Back
Urinary tract infections (UTI) are the most frequent infection in kidney transplant (KT) patients. The objectives of the study were: to determine the clinical and microbiological characteristics of UTIs that occur during the first year after KT, to evaluate whether there was a change in the incidence of extended-spectrum beta-lactamase (ESBL)-producing microorganisms between two time periods and to analyze possible risk factors for the development of UTI due to multidrug-resistant microorganisms (MRM).
Retrospective cohort study that included patients over 18 years of age who received KT between 2009-2020 in two hospitals in Córdoba city, Argentina. Patients were followed up during the first year after the transplant by recording them in the medical records, and those who presented at least one episode of UTI were analyzed.
During the study period, 568 KTs were performed, of which 207 (36.4%) had at least one episode of UTI. Of them, 53.1% were women, with a median age of 53 (IQR 40-65) years. In total, there were 419 UTI episodes, 6 (1.4%) polymicrobial UTI episodes, so a total of 426 microorganisms were identified in the urine cultures. Of the total number of episodes, 206 (49.2%) occurred between 31 and 180 days post-transplant. The main etiological agent was E. coli with 225 isolates (52.8%) followed by Klebsiella sp. with 94 (22.1%). 52.1% of all episodes were caused by multi-resistant microorganisms (MRM). Among the E. coli isolates, 94 (41.8%) were MRM. When comparing the proportion of isolations of ESBL-producing microorganisms between 2 periods, we have observed a higher proportion in the period 2016-2020 compared to 2009-2015 (53.7% -130/242 UTI- vs. 29.5% -51/173 UTI, p<0.01). Likewise, the number of ESBL-producing E. coli isolates was higher in the second period (47.2% -58/123 UTI- vs. 20.8% -20/96 UTI, p<0.01) (Figure 1). The main risk factor associated with UTI due to MRM was a history of recurrent UTIs (RR=1.62; 95%CI=1.29-2.02; p<0.001) and the only protective factor was the use of basiliximab as induction (RR=0.78; 95%CI=0.64-0.94; p=0.012).
UTIs occurred in more than a third of kidney transplant patients during the first-year post-transplant, and just over half were caused by MRM. There was an increase in the incidence of ESBL-producing microorganisms.