Bacteriological Profile of Pus Samples and their Antibiotics Susceptibility Pattern in Tertiary Care Hospital

Abstract

Background: Pyogenic infections continue to be a major clinical concern and may be caused by a wide array of microorganisms, frequently involving mixed flora that necessitates the use of antimicrobial agents. The widespread misuse and overuse of antibiotics have accelerated the emergence of drug-resistant strains, posing challenges to effective treatment. Although the predominant bacterial species isolated from pus specimens often remain relatively consistent, their patterns of antimicrobial susceptibility are subject to variation across time and settings. In this context, the present study was designed to determine the bacteriological profile of pus isolates and to evaluate their antibiotic susceptibility trends.

Material and methods: A retrospective study was carried out from September 2024 to September 2025. 170 pus samples were collected during study period were included. The samples were cultured on BHIA and MacConkey agar. After aerobic incubation at 37^o C for 18-24 hours, organisms were identified by standard methods and antibiotic susceptibility was tested by Kirby Bauer disc diffusion method. and Methicillin resistant Staphylococcus aureus (MRSA) by Cefoxitin 30 µg disc

Results: Of 170 pus samples collected, 100 (58.82 %) pus samples were positive cultures and no growth was in 58 pus samples (34.11%) , in 12 sample (7.05%) mixed growth seen. S. aureus 33(33%) was most common Gram positive isolate and E.coli 32 (32%), was most common gram negative isolate. MDR seen in 10 (10%)  and MRSA in 13(13%) S. aureus isolates. Most of gram negative isolates were susceptible to Amikacin (87.1% ), Chloramphenicol (88.9%) and Netilin (83.3%)  and gram positive isolates to doxycycline (96.7%), Chloramphenicol (96.2%) and linezolid (93.9%).

Conclusion: In our observations, resistance against beta-lactam group antibiotics was found to be significantly higher, posing a major clinical concern. Addressing this issue requires strict avoidance of indiscriminate antibiotic use. In addition, continuous monitoring of resistance patterns is essential for formulating effective treatment guidelines that can help lower both morbidity and mortality rates.