TY - JOUR T1 - Our experience of procalcitonin assay in identifying bacterial COPD exacerbations JF - European Respiratory Journal JO - Eur Respir J VL - 38 IS - Suppl 55 SP - p571 AU - Christopher Gough AU - Parthipan Pillai AU - Rohinton Mulla Y1 - 2011/09/01 UR - http://erj.ersjournals.com/content/38/Suppl_55/p571.abstract N2 - Background: Procalcitonin (PCT) is a pre-hormone which is raised in bacterial infection.Aim of study: To evaluate the benefit of measuring PCT level in recognising bacterial from non bacterial COPD exacerbations.Method: We prospectively evaluated 24 COPD patients who were admitted with an exacerbation. They had PCT, C-reactive protein (CRP), white blood cell (WBC) measurements and a chest radiograph (CXR). Use of antibiotics were recorded.Results: 6 patients had CXR findings of consolidation and 5 of them had high PCT indicating bacterial infection. 1 patient had a moderately elevated PCT which could be due to early sampling.In 18 patients who had normal CXR findings, 3 had positive PCT and of these, 1 had high CRP and WBC indicating true bacterial infection. 1 had high CRP with normal WBC which could be due to atypical bacterial infection. 1 had normal CRP with high WBC which could be due to spuriously low CRP result.In 15 patients who had negative PCT, 7 had normal CRP and WBC indicating no bacterial infection. 2 of them had normal CRP but slightly raised WBC and we feel the raised WBC were due to preceding steroid treatment. 3 of them had raised CRP and normal WBC and 3 had both raised CRP and WBC. These may be due to bacterial infection, and the negative PCT represented early sampling. All patients had antibiotics on admission.Conclusion: Many patients with COPD exacerbation are treated with antibiotics without bacterial infection. High PCT level indicates bacterial infection in these patients. The converse is also true but this should be used in conjunction with CRP and WBC levels. When normal PCT level is associated with either raised CRP or WBC, a second late PCT level should be measured. ER -