Laboratory investigation of reactive plasmacytosis in patients with severe fever with throbocytopenia syndrome / 中华传染病杂志

ABSTRACT

Objective To investigate the immunological characteristics and clinical significance of reactive plasmacytosis in patients with severe fever with throbocytopenia syndrome (SFTS).Methods Bunyavirus-infected patients who were diagnosed with SFTS were collected from March 2015 to October 2015 in Taizhou Hospital.Morphology analysis of bone marrow and peripheral blood (PB) smear, as well as flow cytometry analysis of plasma cell immune phenotype from peripheral blood were conducted.Serum immunoglobulin levels and helper T hymphocytes (Th)1/Th2 cytokine expressions were detected.Mann-Whitney U test was used.Results PB plasma cells from all of the SFTS patients increased in varying degrees, and the phenotype of the plasma cells was CD19+CD38++CD45+CD138+, which indicated normal mature plasma cells.The ratio of PB plasma cells was >0.030 in 10/16 patients, and >0.300 in 2/16 patients.The ratios of PB plasma cells in the patients with severe and critical groups were significantly higher than that in the mild group (0.052 vs 0.016, P0.05).The serum IgG, IgA and IgM levels did not increase in acute stage, with the median of 11.6 g/L, 2.56 g/L and 1.60 g/L (reference value 0.46 to 3.04 g/L), respectively.Conclusion The patients with SFTS show excessive humoral and cellular immunity, and the severity of disease is positively correlated with the ratio of peripheral plasma cells and the levels of cytokines IL-6 and IL-10.