Clinical Significance Of Peripheral Blood Lymphocyte Subsets In Children With Immune Thrombocytopenia

Objective: Immune thrombocytopenia(ITP)is a hemorrhagic disease with abnormal cellular and humoral immunity.It is characterized by simple thrombocytopenia and may have clinical manifestations such as skin,mucous membrane or visceral spontaneous bleeding.The purpose of this study was to explore the correlation between lymphocyte subsets and disease severity in children with ITP and its value in predicting the curative effect.We will retrospectively analyze the characteristics of lymphocyte subsets in children with ITP and their correlation with platelet count,bleeding scale and treatment response,so as to provide immunological basis for clinical diagnosis and treatment.Method: The subject were 78 children with newly diagnosed immune thrombocytopenia who were hospitalized in the Pediatrics Hematology Department of Quanzhou Children’s Hospital from March 2015 to February 2020.The levels of CD3+ cells,CD3+CD4+ cells,CD3+CD8+ cells,CD4+/CD8+ratio,CD19+ cells and CD16+CD56+ cells in peripheral blood of all subjects were measured by flow cytometry,platelet count and bleeding scale was recorded at the same time.Patients with ITP were treated with first-line treatment,and the treatment response was evaluated after 8 weeks.All statistical analyses were conducted using SPSS version 26.Normal distribution is expressed by mean and standard deviation,otherwise by median and quartile.The differences of CD3+ cells,CD3+CD4+ cells,CD3+CD8+ cells,CD4+/CD8+ ratio,CD19+ cells and CD16+CD56+ cells were statistically tested.T-test and Mann-Whitney test were used for data fulfilled normal distribution and for those did not,respectively.Multiple linear regression analysis was used to observe the effect of lymphocyte subsets on platelet count in children with ITP.The correlation between lymphocyte subsets and bleeding scale,treatment effectiveness,onset time and complete reaction time were observed.Pearson correlation analysis and Spearman correlation analysis were used for data fulfilled normal distribution and for those did not,respectively.P values less than 0.05 were considered statistically significant for all tests.Result: 1.78 children with ITP were included,ranging in age from 1month to 9 years,with an average age of(2.12 ±2.05)years.there were 52 males and 26 females.Platelet counts ranged from(2-52)×109/L with a median of 14×109/L.72 cases were effective,the range of onset time was(1-7)days,the median was 2 days,the average complete reaction time was(5.33±1.92)days,2 cases were steroid dependent and 4 cases were ineffective.2.There was no significant difference in the level of CD3+ cells between the ITP group and the control group,but the levels of CD3+CD4+ cells,CD4+/CD8+ ratio and CD16+CD56+ cells in ITP group were lower than in controls,while the levels of CD3+CD8+ and CD19+ cells in ITP group were higher.3.CD19+ cell level has an effect on platelet count.There is a linear regression relationship between CD19+ cell level and platelet count,and there is a negative correlation between them(β=-0.652,P<0.01).The bleeding scale was positively correlated with the level of CD19+ cells(r = 0.30).There was no correlation between the bleeding scale and the level of CD3+CD8+ cells,CD3+CD4+ cells,CD4+/CD8+ ratio and CD16+CD56+ cells(P > 0.05).4.(1)There was no correlation between the efficacy of treatment and the level of CD3+CD8+ cells,CD3+CD4+ cells,CD4+/CD8+ ratio,CD19+ cells and CD16+CD56+ cells(P >0.05).(2)The onset time was positively correlated with the level of CD3+CD8+ cells(r = 0.35),and it was negatively correlated with CD4+/CD8+ ratio(r =-0.29)and CD19+ cells(r =-0.38).(3)There was no correlation between complete reaction time and the level of CD3+CD8+cells,CD3+CD4+ cells,CD4+/CD8+ ratio,CD19+ cells and CD16+CD56+cells(P>0.05).Outcome: 1.The proportion of lymphocyte subsets in children with ITP is out of balance,with higher levels of CD3+CD8+ cells and CD19+ cells,and lower levels of CD3+CD4+ cells,CD4+/CD8+ ratio and CD16+CD56+cells,which may be involved in the occurrence and development of ITP.2.The level of CD19+ cells is negatively correlated with platelet count,and is positively correlated with bleeding scale in children with ITP,which can be used to assessing the severity of the disease.3.There is no correlation between the level of peripheral blood lymphocyte subsets and the response after treatment in children with ITP,but it is related to the speed of onset.IVIG may be more suitable for treatment with high level of CD8+ cells,CD4/CD8+ ratio or low level of CD19+ cells.