To analyze the level of serum procalcitonin (PCT) in severe burn patients during shock period, and to evaluate its clinical significance.

This was a retrospective cohort study of total 201 severe burn patients admitted to Department of Burns and Plastic Surgery, First Hospital Affiliated to the Chinese People′s Liberation Army General Hospital from January 2014 to January 2017. The basic data of patients′ age, gender, cause of injury, area of burn and prognosis were collected, and the laboratory examination results of serum PCT, routine blood test, liver and kidney function and blood gas analysis were recorded during shock period. Spearman rank correlation were used to analyze the relationship between PCT level and clinical parameters. The difference of PCT level between survivors and non-survivors was evaluated among the subgroups divided by burn size. Data were processed with t test and Mann-Whitney U test. Receiver operating characteristic(ROC) curve analysis was performed to evaluate the diagnostic value of PCT level for predicting mortality in burn patients. The Kaplan-Meier method and Log bank test were used for survival analysis.

There were significant correlations between leucocyte count(r=0.350, P<0.01), blood glucose (r=0.258, P<0.01), creatinine(r=0.284, P<0.01), urea nitrogen(r=0.216, P<0.01), total bilirubin (r=0.372, P<0.01), sequential organ failure assessment (SOFA) score(r=0.681, P<0.01), albumin (r=-0.154, P=0.029), brain natriuretic peptide(r=0.151, P=0.032), oxygenation index(r=0.173, P=0.014), burn index(r=0.693, P<0.01) and PCT level during shock period. Only 1 patient died of burn index less than 60. The area under the ROC curve of PCT level for predicting death for 54 patients with burn index more than 60 was 0.844(95%CI 0.637-0.927, P<0.01), and the best threshold value was 2.394 ng/mL, with sensitivity of 85.0% and specificity of 79.4%. Survival analysis revealed that the survival rates were 90% and 29%, after 90 days in the patients with PCT levels ≤ 2.394 ng/mL and in those with>2.394 ng/mL, respectively(Log-rank=23.95, P<0.01).

PCT level during shock period can be a useful biomarker for predicting severity and prognosis in severe burn patients.