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bioRxiv · 10.1101/2020.08.24.264911

Molecular Characterization of Carbapenem-Resistant Acinetobacter baumannii Clinical Isolates from Egyptian Patients

Hassan, R. M.·Salem, S. T.·Hassan, S. I. M.·Hegab, A. S.·Elkholy, Y. S.·Reem M Hassan, Sherifa T Salem, Saly Ismail Mostafa Hassan, Yasmine S Elkholy,
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Abstract

Acinetobacter baumannii (A. baumannii) represents a global threat owing to its ability to resist most of the currently available antimicrobial agents. Moreover, emergence of carbapenem resistant A. baumannii (CR-AB) isolates limits the available treatment options. Enzymatic degradation by variety of {beta}-lactamases, have been identified as the most common mechanism of carbapenem resistance in A. baumannii. The alarming increase in the prevalence of CR-AB necessitates continuous screening and molecular characterization to appreciate the problem. The present study was performed to assess the prevalence and characterize carbapenemases among 206 CR-AB isolated from various clinical specimens collected from different intensive care units at Kasr Al-Aini Hospital. All isolates were confirmed to be A. baumannii by detection of the blaOXA-51-like gene. Molecular screening of 13 common Ambler class bla carbapenemases genes in addition to insertion sequence (IS-1) upstream OXA-23 was performed by using four sets of multiplex PCR, followed by identification using gene sequencing technology. Among the investigated genes, the prevalence of blaOXA-23, and blaOXA-58 were 77.7%, and 1.9%, respectively. The ISAba1 was detected in 10% of the blaOXA-23 positive isolates. The prevalence of metallo-{beta}-lactamases (MBLs) studied; blaNDM-1, blaSPM, blaVIM, blaSIM-1 were 11.7%, 6.3%, 0.5%, and 0.5% respectively. One of class A; bla KPC was detected in 10.7% of the investigated isolates. blaOXA-24/40, blaIMP, blaGES, blaVEB and blaGIM were not detected in any of the studied isolates. Moreover, 18.4% of the isolates have shown to harbor two or more of the screened bla genes. We concluded that the most prevalent type of {beta}-lactamases genes among CR-AB isolates collected from Egyptian patients were blaOXA-23 followed by blaNDM-1 and blaKPC. Author summaryCarbapenem-resistant A. baumannii has become a real global health threat. The aim of the present study was to characterize and to assess the prevalence of carbapenemases among 206 CR-AB clinical isolates from Egyptian patients. We concluded that the most prevalent type of {beta}-lactamases genes among CR-AB isolates collected from Egyptian patients were blaOXA-23 followed by blaNDM-1 and blaKPC. In this study, ISAba1 was detected upstream 10% of blaOXA-23 positive isolates only which indicates that the spread of resistance among Acinetobacter isolates could be either chromosomal or plamid-mediated.

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Hassan, R. M., Salem, S. T., Hassan, S. I. M., Hegab, A. S., Elkholy, Y. S., Reem M Hassan, Sherifa T Salem, Saly Ismail Mostafa Hassan, Yasmine S Elkholy,. 2020-08-25. Molecular Characterization of Carbapenem-Resistant Acinetobacter baumannii Clinical Isolates from Egyptian Patients. https://doi.org/10.1101/2020.08.24.264911

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