The value of procalcitonin level in community-acquired pneumonia in the ED

Objectives: The aim of this study was to investigate the value of procalcitonin (PCT) level in patients with community-acquired pneumonia (CAP) in the emergency department (ED). Methods: We conducted a prospective study of patients with CAP in the ED. Patients presenting with a clinical and radiographic diagnosis of CAP were enrolled. The authors measured inflammatory biomarkers. The severity of CAP was assessed by 3 prediction rules. We performed an analysis to assess the value of each biomarker for the prediction of mortality and CAP severity. Results: A total of 126 patients with CAP are included. Sixteen patients who were older and belonged to high-risk group died within 28 days. Nonsurvivors had significantly increased median PCT level (1.96 vs 0.18 ng/mL) and high-sensitivity C-reactive protein (158.57 vs 91.28 mg/dL) compared with survivors. The median PCT levels were significantly higher in more severe disease, on 3 prediction rules. In regression logistic analyses, the area under the receiver operating characteristic curve of PCT level were 0.828 (95% confidence interval, 0.750-0.889). The addition of PCT level to three prediction rules significantly increased the area under the receiver operating characteristic curve. These results suggest that PCT measurement is more versatile tool for predicting mortality and the severity of disease among patients with CAP in the ED. Conclusions: Procalcitonin level is valuable for predicting mortality and the severity of disease among patients with CAP at ED admission. Procalcitonin level as an adjunct to CAP prediction rules may be valuable for prognosis and severity assessment.