Roles of serum procalcitonin in the diagnosis and severity evaluation of pneumonia in adult patients

Objective:To evaluate the usefulness of serum procalcitonin(PCT) level as a predictor of diagnosis in adult patients with pneumonia and to discuss the value of PCT in the severity assessment of pneumonia.Methods: It is a prospective study,in the 51 patients with pneumonia were enrolled in this trial.Patients' data were collected,including basic information,associated diseases,imaging examination,microbiology,blood gases analysis,and CURB-65 Score(respiratory rate,blood pressure,renal function,consciousness,age).Meanwhile,the values of PCT,CRP and WBC,IL-6,endotoxin were detected within the first 24h of admission.Results: 1.The level of PCT of the group with positive sputum culture was higher than that of mycoplasma or chlamydia pneumonia group,the varies had statistics significant between the two groups(P=0.006),it is also higher than that of the patients without etiology(P=0.004).However,the levels of WBC、CRP、IL-6 and endotoxin among the groups had no significant differences(P0.05).2.Patients with complications had a higher PCT level than those who did not.Pneumonia Severity Classification(CURB-65 Score) is an objective standard for estimating the severity of condition of pneumonia.According to this score,with 2 scores as critical value,patients was divided into two groups,using 0.1ug/L as critical values,the values of PCT were divided into two groups,significant difference was observed between mortality low group and mortality intermediate or high group(P=0.026).Conclusion: PCT may have a role to predict the etiological diagnosis in patients with pneumonia and have an advantage over CRP、endotoxin、 WBC and IL-6.The study also suggests that PCT may have a role to predict the severity in the patients with pneumonia.