RT Journal Article SR Electronic T1 Rhinovirus infection induces secondary bacterial infection in COPD JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP 196 VO 38 IS Suppl 55 A1 Patrick Mallia A1 Joseph Footitt A1 Rosa Sotero A1 Annette Jepson A1 Gregory Oleszkiewicz A1 Julia Aniscenko A1 Onn Min Kon A1 Papi Alberto A1 Sebastian Johnston A1 Girolamo Pelaia YR 2011 UL http://erj.ersjournals.com/content/38/Suppl_55/196.abstract AB Aim: To investigate the relationship between rhinovirus infection and secondary bacterial infection.Methods: We performed experimental rhinovirus (RV) infection in COPD subjects (GOLD stage II, N=20), smokers with normal lung function (SMK, N=21) and non-smokers (NS, N=11). Sputum was collected at baseline and following inoculation. RV infection was confirmed with PCR and semi-quantitative bacterial culture performed. SLPI, elafin and neutrophil elastase (NE) were measured in sputum by ELISA.Results: 1 subject with bacteria in baseline sputum was excluded. Following RV infection bacteria were detected in 65% of COPD, 19% of SMK and 30% of NS (P=0.0086). 92% of bacteria in the COPD group were pathogenic bacteria, compared with 50% in SMK and 33% in NS (P=0.045). Peak sputum virus load was on day 5 and peak bacterial load on day 15. Following RV infection sputum SLPI and elafin fell from baseline in the bacteria+ve subjects and increased in the bacteria-ve subjects.Figure 1Peak virus load (8.4±0.72 vs 6.5±0.6 copies/mL,P=0.049) and sputum NE on day 9 (0.65±0.14 vs 0.31±0.07μg/mL, P=0.026) were higher in subjects with bacterial infection compared to those without.Conclusions: Secondary bacterial infection is common following rhinovirus infection in COPD and is associated with higher virus loads and NE, but lower levels of SLPI and elafin in sputum. Degradation of SLPI and elafin by NE may be a mechanism of increased susceptibility to bacterial infection.