Prevalence and Antimicrobial Susceptibility Patterns of Multidrug-resistant Organisms: A Retrospective Observational Study from a Tertiary Care Hospital
Year: 2026
Type: article
Abstract: Introduction: Antimicrobial Resistance (AMR) has emerged as a major threat to effective clinical care, significantly limiting therapeutic options and worsening patient outcomes. Tertiary care hospitals represent high-risk environments for the emergence and dissemination of Multidrug-Resistant Organisms (MDROs), particularly among critically-ill patients exposed to broadspectrum antimicrobial therapy. The increasing prevalence of multidrug resistance across key hospital pathogens highlights a concerning shift toward difficult-to-treat infections, underscoring the need for institution-specific surveillance data. Aim: To evaluate the prevalence and antimicrobial susceptibility patterns of MDROs in a tertiary care hospital. Materials and Methods: This retrospective observational study was conducted from January to June 2025 at the Department of Microbiology, Dr. M.K. Shah Medical College and Research Centre, Ahmedabad, Gujarat, India. A total of 530 non-duplicate bacterial isolates from clinical specimens were included. Isolates were identified using colony morphology, Gram staining, standard biochemical tests, and/or the VITEK 2 Compact system. Antimicrobial Susceptibility Testing (AST) was performed by the Kirby–Bauer disk diffusion technique and/or the VITEK 2 Compact system, with interpretation in accordance with Clinical and Laboratory Standards Institute (CLSI) M100 Ed35 2025 guidelines. Data were analysed using WHONET 2024. Statistical analysis was performed using appropriate statistical methods. Categorical variables were summarised as frequencies and percentages. Associations between categorical variables were assessed using the Chi-square test. A p-value of <0.05 was considered statistically significant. Results: Of 530 bacterial isolates, 320 (60.4%) were identified as MDROs. The MDRO distribution was dominated by carbapenem-resistant Enterobacterales (CRE) 108 (33.75%), followed by ESBL producers 77 (24.06%) and CarbapenemResistant Acinetobacter Baumannii (CRAB) 70 (21.88%), with lower proportions of Methicillin-Resistant Staphylococcus aureus (MRSA) 40 (12.5%), carbapenem-resistant Pseudomonas aeruginosa 24 (7.5%), and VRE 1 (0.31%). MDROs were more frequent among inpatients, 291 (90.94%), particularly in intensive care units 127 (39.7%), and showed higher prevalence in older age groups ≥60 years (53.13%). Wound 101 (31.56%) and respiratory 99 (30.94%) specimens constituted the major sources of isolation. Conclusion: The present study demonstrates a concerning institutional multidrug resistance landscape that compromises the effectiveness of commonly used antimicrobials. The institution-specific resistance patterns generated in this study support a data-driven recalibration of empirical antimicrobial therapy, while reinforcing the need for sustained antimicrobial stewardship and strengthened infection prevention measures.
Language: English
Subfield: Molecular Medicine
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $275
OpenAlex ID: W7223349423