Phenotypic Detection of Metallo-Beta Lactamases in Acinetobacter baumanni in a Tertiary Care Hospital of Western Rajasthan, India
Department of Microbiology, Dr. S. N Medical College, Jodhpur, India
*Corresponding author
Abstract:
Acinetobacter spp. is a gram negative cocco-bacilli bacteria, correlated with an important opportunist pathogen in a health care institutions worldwide. Its multiple drug resistance (MDR) is of great concern because of its intrinsic and acquired resistance mechanisms, limiting the treatment options. Acinetobacter spp. produces carbapenamases like metallo-β-lactamases (MBLs), which hydrolyze a varieties of β-lactams antibiotics including penicillin, cephalosporins and carbapenems. Present study was designed to determine the MBL production in Acinetobacter baumanni and to evaluate the phenotypic test methods for thedetection of MBL production in imipenem-resistant clinical isolates of Acinetobacter baumanni. Present study was conducted from September 2022 to December 2024 at the department of Microbiology, Dr. S. N Medical College and attached hospitals, Jodhpur, Rajasthan. Present study was a hospital based prospective study. Totally 178Acinetobacter baumanni i isolates were collected from different clinical specimens. Imipenem resistant isolates were subjected to 4 different phenotypic test methods for the detection of Metallo-beta –lactamases (MBL), Imipenem + EDTA combined disc test, double disc synergy test, Modified Hodge test and MBL E-test. Totally 178 Acinetobacter baumanni i isolates were collected out of which Imipenem resistant were 104 (58. 42%). Amongst these 104 (58. 42%) isolates, 57 (67. 05%) were MBL positive by CDT, 100 (96. 15%) DDST 26 (25%) MHT56 (53. 84%) and MBL E-test method 104 (100%). The present study showed that E-test was the most sensitive and specific phenotypic method followed by the combined disc test. Strict antibiotic stewardship programe and infection control measures can decreases the positivity rate of the superbugs in the hospital settings.
Keywords:
Metallo-beta-lactamases (MBL), Combined disc test (CDT), Double disc synergy test (DDST), E strip test and Muller Hinton Agar (MHA).
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How to cite this article:
Vishakha Ashopa and Prabhu Prakash. 2026. Phenotypic Detection of Metallo-Beta Lactamases in
Acinetobacter baumanni In a Tertiary Care Hospital of Western Rajasthan, India.
Int.J.Curr.Microbiol.App.Sci.
15(7): 243-249
doi:
https://doi.org/10.20546/ijcmas.2026.1507.024
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