Year: 2026 | Month: June | Volume: 16 | Issue: 6 | Pages: 152-157
DOI: https://doi.org/10.52403/ijhsr.20260617
Antibiotic Sensitivity Pattern of Escherichia coli Isolated from Various Clinical Samples in a Tertiary Care Hospital in Maharashtra: A Retrospective Observational Study
Nilu Shahi1, Vishakha V. Shikhare2, Pankaj Joshi3
1Assistant Professor, Department of Microbiology, R.C.S.M. Government Medical College, Kolhapur, Maharashtra, India
2Associate Professor, Department of Microbiology, R.C.S.M. Government Medical College, Kolhapur, Maharashtra, India
3Associate Professor, Department of Microbiology, Government Medical College, Miraj, Maharashtra, India
Corresponding Author: Dr. Nilu Shahi
ABSTRACT
Background: Escherichia coli remains a leading bacterial pathogen in routine diagnostic microbiology and is frequently implicated in urinary tract infection, wound infection and bloodstream infection. Rising antimicrobial resistance has reduced the reliability of many empirical regimens; therefore, institution-specific susceptibility data are required for rational antibiotic selection and stewardship.
Methods: This retrospective observational study was conducted in a tertiary care hospital in Maharashtra, India. Clinical specimens received from January 2023 to June 2023 were processed by standard bacteriological methods. E. coli isolates were identified using colony morphology, Gram staining and conventional biochemical reactions. Antimicrobial susceptibility testing was performed by the Kirby-Bauer disc diffusion method on Mueller-Hinton agar, and results were interpreted according to CLSI recommendations.
Results: Of 2,559 clinical samples processed, 579 (22.62%) yielded E. coli. Urine was the commonest source of isolation (363; 62.69%), followed by wound swab or pus (150; 25.90%), blood (36; 6.21%) and sputum (30; 5.18%). Very high resistance was observed to ampicillin (95.85%), cefazolin (94.82%), cefuroxime (92.23%), ceftriaxone (83.94%), cefepime (80.83%) and ciprofloxacin (79.79%). Imipenem showed the highest susceptibility (93.26%), followed by piperacillin-tazobactam (77.73%) and amikacin (72.02%). Among urinary isolates, nitrofurantoin retained good activity (85.12% susceptible), whereas norfloxacin susceptibility was low (20.67%).
Conclusion: The isolates demonstrated extensive resistance to commonly used beta-lactams and fluoroquinolones. Imipenem, piperacillin-tazobactam and amikacin showed comparatively better in vitro activity, and nitrofurantoin remained a useful oral option for uncomplicated lower urinary tract infection. Periodic local antibiogram review and judicious antimicrobial use are essential to preserve treatment options.
Key words: Escherichia coli; antimicrobial resistance; antibiogram; urinary tract infection; beta-lactam resistance.