Clonal complexes 104, 109 and 113 playing a major role in the dissemination of OXA-carbapenemase-producing Acinetobacter baumannii in Southeast Brazil

• DOI: 10.1016/j.meegid.2013.06.024
• Publication Date: 2013-07-06T12:18:40Z
• Authors: Eduardo Carneiro ...; Milena Locci de O...; André Pitondo-Silva; Murilo Gomes Oliv...; Micheli Medeiros; Nilton Lincopan; Ana Lúcia da Cost...
• Keywords: Acinetobacter baumannii

Carbapenem resistance among Acinetobacter baumannii strains isolated from clinical settings in Brazil has increased dramatically the last 10 years due to emergence and dissemination of OXA-type carbapenemase encoding genes. This study aimed characterize presence carbapenem-hydrolyzing class D β-lactamases (CHDL)-encoding genes clonal complexes playing a major role OXA-carbapenemase-producing A. Southeast Brazil. A total 74 patients admitted 4 hospitals were analyzed. Molecular characterization revealed that 67 carried blaOXA-23 (72%), blaOXA-143 (25%) or both (3%). PFGE analysis identified 12 clusters, grouping 26 pulsotypes. Two clusters predominant, comprising more than 66% OXA-producing isolates. Among 23 representative characterized by MLST-UO (Multilocus Sequence Typing Scheme – University Oxford, http://pubmlst.org/abaumannii/), 14 different STs identified, which six confirmed as novel sequence types (designated 402–407). Most these isolates belonged CC104,CC109 CC113, whereas three singletons (ST339, 403 407). In conclusion, blaOXA-23- blaOXA-143-like was not related specific ST/CC, suggesting OXA-carbapenemase-encoding may involve STs, spread OXA-23-like is most likely mobile elements (i.e., plasmids). this regard, CC104, CC109 CC113 played predominant CDHL-carrying clones, instead CC92, identified.