ALB and susceptibility to pneumonia measurement: The strength of the present study is that CURB-65, including confusion, blood urea nitrogen, respiratory rate, and blood pressure, which are used for measuring severity of pneumonia, can be influenced by concomitant illness or other medications due to chronic disease, thus concomitant measurement of PCT and Alb, as well as establishment of consolidated scoring tool (cCURB-65) can be valuable in evaluating the severity of infectious disease and in improving prognostic accuracy.