Detection of rhinovirus in induced sputum at exacerbation of chronic obstructive pulmonary disease

Common colds are associated with exacerbations of chronic obstructive pulmo nary disease (COPD), However, the role of the common cold virus (human rhin ovirus) in the production of symptoms and lower airway inflammation at COPD exacerbation is unknown, Thirty three patients with moderate-to-severe COPD were seen at baseline, w hen the number of chest infections in the previous year was noted, and acut ely at COPD exacerbation. Within 48 h after the onset of the exacerbation a nd at baseline, nasal aspirates and induced sputum were taken for rhinoviru s reverse transcriptase polymerase chain reaction (RT-PCR) analysis and det ermination of cytokine levels. Symptoms, recorded on diary cards, were note d and forced expiratory volume in one second (FEV1) and forced vital capaci ty (FVC) measured. At exacerbation, mean FEV1 and FVC fell significantly from baseline (p<0.00 1). Ten of 43 exacerbations were associated with rhinovirus infection, dete cted in induced sputum, In four of these, nasophageal samples contained no detectable rhinovirus, All baseline samples were negative for rhinovirus, T he simultaneous presence of increased nasal discharge/nasal congestion (in 26 of the 43 exacerbations) and increased sputum (29 exacerbations) was str ongly associated with the presence of rhinovirus (odds ratio 6.15; p=0.036) . Total symptom scores were greater for rhinovirus as compared to nonrhinov irus exacerbations (p=0.039). Median baseline sputum interleukin-6 levels r ose from 90.2 to 140.3 pg.mL(-1) at exacerbation (p=0.005); the change was greater in the presence of rhinovirus infection (p=0.008), Rhinovirus infection can be detected at chronic obstructive pulmonary disea se exacerbation. This is associated with elevation of lower airway interleu kin-6 levels, which may mediate lower airway symptom expression during chro nic obstructive pulmonary disease exacerbations.