The Phenotypic profiling and blaTEM gene detection in multidrug resistant gram-negative bacteria isolated from hostel sanitary area
Antimicrobial resistance
Keywords:
antimicrobial resistance, sink drains, biofilm, lactamase, blaTEM gene, disk diffusionAbstract
Background: Antimicrobial resistance (AMR) is a major health concern across the world, with Gram-negative bacteria account for failing the therapeutic options available. Environmental reservoirs, such as sink drains in high-occupancy hostels have been recognized as the neglected hotspots for multidrug-resistant bacteria, has become an imminent health peril because it is associated with biofilm-mediated persistence and transmission of antimicrobial resistance.
Objective: This study aimed to investigate the phenotypic resistance patterns and detect blaTEM gene among the Gram-negative strains from the drainage system of hostel sanitary areas.
Methodology: The 80 swab samples were collected and cultured on a selective media to specifically isolate 50 resistant strains followed by performing antibiotic susceptibility testing using Kirby-Bauer disk diffusion method. PCR was conducted to confirm the presence of the blaTEM gene.
Results: Biochemical profiling identified various species with Escherichia coli and Acinetobacter spp. (18% each) were the most common, followed by Pseudomonas spp. and Salmonella spp. (12% each). While Enterobacter spp. and Stenotrophomonas spp. constituted 10% of isolates. Proteus spp. and Shigella spp. were identified as 8% and 6% respectively. The less frequently found organisms were Serratia spp. and Aeromonas spp. Antibiotic susceptibility testing revealed all isolates were resistant to ampicillin, with varying levels of resistance against CZC (98%), CIP (94%), ZOX (88%), CTX (82%), MEM (72%), CN (72%) and TBZ (68%), PCR analysis confirmed the presence of the blaTEM gene in 54% (95% CI: 40.4%–67.0%) of the resistant isolates.
Conclusion: In conclusion, the findings indicate that the hostel sanitary drainage system serves as a potential reservoir for MDR Gram-negative bacteria, many of which harbor the blaTEM gene. This underscores the urgent need for improved sanitation practices, regular microbial surveillance, strict infection control measures, and rational antibiotic usage to reduce the risk of resistant pathogen transmission in communal living environments.
Key words: Antimicrobial resistance, sink drains, biofilm, lactamase, Kirby-Bauer disk diffusion, and blaTEM gene
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