TY - JOUR T1 - Is CRP a reliable diagnostic tool for infective exacerbations of COPD? JF - European Respiratory Journal JO - Eur Respir J VL - 42 IS - Suppl 57 SP - P2070 AU - Numbere Numbere AU - Milan Bhattacharya AU - Ajikumar Kavidasan Y1 - 2013/09/01 UR - http://erj.ersjournals.com/content/42/Suppl_57/P2070.abstract N2 - CRP, a marker of infection and inflammation, is often used to help type COPD exacerbations as infective or non-infective and so decide need for sputum cultures and antibiotics. This is more so if other signs of infection e.g. fever, sputum purulence are absent.Bacterial growth from sputum reflects infection or colonisation and can greatly alter immediate and long-term management of COPD patients.We looked at how predictive CRP levels are of bacterial growth from sputum culture in patients admitted to a district hospital with COPD exacerbations. We posed 2 questions:1. Is there a difference in CRP between positive and negative sputum groups?2. Is a particular CRP level predictive of positive sputum culture?METHODWe cross-referenced positive sputum cultures from 2008 to 2010 with discharges from the same time coded with keywords “COPD”, “exacerbation”. Only patients with CRP levels and sputum sent within 24 hours of admission were included.RESULTSWe found 122 cases: 79 male, 43 female, mean age 70.8 years. 67 / 122 had positive sputum cultures. Though the sputum positive CRP mean was higher, we found no significant difference between the groups: mean CRP for sputum positives was 89.6 (CI 62.4 - 116.7) and for sputum negatives 70.6 (CI 49.1 - 92.1); P = 0.29.With CRP at 100 as a screen, sensitivity for positive sputum was 28.4%, specificity 72.7%, positive predictive value (PPV) 55.9% and negative predictive value (NPV) 45.5%. With a CRP of 50, sensitivity was 50%, specificity 58.2%, PPV 58.9% and NPV 49.2%.CONCLUSIONWe contend that CRP is not a reliable predictor of sputum positivity in COPD exacerbations and so there must be more reliance on clinical findings to decide need for sputum cultures and antibiotics. ER -