Pathogens Isolated and Their Association With the Long-Term Outcome in Patients With Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Background: Most of the acute exacerbations of chronic obstructive pulmonary disease (COPD) are due to infections, mostly due to bacteria and viruses. There is a need to study the outcome of microbe-induced airway inflammation. Materials and methods: It is an observational follow-up study from the pulmonary medicine department of Kalinga Institute of Medical Sciences with the participation of the Regional Medical Research( )Center, Bhubaneswar, from October 2018 to February 2022. Patients who were admitted with acute exacerbation of COPD and treated as per GOLD (Global Initiative for Chronic Obstructive Lung Disease) 2021 guidelines were included in the study. Those patients in the severe category, who had clinically recovered, had undergone pulmonary physiotherapy, were on prescribed medications and home oxygen therapy after discharge, were followed up every three months by telephone calls. Any exacerbation, clinical stability, or mortality information was recorded. Results: Out of 197 cases, the majority were elderly, males, smokers, and belonged to urban areas; in total, 102 (51.8%) microbes were isolated as etiological agents of infective exacerbation in which 19.79% were viruses and 23.35% were bacteria, while coinfection was found in 8.62% cases. Among the viruses, rhinovirus, influenza virus, and respiratory syncytial virus were the major isolates. Among the bacteria, mostly gram-negative organisms such as Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa were isolated. Readmission was more among patients with coinfection. Conclusion: Acute exacerbation of COPD was mostly seen in males in the age group of 61-80 years. Rhinovirus and influenza A virus were the two most common viral isolates, and among the bacterial isolates, Acinetobacter baumannii and Klebsiella pneumoniae were predominantly detected. Poor clinical outcomes were noticed more among the coinfection group.