TO STUDY THE IN VITRO EVALUATION OF MINOCYCLINE EFFECTIVENESS AGAINST MULTIDRUG-RESISTANT GRAM-NEGATIVE BACILLI ISOLATES IN TERTIARY CARE CENTER OF LUCKNOW, INDIA
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Keywords
Minocycline, multidrug-resistant, gram-negative bacilli, antimicrobial resistance, meropenem
Abstract
Background: Multidrug-resistant gram-negative bacilli (MDR-GNB) represent a critical global health challenge due to their association with hospital-acquired infections and limited therapeutic options. Minocycline, a second-generation tetracycline, has re-emerged as a potential treatment option.
Aim: To evaluate the in vitro effectiveness of minocycline against MDR-GNB isolates and compare its activity with meropenem.
Methods: A prospective observational study was conducted over six months in the Department of Microbiology, IIMSR, Lucknow. Sixty-six MDR-GNB isolates from various clinical samples were identified using standard microbiological methods. Antimicrobial susceptibility testing was performed by the Kirby-Bauer disc diffusion method following CLSI guidelines.
Results: Of the 66 isolates, the majority were obtained from urine (43.9%) and pus (27.3%). The predominant organisms included Escherichia coli (30.3%), Acinetobacter spp. (22.7%), and Citrobacter spp. (19.7%). Minocycline demonstrated sensitivity in 34.8% of isolates, intermediate susceptibility in 10.6%, and resistance in 54.6%. Comparatively, meropenem showed 16.7% susceptibility and 83.3% resistance. Notably, 45.5% of isolates were susceptible to minocycline, including many strains resistant to meropenem.
Conclusion: Minocycline demonstrated promising in vitro activity against MDR-GNB, particularly against meropenem-resistant strains. Its role as a potential alternative therapeutic option warrants further clinical validation.
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Parinita Raj
Msc. Student, Department of Microbiology, Integral Institute of Medical Science and Research, Lucknow, Uttar Pradesh, India.
Dr. Shweta Kumari
Assistant professor, Department of Microbiology, Integral Institute of Medical Science and Research, Lucknow, Uttar Pradesh, India.
Sandeepika Dubey
Tutor, Department of Microbiology, Integral Institute of Medical Science and Research, Lucknow, Uttar Pradesh, India.