CRP and viral pneumonia: The median serum procalcitonin concentration was also higher in the bacterial pneumonia group than in the viral pneumonia group (1.9 ng/ml vs. 0.3 ng/ml, P = 0.02), and the C-reactive protein concentration tended to be higher in the bacterial pneumonia group than in the viral pneumonia group (20.3 mg/dL vs. 14.9 mg/dL, P = 0.09).