An Immunoenzyme Histochemical Technique for the Detection of Platelet Antibodies from the Serum of Patients with Idiopathic (Autoimmune) Thrombocytopenic Purpura (ITP)

The present report describes a simple, reproducible, semi‐quantitative immunohistochemical assay for the detection of antiplatelet antibody. Evaluation of the technique in 10 children with active idiopathic (autoimmune) thrombocytopenic purpura (ITP), seven children with thrombocytopenia due to other causes, and 12 normal individuals revealed that the assay consistently and reliably distinguished children with ITP from the other groups. Individuals who had had multiple platelet transfusions and individuals with systemic lupus erythematosus (SLE) also had antiplatelet antibodies detectable using this technique although the levels were less than those of individuals with ITP. The method can be used effectively to monitor the course of ITP and the effects of therapy.