; 95%CI 1.37.1). In addition, more relapses were recorded in patients with UTI caused by MDR organisms than in those with susceptible microorganisms. There were no differences in acute rejection, graft function, graft loss or 1 year mortality between groups. In conclusion, recurrent UTI is frequent among kidney recipients and associated with MDR organism. Classic risk factors for UTI (female gender and diabetes) are absent in kidney recipients, thus highlighting the relevance of uropathogens in this population.