Different pattern of viral infections and clinical outcomes in patient with acute exacerbation of chronic obstructive pulmonary disease and chronic obstructive pulmonary disease with pneumonia.

Respiratory viruses are well-known causes of acute exacerbation of chronic obstructive pulmonary disease (AE-COPD) and also important pathogens for concomitant pneumonia in COPD (CP-COPD). However, the differences in a viral infection pattern and clinical impacts of respiratory viruses between the two groups have not been well investigated. The clinical and microbiological data from COPD patients admitted with AE-COPD (n = 281) or CP-COPD (n = 284) between January 2010 and December 2012 were reviewed. After excluding 88 patients (40 with AE-COPD and 48 with CP-COPD) who did not undergo a multiplex RT-PCR test for respiratory viruses, the demographic characteristics, identified viruses, and clinical outcomes of the AE-COPD and CP-COPD groups were compared. Respiratory viruses were identified in 41.9% of AE-COPD group and 33.5% of the CP-COPD groups. The most common virus was influenza virus in the AE-COPD group (33.7%) versus human coronavirus (24.1%) in the CP-COPD group. Influenza virus was significantly more common in the AE-ACOPD group than in the CP-COPD group (P < 0.01). In-hospital mortality of AE-COPD and CP-COPD were 1.2% and 12.3%, respectively (P < 0.01). Among CP-COPD patients, in-hospital mortality of patients with only viral infection group, only bacterial infection group, and viral-bacterial co-infection were 2.6%, 25.8%, and 17.5%, respectively (P = 0.01). Respiratory viruses were commonly identified in both AE-COPD and CP-COPD, influenza virus and human coronavirus were the most common viruses identified in AE-COPD and CP-COPD patients, respectively. The mortality rates of only viral infection group was significantly lower than only bacterial infection or viral-bacterial co-infection group in CP-COPD patients. J. Med. Virol. 88:2092-2099, 2016. © 2016 Wiley Periodicals, Inc.