Prognostic value of natural killer cell count combined with P-selectin in primary thrombocytopenic purpura

YANG Xiaofei; WANG Jing

doi:10.11786/sypfbxzz.1674-1293.20250302

Abstract：Objective To analyze the significance of peripheral blood natural killer(NK)cell count and P-selectin(CD62P)levels in idiopathic thrombocytopenic purpura(ITP)and their predictive value for prognosis.Methods A total of 118 children with ITP admitted to the Second Affiliated Hospital of Air Force Medical University between February 2022 and February 2024 were enrolled in the ITP group,and 50 healthy individuals undergoing routine physical examinations during the same period were included in the healthy control group.Flow cytometry was used to count peripheral blood NK cells and CD62P-positive cells in both groups.Logistic multivariate regression analysis was performed to identify factors influencing the prognosis of children with ITP.Receiver operating characteristic(ROC)curve analysis was conducted to calculate the area under the curve(AUC)and evaluate the predictive value of peripheral blood NK cell count and CD62P levels for ITP prognosis.Results The ITP group showed significantly lower peripheral blood NK cell counts(P<0.05)and higher CD62P levels(P<0.05)compared with the healthy control group.In the good prognosis subgroup,the proportions of factors such as older age at onset(>3 years)and family history of allergy were lower than those in the poor prognosis subgroup(P<0.05),while the proportions of glucocorticoid and immunoglobulin therapy were higher(P<0.05).The disease course and platelet recovery time were significantly shorter in the good prognosis subgroup(P<0.001),with higher pre-treatment white blood cell counts and NK cell counts(P<0.001),and lower pre-treatment IgE and CD62P levels(P<0.001).Logistic regression analysis revealed that glucocorticoid,immunoglobulin,peripheral blood NK cell count,and CD62P levels were independent influencing factors for ITP prognosis(P<0.05),among which glucocorticoid and immunoglobulin were protective factors(P<0.05),while decreased NK cell count and increased CD62P were risk factors(P<0.05).ROC curve analysis showed that the combination of peripheral blood NK cells and CD62P had higher specificity,accuracy,positive predictive value,and AUC for predicting poor prognosis in ITP children compared with single marker detection.Conclusion Reduced peripheral blood NK cell count and increased CD62P expression are independent risk factors for poor prognosis in children with ITP.Combined detection of these two markers demonstrates high value in predicting poor prognosis in ITP children.