[Diagnosis and management of pure red cell aplasia]

Pure red cell aplasia (PRCA) is a type of bone marrow failure syndrome (stem cell failure) and is characterized by severe normocytic, normochromic anemia associated with reticulocytopenia, and the absence of erythroblasts in otherwise normal bone marrow. PRCA may be congenital or acquired, and the acquired form of chronic PRCA may present as a primary hematological disease in the absence of any other diseases or secondary to thymoma, lymphoproliferative disorders, infections, and collagen vascular diseases or after exposure to various drugs or chemicals. The most common types of acquired chronic PRCA in Japan are idiopathic, thymoma-associated and lymphoid neoplasm-associated PRCA. Initial treatment of PRCA includes the cessation of potentially deleterious drugs and careful observation for one month while making efforts to identify the cause of PRCA. Idiopathic PRCA and secondary PRCA refractory to treatment of the underlying diseases are generally treated as immune-mediated disorders. Most chronic PRCA patients successfully treated with immunosuppressants require maintenance immunosuppressive therapy. Thus, identifying the cause of PRCA is crucial for the optimal management of this disorder.