摘要BACKGROUND:Heatstroke has become a common emergency event in hospitals.Procalcitonin(PCT)is used as a biomarker of infection in the emergency department(ED),but its role in rhabdomyolysis(RM)following exertional heatstroke(EHS)remains unclear.METHODS:A retrospective cohort study enrolled patients with EHS from the intensive care unit(ICU).We collected RM biomarkers,infiammation markers,critical disease scores at admission,24 h,48 h,and discharge,and 90-day mortality.Correlation analysis,linear regression and curve fitting were used to identify the relationship between PCT and RM.RESULTS:A total of 162 patients were recruited and divided into RM(n=56)and non-RM(n=106)groups.PCT was positively correlated with myoglobin(Mb),acute hepatic injury,disseminated intravascular coagulation(DIC),Sequential Organ Failure Assessment(SOFA)score,and Acute Physiology and Chronic Health Evaluation Ⅱ(APACHE Ⅱ)score,with correlation coefficients of 0.214,0.237,0.285,0.454,and 0.368,respectively(all P＜0.05).Interestingly,the results of curve fitting revealed a nonlinear relationship between PCT and RM,and a two-piecewise linear regression model showed that PCT was related to RM with an odds ratio of 1.3 and a cut-off of＜4.6 ng/mL.Survival analysis revealed that RM was associated with higher mortality compared to non-RM cases(P=0.0093).CONCLUSION:High serum PCT concentrations are associated with RM after EHS in critically ill patients.Elevated PCT concentrations should be interpreted cautiously in patients with EHS in the ED.