title: Dynamic changes of laboratory parameters and peripheral blood lymphocyte subsets in severe fever with thrombocytopenia syndrome patients.
abstract: OBJECTIVE
  The aim of this study was to dynamically investigate laboratory parameters and peripheral blood lymphocyte subsets in severe fever with thrombocytopenia syndrome (SFTS) patients at different stages, to evaluate the significance of these changes in the infection process and its influence on prognosis.
  
  
  METHODS
  Case-control study was used in the research. Sixty-nine confirmed thrombocytopenia syndrome virus(SFTSV) infected patients were enrolled. They were divided into two groups, recovery group and poor prognosis group, according to the clinical prognosis of the diseases. The laboratory parameters were measured by matched fully-automatic detector. The dynamic lymphocyte subsets of each group were tested by flow cytometry. Independent-group Student's t-test, Bonferroni test and Nemenyi test were used to compare the mean value of every group.
  
  
  RESULTS
  The clinical manifestations typically became worse on about the 7th day. Most of them had multi organ dysfunction, and part of them had hemophagocytic lymphohistiocytosis histiocytosis (HLH). The characteristic laboratory findings in the early stage were the drop of platelets (PLT), while the increase of alanine aminotransferase (ALT), aspartate amino transferase (AST), creatine kinase (CK), and lactate dehydrogenase (LDH). SFTSV viral loads reached the highest on Days 7-10 after onset of fever in SFTS patients. CD3+, CD3+CD4+ T cell counts were significantly reduced in poor prognosis group, more so on Days 7-10 after onset of fever. CD3-CD19+ (B cell) counts in SFTS patients were significantly higher than that of healthy controls. 11 days after illness onset, symptoms were improved, accompanied by resolution of laboratory abnormalities.
  
  
  CONCLUSIONS
  These results indicated that SFTS had an acute onset and self-limited course. It was a systemic infection. The host immune response caused tissues and organs injury. The improvement of symptoms and laboratory tests was consistent with the elimination of the virus and recover of immune response. Further investigation should be done in order to reveal the mechanisms of SFTSV pathogenesis and guide the clinical treatment.
authors.affiliation: Jinan Infectious Diseases Hospital, Jinan, Shandong 250021, China.
authors.forename: Jingwen
authors.initials: J
authors.lastname: Liu
authors.affiliation: Jinan Infectious Diseases Hospital, Jinan, Shandong 250021, China.
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.affiliation: Jinan Infectious Diseases Hospital, Jinan, Shandong 250021, China.
authors.forename: Zhaolei
authors.initials: Z
authors.lastname: Feng
authors.affiliation: Jinan Infectious Diseases Hospital, Jinan, Shandong 250021, China.
authors.forename: Daying
authors.initials: D
authors.lastname: Geng
authors.affiliation: Jinan Infectious Diseases Hospital, Jinan, Shandong 250021, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Jinan Infectious Diseases Hospital, Jinan, Shandong 250021, China; Collaborative Innovation Center for the Origin and Control of Emerging Infectious Diseases, Taishan Medical University, Taian, Shandong 271016, China. Electronic address: sdjnygy@163.com.
authors.forename: Guangying
authors.initials: G
authors.lastname: Yuan
mesh_terms: D000328:Adult; D000368:Aged; D001219:Aspartate Aminotransferases / Q000378:metabolism; D002044:Bunyaviridae Infections / Q000097:blood / Q000175:diagnosis / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D016022:Case-Control Studies; D021821:Communicable Diseases, Emerging / Q000097:blood / Q000276:immunology*; D005260:Female; D005334:Fever / Q000821:virology; D005434:Flow Cytometry; D006801:Humans; D018655:Lymphocyte Count; D016131:Lymphocyte Subsets; D008297:Male; D008875:Middle Aged; D016856:Phlebovirus / Q000276:immunology; D011379:Prognosis; D013921:Thrombocytopenia / Q000097:blood / Q000821:virology*; D019562:Viral Load
chemical_list: D001219:Aspartate Aminotransferases
keywords: Flow cytometry; Laboratory parameters; Pathogenesis; SFTSV; T lymphocyte subsets