Antibiotic Sensitivity and Resistance Among the Most Common Uropathogens in Kidney Transplant Recipients

Abstract Introduction. Urinary tract infection (UTI) among kidney transplant recipients (KTRs) is one of the most common complications after transplantation. The aim of our study was to analyze the antibiotic sensitivity and resistance of the most common agents causing UTI in Bulgarian KTRs followed up in our Transplant Center. Methods. We analyzed the antibiotic resistance and sensitivity of the most common strains of bacteria causing UTI in the Bulgarian KTRs, namely class Enterobac-teriaceae and Enterococcus spp. We used conventional biochemical methods to identify different strains of uro-pathogens-miniApi (bioMerieux, France) and BBL Crystal (BD). The antibiotic sensitivity was determined via disc-diffusing method, according to the accepted Bulgarian CLSI standard. We used WHONET, version 5.6 to analyze the antibiotic resistance data. Results. The total number of tested patients was 366 [males 228, females 138]. The total number of tested urine samples was 829 [positive ones-203), negative samples 606, contaminated 20]. The most commonly detected uropathogens in Bulgarian KTRs were Gram /-/ negative bacteria (63.80%). Of these, 93.28% belonged to the Enterobacteriaceae group, with E. coli, K. pneumoniae and the PPM /Proteus, Providentia, Mor-ganela/subgroup being the most common (54.5%, 19.20% and 16%, respectively). Gram /+/ positive bacteria were detected in 28.09% of the patients, Enterococcus spp being the most commonly isola-ted-67.79%. In the Enterococcus group, the strains of E. faecalis and E. faecium were the most commonly detected. The bacteria belonging to Enterobacteriaceae group were most sensitive to carbapenems and aminoglycosides, with sensitivity peaking to almost 100%, whereas they were least sensitive to aminopenicillines [sensitivity below 20%]. The PPM subgroup revealed very high sensitivity to beta-lactamase protected broad spectrum penicillins (Piperacillin/Tazobactam, sensitivity - 90%). Gram /+/ positive uropathogens were mostly sensitive to Linezolid, Vancomycin, Teicoplanin (100%). These strains were least sensitive to Erythromycin and Tetracicline (17.50%). Conclusions. Our results were similar to previous studies. The differences detected can be explained with the characteristics of the bacterial strains and the specific practice of each transplant center. Having in mind the possible complications of UTIs, further studies are needed to clarify the problem with antimicrobial resistance in uropathogens and the use of antibiotics after KT.