First report of New Clonal groups ST706 and ST1088 from MDR Klebsiella pneumoniae Mexican strains

Abstract

Multidrug-resistant Klebsiella pneumoniae Mexican strains were characterized for the identification of endemic and pandemic clonal groups. The aims of this study were to know population structure and to identify endemic clonal groups inside K. pneumoniae Mexican strains isolated from clinical sources. We studied 93 isolated strains from three third level hospitals and one family clinic from Mexico City. Identification of the strains was done by conventional microbiological methods and an automated system (Vitek2(R)). The multidrug-resistant phenotype was confirmed following CLSI recommendations, and the strains were classified as MDR, XDR and PDR. Molecular characterization was done by Multilocus Sequence Typing scheme (rpoB, gapA, mdh, pgi, phoE, infB, y tonB). All strains were isolated from hospitalized patients, the most frequent sources were urine and blood cultures. Population structure of K. pneumoniae was clonal, 30 ST were identified, six of them are commonly found. The Clonal complex ST25, ST36, S5392, ST405 and ST551 were isolated from clinical sources, ST1088 was isolated from surfaces of hospital environment.