RT Journal Article SR Electronic T1 Value of serum procalcitonin levels in the differential diagnosis of pneumonia and pulmonary embolism JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP p2489 VO 38 IS Suppl 55 A1 Ayse Yeter A1 Gungor Camsari A1 Gulcihan Ozkan A1 Aygun Gur A1 Nur Dilek Bakan A1 Mehmet Bayram YR 2011 UL http://erj.ersjournals.com/content/38/Suppl_55/p2489.abstract AB Objective: Procalcitonin (PCT), a precursor hormone of calcitonin is secreted from the thyroid. It was increased in blood in bacterial infections. The aim of the study was to determine the serum procalcitonin levels in differentiating community-acquired pneumonia (CAP) from pulmonary embolism (PE).Methods and patients: Fifty-eight patients with ≥1 of the following symptoms; fever, cough, dyspnoea, haemoptysis, sputum, chest pain and lesion on chest x ray were included to the study. Thirty patients were diagnosed as CAP and 27 patients as PE. One patient with suspected PE was excluded because of negative pulmonary CT angiography. Serum PCT values of all patients were measured and recorded before treatment was started.Results: Median values of PCT were in patients with PE 0.05 ng/ml, in patients with CAP 1.38 ng/ml. The area under ROC curve was 0.83. With an optimal cut-off value 0.27 ng/ml for differentiating PE and CAP, sensitivity was 76.4%, specificity 85.2%, negative predictive value 76.7%, positive predictive value 85.2%, and accuracy 80.7%.Conclusion: Serum PCT has a high diagnostic value in the differential diagnosis of PE and CAP. Serum PCT can be used in differentiating CAP and PE as an inflammatory marker.