title: Rheumatoid arthritis and pure red cell aplasia.
abstract: Three patients with severe, deforming, and long-standing rheumatoid arthritis developed pure red cell aplasia that did not remit after withdrawal of medications, ran a chronic course, and in two patients remitted only after cytotoxic immunosuppressive treatment. An IgG inhibitor of autologous erythroid colony-forming and burst-forming unit growth in vitro was found in the serum of one patient. This specific erythropoietic inhibitor persisted in lower titer in the patient's serum even after an azathioprine-induced remission of pure red cell aplasia, indicating the possible need for maintenance immunosuppressive therapy. Chronic pure red cell aplasia may be another extra-articular manifestation of rheumatoid arthritis and should be considered when severe anemia develops in the absence of blood loss or hemolysis.
mesh_terms: D000368:Aged; D000741:Anemia, Aplastic / Q000209:etiology* / Q000276:immunology; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000150:complications* / Q000276:immunology; D001856:Bone Marrow Examination; D003114:Colony-Forming Units Assay; D004920:Erythropoiesis; D005260:Female; D006801:Humans; D007074:Immunoglobulin G; D008875:Middle Aged
chemical_list: D007074:Immunoglobulin G