PT - JOURNAL ARTICLE AU - Nisha Rana AU - Bethan Barker AU - Koirobi Haldar AU - Hemu Patel AU - Vijay Mistry AU - Mitesh Pancholi AU - Michael Barer AU - Christopher Brightling AU - Mona Bafadhel TI - Association between qPCR bacterial load and airway inflammation in COPD DP - 2013 Sep 01 TA - European Respiratory Journal PG - P598 VI - 42 IP - Suppl 57 4099 - http://erj.ersjournals.com/content/42/Suppl_57/P598.short 4100 - http://erj.ersjournals.com/content/42/Suppl_57/P598.full SO - Eur Respir J2013 Sep 01; 42 AB - Background: In COPD bacterial colonisation is associated with a sputum neutrophilia and increased airway inflammation. Quantitative PCR (qPCR) is more sensitive than culture for bacterial detection. Relationships between sputum inflammatory mediators and pathogens quantified by qPCR in stable state are unclear.Methods: Sputum from 66 stable COPD patients was analysed for bacterial load (semi-quantitative culture [colony forming units/ml, CFU], qPCR for Haemophilus influenzae [HI], Streptococcus pneumoniae [SP] and Moraxella catarrhalis [MC]), differential cell counts (total cell count [TCC], neutrophil %, eosinophil %) and a panel of inflammatory mediators. Associations between bacterial load and both inflammatory mediators and differential cell counts were explored. Correlations were considered significant if p<0.01.Results: Positive correlations were found between CFU and TNFα (rs=0.42,p=0.001), IL1β (rs=0.39,p=0.001) and IL10 (rs=0.57,p<0.001). Several positive correlations were found between qPCR HI and inflammatory mediators (table 1). qPCR MC and qPCR SP did not positively correlate with CFU, sputum cell counts or any sputum inflammatory mediator.View this table:Table 1: Correlations between H. influenzae qPCR load and inflammatory mediatorsConclusions: Stable state H. influenzae qPCR load is associated with an increased sputum total cell count, neutrophil percent and inflammatory mediators in COPD. The same associations were not seen with qPCR S. pneumoniae and M. catarrhalis.