Bacteriological Profile And Antibiogram Analysis: A Retrospective Study From A Tertiary Care Hospital In North India

Abstract

Background: Healthcare-associated infections (HAIs) contribute significantly to morbidity,
mortality, and healthcare costs, particularly in developing countries. The rising prevalence of multidrug
resistant organisms necessitates continuous surveillance of local bacteriological profiles and antimicrobial
susceptibility patterns. Objectives: To determine the bacteriological spectrum and analyze antimicrobial
susceptibility patterns of clinical isolates from bloodstream, urinary tract, respiratory tract, and surgical site
infections in a tertiary care hospital. Materials and Methods: This retrospective observational study was
conducted in the Department of Microbiology at a tertiary care center in North India from July 2024 to June
2025. All culture-positive clinical samples were included. Bacterial identification was performed using
standard microbiological methods, and antimicrobial susceptibility testing was done using the Kirby–Bauer
disk diffusion method. Results were interpreted as per Clinical and Laboratory Standards Institute (CLSI)
guidelines. Results: A total of 916 isolates were analyzed. Gram-negative organisms predominated across all
infection types. Escherichia coli and Klebsiella pneumoniae were the most common pathogens. Colistin
showed 100% sensitivity among Gram-negative isolates. Carbapenems demonstrated moderate sensitivity,
whereas high resistance was observed to cephalosporins and fluoroquinolones. Gram-positive organisms,
including Staphylococcus aureus and Enterococcus species, showed 100% sensitivity to vancomycin, linezolid,
and daptomycin. In urinary tract infections, E. coli showed high sensitivity to nitrofurantoin and fosfomycin.
Conclusion: Gram-negative bacteria predominate in HAIs with increasing antimicrobial resistance. Regular
surveillance and institution-specific antibiograms are essential for guiding empirical therapy and
strengthening antibiotic stewardship. [Tiwari U Natl J Integr Res Med, 2026; 17(1): 39-44, Published on Dated:
07/07/2026]