See also: Anemia: General Considerations.
Definition and EtiologyTop
Pure red cell aplasia (PRCA) refers to aplasia of the erythroid lineage leading to severe normocytic (in some cases macrocytic) and normochromic anemia. It may be inherited (Diamond-Blackfan syndrome) or acquired. In the latter case, it develops due to viral infections (parvovirus B19, Epstein-Barr virus, hepatotropic viruses), immunologic disorders (thymoma, myasthenia gravis, systemic lupus erythematosus, rheumatoid arthritis), chronic lymphocytic leukemia, treatment with an erythropoiesis-stimulating agent (ESA), or drugs (phenytoin, carbamazepine, valproate, azathioprine, chloramphenicol, sulfonamides, isoniazid). PRCA may precede myelodysplastic syndrome.
The diagnosis of PRCA is usually made in patients >40 years. Clinical features include severe anemia with low reticulocyte counts, normal serum erythropoietin levels, and low bone marrow erythroblast counts (<0.5%). Clinical subtypes include acute transient PRCA (caused by viral infections or drugs) and chronic PRCA (thymoma, systemic lupus erythematosus, rheumatoid arthritis).
Successful treatment of the underlying condition (eg, withdrawal of the ESA) frequently leads to the resolution of PRCA. In other cases, immunosuppressive treatment is used (most frequently with glucocorticoids; in steroid-resistant patients, cyclosporine [INN ciclosporin], antilymphocyte globulin, cyclophosphamide, high-dose intravenous immunoglobulin, rituximab, and alemtuzumab are used). Patients requiring frequent packed red blood cell transfusions may develop iron overload.