Clonal relatedness of carbapenem-resistant Acinetobacter baumannii: high prevalence of ST136pas in a burn center

Annals of Clinical Microbiology and Antimicrobials

Research

Farzad Badmasti¹  Vajihe Sadat Nikbin¹  Mahnaz Nikibakhsh²  Farzaneh Firoozeh³  Mohammad Zibaei⁴ 

[1] Department of Bacteriology, Pasteur Institute of Iran, Tehran, Iran;Department of Microbiology, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran;Department of Microbiology, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran;Evidence-based Phytotherapy and Complementary Medicine Research Center, Alborz University of Medical Sciences, Karaj, Iran;Department of Parasitology and Mycology, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran;

关键词: A. baumannii;    bla;    amp;    Clonal complex;    Burn patient;   

DOI  :  10.1186/s12941-023-00589-9

 received in 2022-04-09, accepted in 2023-04-27,  发布年份 2023

来源: Springer

【 摘 要 】

BackgroundCarbapenem-resistant Acinetobacter baumannii (CRAB) is a global health crisis. This study aimed to determine the clonal relatedness of antibiotic-resistant A. baumannii isolates in hospitalized patients who suffered from burn wound infection.MethodsOne hundred and six A. baumannii isolates from 562 patients with burn wound infections, were identified and examined for antimicrobial susceptibility. Detection and characterization of carbapenem-hydrolyzing class D OXA-type beta-lactamases (CHDLs) were performed by PCR assays. The clonal relatedness of A. baumannii isolates was determined by multilocus sequence typing (MLST) according to the Pasteur scheme, dual-sequence typing of blaOXA−51-like and ampC genes, and RAPD-PCR method.ResultsAll isolates were carbapenem-resistant while susceptible to colistin, minocycline, doxycycline, and ampicillin-sulbactam. The intrinsic blaOXA−51-like was detected in all isolates, and blaOXA−23-like was identified in 92.5% of isolates. However, blaOXA−143-like and blaOXA−58-like genes were not detected among isolates. Four distinct blaOXA−51-like alleles were determined as follows: blaOXA−317 (67.0%), blaOXA−90 (9.4%), blaOXA−69 (17.0%), and blaOXA−64 (6.6%) and four ampC (blaADC) allele types including ampC-25 (6.6%), ampC-39 (9.4%), ampC-1 (17.0%), and blaADC−88 (67.0%) were identified. MLST (Pasteur scheme) analysis revealed four ST types including ST136 (singleton), ST1 (CC1), ST25 (CC25), and ST78 (singleton) in 71, 18, 7, and 10 of A. baumannii strains, respectively. Five RAPD clusters including A (1.9%), B (26.4%), C (57.5%), D (7.5%), and E (1.9%) were characterized and 5 (4.7%) strains were found to be singletons.ConclusionThe present study demonstrated that there was a high prevalence of blaOXA−23-like producing CRAB in the clinical setting. The majority of isolates belonged to ST136 (singleton). However, blaOXA−23-like producing multi-drug resistant international clones including ST1, and emerging lineages (e.g. ST25 and ST78) were also identified. Interestingly, in this study ST2 was not detected.

【 授权许可】

CC BY   
© The Author(s) 2023

【 图 表 】

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