The characteristics of laboratory analysis for primary immunodeficiency diseases in children

Objective To characterized the laboratory analyses in primary immunodeficiency diseases(PID)in children,to provide better approach to early diagnosis.Methods Cellular and humoral immune functions were measured among 76 patients with PID.Results In aspects of humoral immune function tests,the level of IgG was lower in patients with common variable immunodeficiency(CVID)or severe combined immunodeficiency disease(SCID),especially in patients with CVID accompanying by low level of IgA and decreased count of CD19+ B cells.Low level of IgA were also observed in patients with CVID,selective IgA deficiency or AT.Patients with hypogammaglobulinemia had low level of IgG,IgA and decreased count of CD19+B cells.In aspects of cellular immune function,decreased count of CD3+ and CD4+ T was seen in SCID and DGS.Low ratio of CD4+/CD8+ was found in AT.The subset of T cells and activation cell marker in T cells were evaluated in eight patients with CVID,among whom five patients had inversed CD4+/CD8+ ratio(CD4+/CD8+ 0.9).Furthermore,the percentage of CD4+HLA-DR+ and CD8+CD45RO+ T cells in patients with CVID were higher than normal control while the percentage of CD4+CD45RA+ T was lower than normal control(P 0.01).Conclusions Different kind of PID showed different laboratory characteristics.Over-activation of T cells may be a cause of autoimmune disorder in CVID.