IL-10 polymorphisms and T-cell subsets could affect the clinical presentation and outcome of childhood immune thrombocytopenia in Egyptian population

The aim is to study IL-10 polymorphisms and IL-10 level and assess their relation to T-cell subsets in childhood immune thrombocytopenia (ITP). In all, 40 (25 acute, 15 chronic) ITP child patients were investigated at time of presentation, compared to 15 healthy, age- and gender-matched controls and followed up for 1 year to determine chronic cases. Studying the effect of IL-10 promoter polymorphism was done by PCR-RFLP, IL-10 level was determined by ELISA, natural killer cells and T-cell subsets were evaluated by flow cytometry. Subjects with IL-10 promoter (1082 AA and 592 AA) genotypes had lower IL-10 levels and had lower CD4%, higher CD8%, lower CD4/CD8 ratio and lower T-reg%. IL-10 polymorphisms had no effect on NK%. IL-10 serum levels and IL-10 promoter polymorphic genotype frequencies are not different between ITP cases and controls; however, in ITP patients, IL-10 promoter (1082 AA and 592 AA) genotypes and associated lower CD4, higher CD8, lower CD4/CD8 ratio is associated with more severe thrombocytopenia at presentation and had a poorer response to first-line treatment. Patients with lower T-reg cells had a higher tendency to develop chronic ITP. IL-10 level and polymorphisms as well as disturbed T-cell subsets percentages are demonstrable effectors of immune dysfunction in ITP and can affect the presentation and outcome of childhood ITP.