Urinary Tract Infections in Kidney Transplants. Risk Factors and Association of Klebsiella pneumoniae with Immediate Infections

CALZA Y.; BADARACCO ELVIRA; DI CONZA JOSÉ; AGUERRE A; BANGHER M; MAURICH S; GUTKIND GABRIEL; PEÑA LAURA

Washington

Conferencia; 54th ICAAC - Annual Interscience Conference on Antimicrobial Agents and Chemotherapy; 2014

American Society of Microbiology

Background: Urinary tract infections (UTI) are the most frequent complication in kidney transplants. Our main objectives were to evaluate the relative impact of several risk factors, the association of different enterobacteria with the time of infection onset, and resistance within each microorganism. Materials and methods: Transplant recipients (125 males/86 females) were strictly followed for one year for their first episode. Classical risk factors analysis was carried out (using SPSS v21 software). UTI were considered immediate if documented within 30 days, early (30 to 180 days), and late onset (181 to 365 days after transplant). Antimicrobial susceptibility was performed accordingly to current CLSI recommendations. Clonal relatedness (ERIC- PCR), phylogenetic groups and virulence genes (rmpA and magA) in hyper-mucoid K. pneumoniae, and ESBL genes were assessed by PCR. Results: 91/211 patients suffered an UTI: 49 were immediate, 25 early and 17 of late onset. Main risk factors for UTI were: urinary stent presence (n=40) OR, 2.32 (IC95%: 1.79-3.00); lithiasis (n=14), 2.13 (IC95%:1.63-2.81) and female gender (n=86), 1.48 (IC95%:1.13-1.94). Klebsiella pneumoniae accounted for 36 UTI, from them 27 were immediate, 6 early and 3 of late onset. All were resistant to SXT, 28 to CTX, 25 to CIP, 14 to NIT, 12 to TZP, 5 to AMK, 22 to GEN and 2 to ertapenem. Escherichia coli accounted for 30 UTI (10 immediate, 8 early and 12 of late onset). 24 were resistant to SXT, 10 to CIP, 2 to GEN and only 1 to NIT, CTX and AMK. Enterobacter cloacae accounted for 7 UTI (5 immediate, 2 of early onset). In a subset of 42 patients (represented by 75 UTI episodes from June 2012 to Nov, 2013), the four main E. coli phylogenetic groups were represented (11 A, 7 B1, 8 B2 and 9 D); no virulence genes were detected in 17/40 hypermucoid K. pneumoniae; 28/40 were ESBL producers (27 CTX-M-1 and 1 CTX-M-2 groups). CTX-M-2 group was associated with E. coli and CTX-M-1 group with K. pneumoniae. E. coli accounted for 4 recurrent and 2/22 patients re-infections, while K. pneumoniae for 9/20 patients recurrences. Conclusions: Immediate onset UTIs can be considered hospital-acquired infections caused by typical nosocomial pathogens. Once the main risk factors are defined, there is an opportunity for successful interventions on those patients at higher risk.