Two Cases of Kidney Transplant Recipients With Multiple Relapsing Pure Red Cell Aplasia Due to Parvovirus B19 Infection.

Although anemia is common after kidney transplant, pure erythroid aplasia due to parvovirus B19 infection is rare. Therefore, there are delays in diagnosis in transplant patients. Here, we aimed to raise awareness that pure red blood cell aplasia due to parvovirus B19 should be considered in the differential diagnosis of posttransplant anemia. Our report analyzes 2 kidney transplant recipients under immunosuppressive therapy who were diagnosed with pure red blood cell aplasia due to parvovirus B19 infection. Both patients were examined for anemia as a cause for transfusion dependence. Normochromic, normocytic anemia, and reticulocyte levels were low. Leukocyte and platelet counts and biochemical parameters were within reference ranges.Therefore, pure red blood cell aplasia associated with parvovirus B19 was included in the differential diagnosis. Bone marrow showed erythroid hypoplasia and megaloblastic changes with giant erythroblasts containing dark-stained inclusion structures. Results from the other series (neutrophils, lymphocytes, platelets) were within reference ranges. Parvovirus B19 immunoglobulin M and G levels were negative inbothpatients, yet serum parvovirus B19 DNA polymerase chain reaction test results were positive. Therefore, diagnosis was parvovirus B19-associated pure red blood cell aplasia. Anemia resolved completely by 4 weeks after reduction of immunosuppression and intravenous immunoglobulin. Both patients relapsed in month 5 of treatment. One patient relapsed 3 times during follow-up, with complete response to intravenous immunoglobulin for all 3 events.The second patient showed partial response to intravenous immunoglobulin after relapse. We suggest that pure red blood cell aplasia associated with parvovirus B19 should be considered in transplant patients who present with anemia and reticulocytopenia. Negative serology does not exclude thediagnosis, anditis important to perform a parvovirus B19 DNA polymerase chain reaction test. Intravenous immunoglobulin therapy is effective to cure anemia within weeks. Follow-up of patients is important because relapse may occur after treatment.