PHENOTYPIC AND GENOTYPIC CHARACTERIZATION OF MULTIDRUG-RESISTANT ACINETOBACTER BAUMANNII ISOLATES IN A TERTIARY CARE HOSPITAL IN GUNTUR: A POST-PANDEMIC ANALYSIS
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Keywords
Acinetobacter baumannii, Multidrug Resistance, Carbapenemase, blaOXA-23, Post-Pandemic, Guntur, PCR.
Abstract
Background: The COVID-19 pandemic significantly altered antimicrobial consumption patterns, leading to an accelerated rise in multidrug-resistant (MDR) organisms. Acinetobacter baumannii has emerged as a formidable "ESKAPE" pathogen, particularly in critical care settings, due to its ability to survive on abiotic surfaces and acquire diverse resistance mechanisms. This study aims to evaluate the current phenotypic and genotypic landscape of A. baumannii in the post-pandemic context at a tertiary care hospital in Guntur.
Methods: A cross-sectional study will be conducted at the Department of Microbiology, Katuri Medical College and Hospital. Various clinical specimens (sputum, pus, blood, and endotracheal aspirates) will be processed for the isolation of A. baumannii. Phenotypic antimicrobial susceptibility testing (AST) will be performed using the Kirby-Bauer disc diffusion method and Minimum Inhibitory Concentration (MIC) determination for Carbapenems and Colistin, following CLSI guidelines. Carbapenemase production will be screened using the Modified Carbapenem Inactivation Method (mCIM). Subsequently, Multiplex PCR will be employed to detect key resistance genotypes, specifically the blaOXA-23-like, blaOXA-51-like, and blaNDM-1 genes.
Results (Projected): It is anticipated that the study will reveal a high prevalence of Carbapenem-Resistant Acinetobacter baumannii (CRAB). Based on current regional trends, a significant correlation is expected between phenotypic carbapenem resistance and the presence of blaOXA-23 and blaNDM-1 genes. The "post-pandemic" analysis is expected to show an upward shift in MIC values compared to historical pre-2020 data, highlighting the impact of increased biocidal and antibiotic pressure during the pandemic years.
Conclusion: The findings will underscore the critical need for molecular surveillance in identifying the reservoirs of resistance. The high genetic diversity and resistance levels of A. baumannii in the Guntur region necessitate a stringent reinforcement of Antimicrobial Stewardship (AMS) programs and enhanced infection control protocols to mitigate the spread of these "superbugs" in the clinical environment.
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Dr. Raj Omprakash Angnani
Assistant Professor, Department Of Microbiology, Katuri Medical College, Hospital, Guntur
