Molecular characterization of multidrug-resistant Klebsiella pneumoniae belonging to CC258 isolated from outpatients with urinary tract infection in Brazil

Abstract Objectives The present study aimed to characterize 48 Klebsiella pneumoniae isolated from outpatients with urinary tract infections (UTIs) in the micro-region of Ribeirao Preto, located in the Southeastern of Brazil. Methods Thee isolates were identified by conventional biochemical and phenotypic tests and confirmed as K. pneumoniae using MALDI-TOF VITEK ® MS. Antimicrobial susceptibility testing were performed by disk diffusion method as recommended by the Clinical Laboratory Standards Institute using thirty-eight different antibiotic discs. Fifteen β-lactamase and nine virulence encoding genes were investigated by PCR. The clonal relationships among the isolates were determined by Enterobacterial Repetitive Intergenic Consensus-PCR (ERIC-PCR) and Multilocus sequence typing (MLST). Results The results demonstrated that 29 isolates (60.4 %) were classified as multidrug-resistant (MDR). A total of 46 β-lactamase encoding genes were found in 27 isolates (56.3%) being bla KPC the most prevalent, distributed in 18 isolates (37.5 %). Moreover, 73 virulence genes were found in 34 of the 48 studied isolates (79.83 %). ERIC-PCR results showed a high genetic diversity among the isolates. Twelve different sequence types (STs) were found by MLST analysis (ST14, ST17, ST101, ST200, ST334, ST433, ST437, ST442, ST449, ST502, ST1246 and ST2729) being the ST2729 first described in this study. Seven STs were grouped in the CC258, frequently associated with various resistance and virulence genes. Conclusions These results raise a concern about epidemiological surveillance related to colonization of patients discharged from hospitals in order to prevent both occurrence and spread of resistant bacterial infections in the community.