Autoimmune disorders of erythropoiesis

Immune-mediated disorders of erythropoiesis can result in acquired severe a nemia, low reticulocyte counts, and bone marrow exhibiting pure red cell ap lasia or ineffective erythropoiesis. Erythropoiesis can be suppressed or im paired by humoral or cellular mechanisms. In vitro inhibition of erythroid colony growth by immunoglobulins or lymphocytes can be a strong argument fo r the immune origin of the disease. Classical etiologies are thymoma and he matologic malignancies such as chronic lymphocytic leukemia (CLL). Clonal p roliferation of T cells has been incriminated. Recently, acquired circulati ng autoantibodies directed against erythropoietin have been detected in a c ase of pure red cell aplasia. Autoimmune mechanisms have also been detected or suggested in synartesis and in Fas-associated dyserythropoiesis, two di stinct syndromes recently described where morphologic abnormalities specifi c to the erythroid lineage illustrate ineffective erythropoiesis. (C) 2001 Lippincott Williams & Wilkins. Inc.