Role of severe fever with thrombocytopenia syndrome (SFTS) critical score in predicting the prognosis for SFTS patients

Abstract

Objective To investigate of the risk factors for the death of severe fever with thrombocytopenia syndrome (SFTS), so as to set up SFTS critical score and evaluate its role in predicting the prognosis for patients with SFTS. Methods A total of 123 SFTS patients hospitalized in Ji′nan Hospital of Infectious Diseases affiliated to Shandong University from June 2011 to October 2014 were enrolled in this study. The univariate Logistic regression analysis was performed to analysis the risk factor for the death of SFTS. Then the SFTS critical score system was set up accordingly. The prognosis value of SFTS critical score was compared with the rapid emergency medicine score (REMS) and the acute physiology and chronic health evaluation Ⅱ (APACHEⅡ) by using receiver operator characteristic curve (ROC). Results Among all the patients, 17 males and 14 females were in death group, and 45 males and 47 females were in survival group. The results of the univariate Logistic regression analyses indicated that the glasgow coma scale (GCS), lactate dehydrogenase, activated partial thromboplastin time, oxygen saturation were risk factors for the death of SFTS, with statistically significant difference (all P<0.05). All of the four parameters of SFTS critical scores in the death group were higher than those in the survival group, with statistically significant difference (all P<0.05). The REMS, APACHEⅡ score and SFTS critical score in the death group were significantly higher than those in the survival group (all P<0.01). The area under the curve (AUC) of REMS, APACHEⅡ scores and SFTS critical score were 0.734, 0.746 and 0.788, respectively. The Youden index of the SFTS critical scores was the highest among all three scores (P<0.01). If 15.0 was used as the cut off value of SFTS critical score, the specificity and the sensitivity for predicting the death risk for the hospitalized patient were 74.2% and 76.1%, respectively. Conclusion SFTS critical score, REMS and APACHEⅡ score can all effectively predict the prognosis for SFTS patients, among which, the SFTS critical score is the most convenient and has the best predictive value. Key words: Severe fever with thrombocytopenia syndrome; Critical score; REMS; APACHE; Receiver operating characteristic curve; Logistic models