Comparative immunological studies in ITP.

Twelve splenectomized and 16 non-splenectomized patients with ITP were studied for autoimmune complement fixation (AICF), indirect immunofluorescence (IF), platelet "immuno-injury" (T-3), antinuclear antibody (ANA), and serum electrophoresis. AICF was found positive in 50%, IF in 81%, T-3 in 50%, ANA in 69% of splenectomized cases. No significant difference in any of above parameters or in the gamma globulin levels was found between the splenectomized and the non-splenectomized groups. These observations are less favourable than those reported by other workers in post-splenectomy cases of ITP. The results, in agreement with those of earlier lymphocyte-transformation studies of the authors, are consistent with the primary mechanical role of the spleen in ITP, and make it justified to connect the failure of ITP to respond adequately to splenectomy, and the persistent seropositivity in these cases, with an excessive IgG production by the bone marrow.