Biofilm formation and beta lactamase resistance of Acinetobacter isolates obtained from CCU patients

International Journal of Molecular and Clinical Microbiology

دوره 15، شماره 1، مهر 2025، صفحه 2190-2197   

نوع مقاله: Research Article

شناسه دیجیتال (DOI): 10.22034/ijmcm.2025.710274

نویسندگان

sanaz ziaaldini¹؛ nadia kazemipour^{* 2}

¹Department of Microbiology, Ke.C, Islamic Azad University, Kerman, Iran.

²Associate professor, Department of Microbiology, Ke.C, Islamic Azad University, Kerman, Iran.

چکیده

Acinetobacter is clinically important pathogen with extensive resistance to various antibiotics This study aimed to antimicrobial resistance pattern in Acinetobacter species isolated from venous catheters. Extended-spectrum beta-lactamases (ESBLs) isolates, Cell Surface Hydrophobicity (CSH) index and biofilm formation was assayed. Sampling was performed from intravenous catheters people hospitalized in Kerman hospitals. Antibiogram tests were performed by disks ciprofloxacin (5 µg), ceftazidime (30 µg), ceftriaxone (30 µg), cefotaxime (30 µg), gentamicin (10 µg), ampicillin (10 µg), colistin (10 µg) Imipenem (10 µg), oxacillin (1 µg). Disks of ceftazidime and cefotaxime, both alone and combined with clavulanic acid were used to identify beta lactamase producing isolates. CSH was determined by the affinity test to xylene. Biofilm formation was analyzed in glass and polypropylene under shaking and non-shaking conditions test tubes. Twenty isolates of Acinetobacter were identified, of which 75% to ciprofloxacin, 100% to ceftazidime, 100% to ceftriaxone, 85% to cefotaxime, 75% to gentamicin, 80% to amikacin, 100% to oxacillin, 95% to imipenem, 85% were resistant to colistin and cefixime. In phenotypic screening of ESBLs positive isolates, 4 (20%) of the isolates were beta-lactamase positive. Five isolate of Acinetobacter showed above 70 % hydrophobicity. All five isolates with CSH Index above 70 % formed moderate biofilm. Analysis of biofilms formed on glass and polypropylene surfaces showed shaking conditions were suitable for biofilm formation and all five isolates formed strong biofilm in shaking condition. Adhesion of Acinetobacter on polypropylene was higher than on glass surfaces.

کلیدواژه‌ها

Acinetobacter؛ Beta-lactamase؛ CSH Index؛ Biofilm؛ Antibiotic resistance؛ Molecular identification