title: Association between respiratory viruses and exacerbation of COPD: a case-control study.
abstract: BACKGROUND
  Respiratory viral infection is the main cause of exacerbations of chronic obstructive pulmonary disease (COPD) in all age groups. The present study aimed to find out the association between viral infection in exacerbated and stable patients with COPD as well as evaluating the frequency of respiratory viruses in the Iranian exacerbated patients.
  
  
  METHODS
  The study included 170 patients as the sample group with acute exacerbations and a control group consisting of 96 stable patients over a period of 3 years. Reverse transcription- nested polymerase chain reaction (RT-nested PCR) and nested PCR methods were used to diagnose the presence of 16 respiratory viruses.
  
  
  RESULTS
  Viral infection was detected in 81 (47.6%) exacerbations and 24 (25%) stable patients (p < 0.05). Adenovirus was more frequent among the exacerbated patients than the stable patients (p < 0.05). Furthermore, influenza virus, respiratory syncytial virus, and enterovirus turned out to be the most common viruses in both groups. Moreover, respiratory viral co-infection has a possible role in exacerbation, severity, and longer hospitalization. Muscle pain and fever were found as significant symptoms in the infected patients with exacerbations.
  
  
  CONCLUSIONS
  The current study investigated the probable roles of the respiratory viruses, and dual infections during acute exacerbations of COPD. Since climate-dependent respiratory viral incidence patterns in Iran are often dissimilar, preparing a comprehensive global model of respiratory infections with seasonal details in different geographical zones might decrease the morbidity and mortality rate in exacerbations of COPD.
authors: From the Department of Microbiology, North Tehran Branch, Islamic Azad University , Tehran , Iran.
authors: Seyedeh Somayeh
authors: SS
authors: Hosseini
authors: Ehsan
authors: E
authors: Ghasemian
authors: Hamidreza
authors: H
authors: Jamaati
authors: Bahman
authors: B
authors: Tabaraie
authors: Zeynab
authors: Z
authors: Amini
authors: Kelsey
authors: K
authors: Cox
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D060085:Coinfection; D018450:Disease Progression; D004770:Enterovirus / Q000302:isolation & purification; D005260:Female; D006801:Humans; D007492:Iran / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D017817:Nasal Lavage Fluid / Q000821:virology; D010614:Pharynx / Q000821:virology; D016133:Polymerase Chain Reaction; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications* / Q000453:epidemiology / Q000503:physiopathology*; D012136:Respiratory Syncytial Viruses / Q000302:isolation & purification; D012141:Respiratory Tract Infections / Q000150:complications* / Q000453:epidemiology / Q000821:virology*; D012621:Seasons; D013183:Sputum / Q000821:virology; D013997:Time Factors; D014777:Virus Diseases / Q000150:complications* / Q000453:epidemiology
keywords: Iran; Viral infection; adenovirus; polymerase chain reaction