Immune Thrombocyt openia in Lymphoproliferative Disorders

Lymphoproliferative disorders (LPDs) are recognized as a common cause of secondary ITP. Approximately 30% of secondary ITP cases are present on diagnosis of lymphoid tumors or develop during the course of the disease. 2,3 Among the different LPDs, ITP has the highest prevalence in chronic lymphocytic leukemia (CLL), 4 ranging between 2% and 5%. 5–8 It is far less frequent in non-Hodgkin lymphoma and Hodgkin lymphoma (HL), where its prevalence is invariably reported to be below 2%. 4,9–14 Because of its rarity, the clinical behavior and response to treatment of secondary ITP in LPDs has been poorly investigated. A correlation between the survival of patients with LPDs and the occurrence of autoimmune phenomena directed against hematopoietic cells has been observed 4 but not confirmed. 12 Diagnosis of ITP associated with LPDs may be difficult at times, given that many confounding events are known to variably reduce the platelet count in addition to diffuse bone marrow infiltration by malignant lymphocytes. Moreover, reversible thrombocytopenia may be induced by the toxic effects of chemotherapy. The lack of sufficient sensitivity and specificity of platelet autoantibody tests (which parallel the direct Coomb test for