Mohamed Mefreh, Maysaa E S Zaki, Mona Abdelaltif, Mona A E-H A El-Raouf, Ahmed H El-Nagdy, Nadia G Elrefaei, Sara G Eissa
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引用次数: 0
Abstract
Background: Several factors play a role in the pathogenesis of Acinetobacter baumannii (A. baumannii). This study aimed to determine the virulence genes of A. baumannii isolated from healthcare-associated bacteremia (HAB) in pediatric patients, as well as their biofilm-forming ability and resistance to carbapenem antibiotics.
Methods: One hundred isolates of A. baumannii from healthcare-associated bacteremia in children, collected be-tween January 2024 and January 2025, were subjected to biochemical identification using the API 20NE system, and confirmation of A. baumannii was performed by PCR targeting the blaOXA-51-like gene. Biofilm formation determination was quantified using the standard microtiter plate assay with crystal violet staining. Antimicrobial susceptibility testing was conducted using the Kirby-Bauer disc diffusion method on Mueller-Hinton agar. Genetic studies using the polymerase chain reaction (PCR) were performed to detect virulence-associated genes, including bap, surA1, pld, csuE, ompA, kps, and iron acquisition genes (basD, entE, and tonB) [17-22]. Screening for carbapenemase genes (blaOXA-23, blaOXA-24/40, blaOXA-58, blaNDM) was also conducted.
Results: A. baumannii was able to form strong biofilm in 20%, intermediate biofilm in 30%, and weak biofilm in 25% of the isolates. All A. baumannii isolates contained the bap and surA1 genes (100%), the pld gene (84%), and the basD gene (79%).
Conclusions: The significant presence of bap and surA1 genes among all imipenem-resistant and biofilm-forming isolates highlights their central role in enhancing both virulence and antimicrobial resistance. Moreover, there are significant correlations between imipenem resistance, omp33-36, and blaOXA-40, emphasizing the combined contribution of altered membrane permeability and carbapenemase activity to resistance phenotypes. The association of biofilm formation with blaOXA-23 and basD genes further reflects a multifactorial resistance strategy.
期刊介绍：
Clinical Laboratory is an international fully peer-reviewed journal covering all aspects of laboratory medicine and transfusion medicine. In addition to transfusion medicine topics Clinical Laboratory represents submissions concerning tissue transplantation and hematopoietic, cellular and gene therapies. The journal publishes original articles, review articles, posters, short reports, case studies and letters to the editor dealing with 1) the scientific background, implementation and diagnostic significance of laboratory methods employed in hospitals, blood banks and physicians'' offices and with 2) scientific, administrative and clinical aspects of transfusion medicine and 3) in addition to transfusion medicine topics Clinical Laboratory represents submissions concerning tissue transplantation and hematopoietic, cellular and gene therapies.
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