Abstract: Objective To assess the clinical value of serum propionic acid at diagnosis and mortality predicts in patients with septic shock. Methods From March 2015 to December 2017, a total of one hundred and forty-nine septic patients as well as fifty healthy volunteers were enrolled in this study. Septic patients were divided into septic shock group and non-septic shock group. Univariate analyses for the differece of clinical data, multivariate logistic regression analysis was employed to further identify the independent predictors of mortality and septic shock. Receiver operating characteristics (ROC) curves was used to evaluate prognostic and mortality of the biomarkers predicted sepsis shock. Survival rate of different PA concentration were performed by Kaplan-Meier method. Results Respiratory rate, heart rate, PA, CRP, PCT, LA, WBC were significantly higher in both septic shock group and non-septic shock group than control group. Meanwhile, MAP, PA, CRP, PCT, LA, APACHEⅡ score, SOFA score, 30 d mortality and 90 d mortality were significantly higher in septic shock group than non-septic shock group, the differences between two groups were statistically significant (P<0.05). Multivariate logistic regression analysis showed that age, PA, PCT, APACHEⅡ score was independent factor of sepsis shock. Besides, low levels of MAP and high serum PA was independent factor of sepsis shock 30 d mortality and 90 d mortality (P<0.05). Correlation analysis showed that serum PA was positive correlation to PA, PCT and APACHEⅡ score (P<0.05). The ROC analysis showed the AUC of PA for predicting septic shock were 0.912, with cut-off 10.95 μg/L, with sensitivity and specificity was 90.1% and 77.6%, respectively. Using a PA cut-off of 12.52 μg/L for predicting septic shock 30 d mortality and 90 d-mortality, the sensitivity was 75.9% and 70.6%, the specificity was 70.5% and 74.1%, respectively. Log-rank survival analysis showed that 30 d survival and 90 d survival was significantly higher in low PA concentration group than high PA concentration group (P<0.05). Conclusion Propionic acid is markedly increased in septic shock patient, it can be used as a parameter for diagnostic and prognostic of septic shock.

Key words: Septic shock, Propionic acid, Serum, Diagnosis, Prognosis