BACKGROUND: The emergence of carbapenem-resistant Acinetobacter baumannii (CRAB) was observed in a Kenyan hospital from 2009 to 2010. Further investigation of the dissemination of CRAB isolates and the molecular characterization of associated resistance determinants were therefore performed. METHODS: Antibiotic susceptibilities were determined by broth microdilution and Etest. Metallo-β-lactamases were detected by Etest method. Clonal relationships were studied by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). β-Lactam and aminoglycoside resistance determinants and the clonal relatedness to widespread European clones were studied by PCR and sequencing. RESULTS: Sixteen CRAB isolates from 10 patients possessed six pulsotypes; half of the isolates belonged to the European clone II (ECII) lineage. ECII strains were typed as MLST sequence type 2 (ST2) and ST109, and non-ECII strains as ST25 and ST113. All isolates harbored ISAba1-blaOXA-23, blaOXA-51-like, blaADC, and class 1 integron, including one that also harbored blaNDM-1. ADC-57 and two integron cassettes (arr-2-cmlA5 and aadB-aadA2-cmlA6-aadA15) were newly-identified. Non-ECII isolates, designated non-ECII clone, carried armA and integron cassette arr-2-cmlA5. CONCLUSIONS: Two distinct clones of CRAB--ECII and non-ECII epidemic clones--were disseminated in Kenya. The concomitance of ISAba1-blaOXA-23 was the major mechanism contributing to CRAB. The first identification of ECII CRAB and New Delhi metallo-β-lactamase 1 (NDM-1) extensively drug-resistant A. baumannii in East Africa is of concern.
BACKGROUND: The emergence of carbapenem-resistant Acinetobacter baumannii (CRAB) was observed in a Kenyan hospital from 2009 to 2010. Further investigation of the dissemination of CRAB isolates and the molecular characterization of associated resistance determinants were therefore performed. METHODS: Antibiotic susceptibilities were determined by broth microdilution and Etest. Metallo-β-lactamases were detected by Etest method. Clonal relationships were studied by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). β-Lactam and aminoglycoside resistance determinants and the clonal relatedness to widespread European clones were studied by PCR and sequencing. RESULTS: Sixteen CRAB isolates from 10 patients possessed six pulsotypes; half of the isolates belonged to the European clone II (ECII) lineage. ECII strains were typed as MLST sequence type 2 (ST2) and ST109, and non-ECII strains as ST25 and ST113. All isolates harbored ISAba1-blaOXA-23, blaOXA-51-like, blaADC, and class 1 integron, including one that also harbored blaNDM-1. ADC-57 and two integron cassettes (arr-2-cmlA5 and aadB-aadA2-cmlA6-aadA15) were newly-identified. Non-ECII isolates, designated non-ECII clone, carried armA and integron cassette arr-2-cmlA5. CONCLUSIONS: Two distinct clones of CRAB--ECII and non-ECII epidemic clones--were disseminated in Kenya. The concomitance of ISAba1-blaOXA-23 was the major mechanism contributing to CRAB. The first identification of ECII CRAB and New Delhi metallo-β-lactamase 1 (NDM-1) extensively drug-resistant A. baumannii in East Africa is of concern.
Authors: Deja Rodgers; Fernando Pasteran; Manuel Calderon; Sara Jaber; German M Traglia; Ezequiel Albornoz; Alejandra Corso; Alejandro J Vila; Robert A Bonomo; Mark D Adams; María Soledad Ramírez Journal: J Glob Antimicrob Resist Date: 2020-09-02 Impact factor: 4.035
Authors: Nabil Karah; Ørjan Samuelsen; Raffaele Zarrilli; Jason W Sahl; Sun Nyunt Wai; Bernt Eric Uhlin Journal: PLoS One Date: 2015-02-23 Impact factor: 3.240