D Hammoudi1, C Ayoub Moubareck2, N Hakime3, M Houmani4, A Barakat5, Z Najjar6, M Suleiman7, N Fayad8, R Sarraf9, D Karam Sarkis10. 1. Microbiology Laboratory, School of Pharmacy, Saint-Joseph University, Campus of Medical Sciences, Damascus Road, PO Box 11-5076 Riad El Solh, Beirut 1107-2180, Lebanon; Rodolphe Mérieux Laboratory, Beirut, Lebanon; Department of Pharmaceutical Sciences, School of Pharmacy, Lebanese International University, Bekaa, Lebanon. Electronic address: dalal.hammoudi@net.usj.edu.lb. 2. Microbiology Laboratory, School of Pharmacy, Saint-Joseph University, Campus of Medical Sciences, Damascus Road, PO Box 11-5076 Riad El Solh, Beirut 1107-2180, Lebanon; Rodolphe Mérieux Laboratory, Beirut, Lebanon; Department of Natural Science and Public Health, College of Sustainability Sciences and Humanities, Zayed University, Dubai, United Arab Emirates. 3. Saint George Hospital and University of Balamand, Beirut, Lebanon. 4. Labib Medical Center, Saida, South Lebanon. 5. Bellevue Medical Center, Beirut, Lebanon. 6. Chtaura Hospital, Bekaa, Lebanon. 7. Farhat Hospital, Bekaa, Lebanon. 8. Secours Populaire Libanais Hospital, Nabatieh, South Lebanon. 9. Mounla Hospital, Tripoli, North Lebanon. 10. Microbiology Laboratory, School of Pharmacy, Saint-Joseph University, Campus of Medical Sciences, Damascus Road, PO Box 11-5076 Riad El Solh, Beirut 1107-2180, Lebanon; Rodolphe Mérieux Laboratory, Beirut, Lebanon.
Abstract
OBJECTIVES: The acquisition of carbapenemases by Acinetobacter baumannii is reported increasingly worldwide, but data from Lebanon are limited. The aims of this study were to evaluate the prevalence of imipenem-resistant A. baumannii in Lebanon, identify resistance determinants, and detect clonal relatedness. METHODS: Imipenem-resistant A. baumannii were collected from nine Lebanese hospitals during 2012. Antimicrobial susceptibility, the cloxacillin effect, and ethylenediaminetetraacetic acid (EDTA) synergy were determined. Genes encoding carbapenemases and insertion sequence ISAba1 were screened via PCR sequencing. ISAba1 position relative to genes encoding Acinetobacter-derived cephalosporinases (ADCs) and OXA-23 was studied by PCR mapping. Clonal linkage was examined by enterobacterial repetitive intergenic consensus PCR (ERIC-PCR). RESULTS: Out of 724 A. baumannii isolated in 2012, 638 (88%) were imipenem-resistant. Of these, 142 were analyzed. Clavulanic acid-imipenem synergy suggested carbapenem-hydrolyzing extended-spectrum β-lactamase. A positive cloxacillin test indicated ADCs, while EDTA detection strips were negative. Genotyping indicated that 90% of isolates co-harbored blaOXA-23 and blaGES-11. The remaining strains had blaOXA-23, blaOXA-24, blaGES-11, or blaOXA-24 with blaGES-11. ISAba1 was located upstream of blaADC and blaOXA-23 in 97% and 100% of isolates, respectively. ERIC-PCR fingerprinting revealed 18 pulsotypes spread via horizontal gene transfer and clonal dissemination. CONCLUSION: This survey established baseline evidence of OXA-23 and GES-11-producing A. baumannii in Lebanon, indicating the need for further surveillance.
OBJECTIVES: The acquisition of carbapenemases by Acinetobacter baumannii is reported increasingly worldwide, but data from Lebanon are limited. The aims of this study were to evaluate the prevalence of imipenem-resistant A. baumannii in Lebanon, identify resistance determinants, and detect clonal relatedness. METHODS:Imipenem-resistant A. baumannii were collected from nine Lebanese hospitals during 2012. Antimicrobial susceptibility, the cloxacillin effect, and ethylenediaminetetraacetic acid (EDTA) synergy were determined. Genes encoding carbapenemases and insertion sequence ISAba1 were screened via PCR sequencing. ISAba1 position relative to genes encoding Acinetobacter-derived cephalosporinases (ADCs) and OXA-23 was studied by PCR mapping. Clonal linkage was examined by enterobacterial repetitive intergenic consensus PCR (ERIC-PCR). RESULTS: Out of 724 A. baumannii isolated in 2012, 638 (88%) were imipenem-resistant. Of these, 142 were analyzed. Clavulanic acid-imipenem synergy suggested carbapenem-hydrolyzing extended-spectrum β-lactamase. A positive cloxacillin test indicated ADCs, while EDTA detection strips were negative. Genotyping indicated that 90% of isolates co-harbored blaOXA-23 and blaGES-11. The remaining strains had blaOXA-23, blaOXA-24, blaGES-11, or blaOXA-24 with blaGES-11. ISAba1 was located upstream of blaADC and blaOXA-23 in 97% and 100% of isolates, respectively. ERIC-PCR fingerprinting revealed 18 pulsotypes spread via horizontal gene transfer and clonal dissemination. CONCLUSION: This survey established baseline evidence of OXA-23 and GES-11-producing A. baumannii in Lebanon, indicating the need for further surveillance.
Authors: Micheline A H Soudeiha; Elias A Dahdouh; Eid Azar; Dolla K Sarkis; Ziad Daoud Journal: Front Cell Infect Microbiol Date: 2017-05-24 Impact factor: 5.293