Study On The Prognostic Factors Of Fever With Thrombocytopenia Syndrome And The Establishment Of Predictive Scoring Model

Objective: Severe fever of thrombocytopenic syndrome(SFTS)is an emerging epidemic disease caused by SFTS virus(SFTSV)with an estimated mortality rate of 6% to 30%.Currently,the disease has been reported in China,Japan,South Korea and the United States.However,there is no specific antiviral treatment for SFTSV infection.Because of the high mortality of SFTS and the rapid evolution of disease,it is important to provide appropriate treatment for SFTS patients as soon.as possible.Therefore,it is important for clinicians to predict these SFTS cases that are more likely to have a poor prognosis or even death.In this study,we established a simple and feasible model for assessing the prognosis of patients with SFTS.The model can help doctors identify patients with poor prognosis and give strong symptomatic supportive treatment as soon as possible to prevent rapid disease progression and reduce death in SFTS patients.Method: The basic information,epidemiological data,laboratory findings,Clinical symptoms,previous history and complications of patients diagnosed with SFTS at the Department of Infectious Diseases,Union Hospital of Tongji Medical College,Huazhong University of Science and Technology from January 20 to December 2019,were collected by retrospective study..;retrospective comparison of death and nondeath patients,analysis of factors associated with disease severity and prognosis in patients with SFTS.Results: By comparing the data of death group and non-death group,the mortality rate of patients was 9.43%,and the average time from disease onset to death in death group was 12.4 days.The study found that factor closely related to poor prognosis were: age,dizziness,Bleeding symptoms,Hemophagocytic syndrome,neutrophil percentage,percentage of monocytes,Aspartate aminotransferase values,albumin,lactate Dehydrogenase values,SFTSV quantification,creatinine,urea nitrogen,PT,pulmonary bacterial infection,D dimer,ferritin and nervous system symptoms.The above indicators were used as independent variables,and the patient’s prognosis was used as a dependent variable for regression analysis.A total of six indicators were included in the equation: age,bleeding performance,percentage of neutrophils,LDH,PT,neurological symptoms.The predictive equation for the risk associated with death is:(Death probability)=-26.016+0.081×age+0.001×LDH+0.718×PT+1.562×bleeding performance+2.126×neuropathy symptoms+0.081×neutrophil%.Conclusion: Severe Fever with thrombocytopenia syndrome progresses rapidly,and severe patients often die within two weeks of onset.Among all prognostic factors,the percentage of neutrophils,LDH and PT had the most significant effect on prognosis,and the prognosis of patients with Bleeding symptoms and neurological symptoms was worse than those without neurological symptoms.Age,bleeding performance,dizziness,percentage of neutrophils,LDH,PT,neurological symptoms.It is closely related to the prognosis of patients.This study has certain limitations.First,it is a singlecenter retrospective study rather than a multi-center prospective study.Second,the sample size is limited and the number of cases needs to be increased.Third,there are subjective symptoms such as dizziness in the prediction equation,which is not conducive to doctors.Judgment;Fourth,the prediction model will be further refined and validated to serve the clinical.