TITLE:
Molecular Detection of Carbapenemase Genes in Extensive Drug Resistant Acinetobacter baumannii Clinical Isolates from ICU Patients, Khartoum
AUTHORS:
Shirehan M. Ibrahim, Elamin M. Ibrahim, Omer A. Ibrahim, Omnia M. Hamid, Hassan A. Alaziz
KEYWORDS:
Carbapenem Producing Acinetobacter baumannii (CPAB), Intensive Care Unit (ICU) Patients, Extensive Drug-Resistant (XDR), Colistin
JOURNAL NAME:
Open Journal of Medical Microbiology,
Vol.12 No.1,
March
24,
2022
ABSTRACT: Background: The emergence of carbapenemase producing Acinetobacter baumannii is increasingly reported nowadays and constitutes a
major problem to the intensive care unit (ICU) patients with notable
extensive-drug resistance ability. The study investigates carbapenemase
producing A. baumannii strains exhibiting an extensively drug-resistant
(XDR) phenotype, isolated from ICU patients in Khartoum. Methods: A
total of 100 nonduplicate Gram-negative coccobacilli strains were obtained from
microbiology laboratory of ICU patients’ clinical isolates. Molecular identification of A. baumannii was performed by targeting 16S rRNA gene using specifically designed
primers. Then, XDR strains were determined by susceptibility testing (disc
diffusion). For detection of carbapenemase genes Polymerase chain reaction
(PCR) was carried out. Result: Of 100 ICU clinical isolates, 38 (38.0%) was confirmed A. baumannii strains, those strains showed 100% carbapenem resistance and 60.5% extensive
drug resistance to the antibiotics tested. The frequency of carbapenemase
producer was 57.9% (22/38) of carbapenem resistance A. baumannii (CRAB). The most common carbapenemase associated with
resistance was blaOXA gene followed by blaNDM and blaGES A. baumannii isolates. The co-occurrence of blaOXA-48-like and
blaNDM, blaOXA-23-like and blaOXA-51, and blaNDM-1 and blaOXA-51 was detected
in 22.7%, 18.2% strains and 4.5% respectively. A unique characteristic of our
findings was the coharbouring of the genes blaNDM-1, blaOXA-23-like, blaOXA-51
and blaOXA-143 in 9.1% strains (2/22), and this was the
first report in the Khartoum city, Sudan. Conclusion: We have
demonstrated for the first time a high prevalence of XDR-carbapenemase
producing A. baumannii clinical
isolates from ICU patients in Khartoum. Also an emergent blaOXA-143 was
reported as High-Risk Clones. This highlights the routine mentoring of XDR-carbapenemase
producing A. baumannii to avoid clone
dissemination in our region hospitals.