Parvovirus B19 infection after plasma exchange for myasthenia gravis.

We describe a case of pure red cell aplasia caused by a B19 parvovirus infection in a female myasthenic patient treated with plasma exchange, corticosteroids, and cholinesterase inhibitors. Two weeks after albumin infusion, she developed anemia with an absence of reticulocytes. A bone marrow aspirate was performed, showing a markedly hypoplastic erythroid series with numerous giant pronormoblasts. Anemia with severe reticulocytopenia and morphology of bone marrow suggested a diagnosis of pure erythroblastopenia due to parvovirus B19 infection, which was confirmed by positive immunoglobulin (Ig)M] and IgG anti-B19 virus. The patient successfully responded to IVIG treatment with a complete remission. In this case, we could not confirm whether an albumin-derived infection combined with a concomitant immunocompromised condition due to myasthenia and immunosuppressive treatment was responsible for the disease. Although human B19 DNA content does not reflect infectivity, it is not possible to exclude that blood derivates, such as albumin, clot factors, and immune globulin may be infectious. Actually, blood component B19 infection is still an unresolved problem. Many strategies such as new methods for viral inactivation and discarding positive B19 units may help to increase blood product safety.