BACTERIOLOGICAL SPECTRUM AND ANTIBIOTIC SUSCEPTIBILITY PATTERNS IN PATIENTS WITH ACUTE EXACERBATION OF COPD ADMITTED TO A TERTIARY CARE CENTRE IN RAJASTHAN

Abstract

Acute exacerbations of Chronic Obstructive Pulmonary Disease (AECOPD) significantly contribute to morbidity, mortality, and healthcare burden, particularly in low- and middle-income countries. Bacterial infections are among the most common triggers, and increasing antimicrobial resistance complicates management. Regional bacteriological surveillance is essential for optimizing empirical antibiotic therapy.

Objective: To determine the bacteriological profile and antibiotic susceptibility patterns among patients hospitalized with AECOPD at a tertiary care center in Southern Rajasthan.

Methods: This hospital-based cross-sectional study included 83 clinically diagnosed AECOPD patients aged ≥45 years. Sputum samples fulfilling adequacy criteria (<10 squamous epithelial cells and >25 pus cells/LPF) were processed for Gram stain, aerobic culture, and antibiotic susceptibility testing using the Kirby–Bauer disc diffusion method as per CLSI guidelines. Demographic, clinical, and microbiological data were analyzed using SPSS v21. Categorical variables were compared using Chi-square test and continuous variables using Student’s t-test, with p<0.05 considered statistically significant.

Results: Most patients were males (85.54%), within 61–65 years age group, and resided in rural areas (77.10%). Underweight BMI was observed in 44.58% of participants. Purulent or mucopurulent sputum predominated (75.90%). Pathogenic bacterial growth was detected in 43 (51.80%) samples, with Gram-negative bacilli accounting for 81.39% of isolates. The most commonly isolated pathogens were Pseudomonas aeruginosa (32.55%) and Klebsiella pneumoniae (23.25%), followed by Staphylococcus aureus (13.95%) and Haemophilus influenzae (11.62%). Antibiotic susceptibility testing revealed highest sensitivity to Amikacin, Gentamicin, Piperacillin–Tazobactam, and Ciprofloxacin, while macrolides demonstrated high resistance.

Conclusion: Bacterial infection plays a major role in AECOPD, with Gram-negative organisms predominating. Emerging resistance to commonly prescribed antibiotics—especially macrolides—necessitates evidence-based empirical antibiotic selection. Local antibiograms, rational antimicrobial use, and preventive strategies including smoking cessation, vaccination, and nutritional support are vital to improving clinical outcomes and reducing resistance trends.