Culture Sensitivity Patterns of Bacterial Isolates from Patients with Empyema: A Cross-Sectional Study

Abstract

Background: Empyema thoracis is a serious complication of pneumonia and other pleural infections, often requiring prompt antimicrobial therapy. Understanding the culture sensitivity patterns of bacterial isolates is crucial for guiding empirical treatment and improving patient outcomes. Objective: To determine the prevalence and antibiotic susceptibility profiles of bacterial pathogens isolated from pleural fluid samples of patients diagnosed with empyema. Methodology: A cross-sectional study was conducted over 12 months at a tertiary care hospital in Peshawar, Pakistan. Pleural fluid samples from 150 patients with clinically and radiologically confirmed empyema were collected and cultured. Isolates were identified using standard microbiological techniques, and antibiotic susceptibility testing was performed using the Kirby-Bauer disk diffusion method in accordance with CLSI guidelines. Results: Out of 150 samples, 112 (74.7%) yielded positive cultures. The most common isolates were Staphylococcus aureus (34.8%), Streptococcus pneumoniae (21.4%), Klebsiella pneumoniae (17.0%), and Pseudomonas aeruginosa (14.3%). S. aureus showed high sensitivity to vancomycin (96.8%) and linezolid (93.5%) but was resistant to penicillin (87.1%). Gram-negative isolates exhibited high resistance to third-generation cephalosporins but retained sensitivity to carbapenems and colistin. Conclusion: The study highlights the predominance of multidrug-resistant organisms in empyema cases, emphasizing the need for routine culture and sensitivity testing. Empirical therapy should be guided by local antibiograms to ensure optimal outcomes.