Bacterial Etiology and Antibiotic Susceptibility Patterns in Acute Exacerbations of Chronic Obstructive Pulmonary Disease: Implications for Targeted Antimicrobial Therapy

Abstract

Background: Hospitalization is frequently required for acute exacerbations of chronic obstructive pulmonary disease (AECOPD), which have a substantial impact on patient morbidity and mortality. These exacerbations are mostly caused by bacterial infections and managing them effectively is made more difficult by the growing trend of antibiotic resistance. Objective: To identify the bacterial infections that cause AECOPD and ascertain their patterns of antibiotic susceptibility to inform the development of suitable treatment plans. Methodology: A prospective, cross-sectional observational study was carried out over a period of six months. A total of 110 participants with clinically confirmed AECOPD who were at least 40 years old and had not taken antibiotics during the previous 48 hours were included in the study. Following the recommendations set forth by the Clinical and Laboratory Standards Institute (CLSI), sputum samples were obtained and submitted to Gramme staining, culture, and antibiotic susceptibility testing utilizing the Kirby-Bauer disc diffusion method. Results: Among study cases, sputum samples of 82 (74.5%) had notable bacterial growth. Gram-negative bacteria accounted for 82.9% of the total, with the most frequent isolates being Klebsiella pneumoniae (34.1%) and Pseudomonas aeruginosa (24.4%). Haemophilus influenzae (9.8%) and Streptococcus pneumoniae (12.2%) were commonly found among Gram-positive organisms. It is noteworthy that 43.9% of isolates were multidrug-resistant (MDR), with Pseudomonas aeruginosa (60%) and Acinetobacter baumannii (75%) having the highest MDR frequencies. Conclusion: The study concludes that Gram-negative bacilli with high rates of multidrug resistance are the primary cause of the notable incidence of bacterial infections in AECOPD. These results highlight the need for regular sensitivity testing and sputum culture to direct targeted antibiotic treatment, enhancing patient outcomes and halting the spread of antibiotic resistance.