Specificity of Lytic Factors for Erythrocytes, Leukocytes and Platelets in a Case of Pancytopenia

A case of chronic idiopathic pancytopenia in a young girl is presented, in which the pancytopenia was shown to be due to increased destructions of all 3 blood cell types. Antileukocyte and antiplatelet antibodies were demonstrated by transfusion methods as well as by in vitro agglutination, while differential agglutination provided evidence of a plasma factor causing increased red cell destruction.

Cross absorption experiments demonstrated the presence in the patient’s serum of at least 2 separate and distinct antibodies, specific for leukocytes and platelets respectively.

Observations on the phagocytic behavior of leukocytes and on the electrophoretic mobility of leukocytes and platelets exposed to the patient’s serum are reported.