Autoimmune Cytopenias: Diagnosis & Management

The autoimmune cytopenias are a related group of disorders in which differentiated hematopoietic cells are destroyed by the immune system. Single lineage disease is characterized by the production of autoantibodies against red cells (autoimmune hemolytic anemia [AIHA]), platelets (autoimmune thrombocytopenia [ITP]) and neutrophils (autoimmune neutropenia [AIN]) whereas multilineage disease may include various combinations of these conditions. Central to the genesis of this disease is the breakdown of central and/or peripheral tolerance, and the subsequent production of autoantibodies by both tissue and circulating self-reactive B lymphocytes with support from T helper lymphocytes. These disorders are classified as primary (idiopathic) or secondary, the latter associated with an underlying malignancy, systemic autoimmune disease, infectious disease or a specific drug. Non-specific immunosuppression with corticosteroids remains the first-line therapy for many of these disorders, and although associated with high response rates, is compromised by significant toxicity and high relapse rates. Management of patients with chronic refractory autoimmune cytopenias who have failed first-line and second-line (cytotoxic immunosuppressant therapy and or splenectomy) is particularly complex, with definitive treatment in select patients requiring hematopoietic stem cell transplantation. Given the toxicity concerns of non-selective immunosuppressants, development of therapeutic regimens that avoid steroids has progressed rapidly in recent decades. [Full article available at http://rimed.org/rimedicaljournal-2016-12.asp].