Urinary tract infections during the first year after renal transplantation: one center's experience and a review of the literature.

Background: The aim of the study was to evaluate the incidence, clinical manifestations, microbiology, risk factors, and the influence of UTIs on renal graft function.

Methods: We analyzed clinical data, urine cultures performed within the first 12 months after RTx, and renal function within 24 months in consecutive patients undergoing RTx at Gdańsk Transplantation Centre between January 2007 and December 2009.

Results: We studied data from 209 RTx recipients, 59.3% men, with a mean age of 46.4 ± 14 yr. We observed 322 UTI episodes in 111 patients, including asymptomatic bacteriuria (53%, n = 170), lower UTIs (25%, n = 82), upper UTIs (22%, n = 57), and 13 cases of urosepsis. Thirty-eight percent of UTIs were diagnosed during the first post-transplant month. The most frequently isolated uropathogen was Enterococcus faecium (36%, n = 44) and from the second month E. coli (58%, n = 114). Risk factors were female gender, induction use, history of recurrent UTIs before RTx, acute rejection (AR), CMV infection, vesico-ureteral reflux or strictures at uretero-vesical junction, and high comorbidity. Renal graft function measured by eGFR was significantly worse in patients suffering from UTIs from the baseline. However, the evolution of renal graft function did not differ significantly between patients with and without UTIs.

Conclusions: Lower renal graft function may promote UTIs or UTIs may not allow a complete recovery of graft function after transplantation.