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bioRxiv · 10.1101/2024.11.28.625853

An investigation of carbapenemase-encoding genes in Burkholderia cepacia and Aeromonas sobria nosocomial infections among Iraqi patients

Al-Ouqaili, M. T. S.·Hussein, R. A.·Kanaan, B. A.·Al-Neda, A. T.
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Abstract

Burkholderia cepacia and Aeromonas sobria are difficult to eradicate due to their innate resistance to a variety of medications, and cause various diseases. The aim of this study was to investigate the occurrence of carbapenemase genes and patterns of antibiotic resistance in isolates of B. cepacia and A. sobria. A cross-sectional study was conducted in the Ramadi Teaching Hospitals in the Al-Anbar Governorate in 2024. Various study samples, were used to collect the studied bacteria. The antibiotic resistance was detected by the VITEK(R)2 System. The presence of carbapenemase genes was confirmed via PCR technique. In this investigation, seventy-five (75) isolates of A. sobria and B. cepacia were assessed. Of these, A. sobria made up 16.6% (n = 20) while B. cepacia accounted for 45.8% (n = 55). The study isolates showed highest antimicrobial resistance to piperacillin, cefepime, ceftriaxone (100%), ceftazidime (97.3%), and lowest antimicrobial resistance to imipenem (36%). The result showed 55/57 recA gene positive for differentiated B. cepacia complex from other Burkholderia spp. The overall prevalence of carbapenemase genes was 92.8%% (52/56) with blaKPCaccounting for 80.8% (42/52) and blaGES for 19.2% (10/52) of the total. The 42 B. cepacia isolates that tested positive for carbapenem resistance were constituted of 38 blaKPC (n = 38) and two blaGES (n = 2); in contrast, four blaKPC(n = 4) and eight blaGES (n = 8) were present in the A. sobria isolates that tested positive for carbapenems resistance. None of isolates studied tested positive for the blaIMPgene. The recent study concluded that recA gene identification was more sensitive and specific technique for detection B. cepacia complex isolates. There was a notable predominance of blaKPC and blaGEScarbapenemase producers among the isolates under investigation. The blaIMPgene was not found in any of the research isolates.

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Al-Ouqaili, M. T. S., Hussein, R. A., Kanaan, B. A., Al-Neda, A. T.. 2024-11-29. An investigation of carbapenemase-encoding genes in Burkholderia cepacia and Aeromonas sobria nosocomial infections among Iraqi patients. https://doi.org/10.1101/2024.11.28.625853

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