Abstract
Background
It is difficult but important to differentiate between bacterial and viral infections, especially for respiratory infections. Hence, there is an ongoing need for sensitive and specific markers of bacterial infections. We investigated novel biomarkers for discriminating community acquired bacterial pneumonia from 2009 H1N1 influenza A infections.
Methods
This was a prospective, observational study of patients with community acquired bacterial pneumonia, 2009 H1N1 Influenza A infection, and healthy controls. Serum samples were obtained on the initial visit to the hospital and stored at -80℃. We evaluated CRP (C-reactive protein), PCT (procalcitonin), LBP (lipopolysaccharide-binding protein) and copeptin. These analytes were all evaluated retrospectively except CRP. Receiver operating characteristic curve (ROC) analyses were performed on the resulting data.
Results
Enrolled patients included 27 with community acquired bacterial pneumonia, 20 with 2009 H1N1 Influenza A infection, and 26 who were healthy controls. In an ROC analysis for discriminating community acquired bacterial pneumonia from 2009 H1N1 influenza A infection, areas under the curve (AUCs) were 0.799 for CRP (95% Confidence interval [CI], 0.664~0.934), 0.753 for PCT (95% CI, 0.613~0.892) and 0.684 for LBP (95% CI, 0.531~0.837). Copeptin was not different among the three groups.
Figures and Tables
Table 1
Values are presented as number (%) unless otherwise indicated. Kruskall-Wallis test (in age) and chi-square test (in other variables) were used for p-values.
*p=0.001 by Mann-Whiynet U test between bacterial pneumonia and 2009 Influenza A H1N1, †p=0.018 by Fisher's exact test between bacterial pneumonia and 2009 Influenza A H1N1, ‡p=0.013 by Fisher's exact test between bacterial pneumonia and control.
NS: non-specific.
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