Bacteriological Profile and Antibiotic Susceptibility Pattern of Isolates from Wound Infections in a Tertiary Care Hospital

Abstract

Background: Wound infections, both surgical and traumatic, are among the most commonly encountered healthcare-associated infections, often leading to delayed healing, prolonged hospitalization, and increased antibiotic resistance. Periodic surveillance of microbial patterns and resistance profiles is critical to guide effective treatment.

Objective: To isolate and identify bacteria from wound infections and determine their antimicrobial susceptibility patterns.

Methods: This cross-sectional study included 220 wound swab or aspirate samples collected from patients with clinically evident wound infections over six months. All samples were cultured, and isolates were identified by standard biochemical methods. Antibiotic susceptibility testing was performed using the Kirby-Bauer disc diffusion method. Data were analyzed using descriptive statistics and chi-square test.

Results: Out of 220 samples, 178 (80.9%) showed significant growth. Staphylococcus aureus was the most common isolate (38.2%), followed by Escherichia coli (21.9%) and Pseudomonas aeruginosa (16.3%). Among S. aureus, 35.3% were methicillin-resistant (MRSA). Gram-negative isolates showed high resistance to cephalosporins and fluoroquinolones but were largely sensitive to amikacin and imipenem. Prior antibiotic use was significantly associated with multidrug-resistant (MDR) strains (p = 0.02).

Conclusion:S. aureus, including MRSA, remains the predominant pathogen in wound infections, while rising resistance among gram-negative bacilli underscores the need for prudent antibiotic use. Periodic antibiogram-based policy implementation is crucial for effective infection control.

Keywords: Wound infection, antibiotic resistance, MRSA, Staphylococcus aureus, microbiological surveillance