Abstract
Chronic idiopathic thrombocytopenic purpura (c-ITP) is an autoimmune disorder, but the abnormalities in immune mechanism have remained only vaguely defined. In this study, we examined the correlation among the platelet counts, platelet associated immunoglobulin G (PAIgG), platelet associated immunoglobulin M (PAIgM), platelet volume, various immunological functions and severity of illness at onset. In c-ITP patients an inverse relation ship was found between the platelet counts and PAIgG (r=-0.3648, p<0.05). The correlation was found between PAIgG and PAIgM (r=0.6055, p<0.001). And in c-ITP patients an inverse relationship was also found between the platelet counts and PAIgM (r=-0.3456, p<0.05). In c-ITP the proportion of CD 3 and CD 8 were significantly decreased (p<0.05) compared with controls. But there were no difference in proportion of CD 4 and CD 4/8 ratio. There was no difference in lymphocytic blastogenic response to phytohemagglutinin (PHA). Stimulation index of concanavalin A for patients' lymphocytes were significantly decreased compared with controls' lymphocytes. The proportion of T-cells was no different than those of control. But the proportion of B-cell was a significantly increased (p<0.05) compared with controls. There were no correlation among clinical severity of illness at onset and immunological functions, platelet antibodies and platelet volumes. These data suggested that the abnormalities of T-cell subset and the proportion of B-cell in peripheral blood may play an important role in outbreak of c-ITP in childhood.
