Chronic anemia due to parvovirus B19 infection in a bone marrow transplant patient after platelet transfusion

BACKGROUND: Many reports document the transmission of human parvovirus B19 (B19) infection by clotting factor concentrates manufactured from large plasma pools. Transmission via other blood components originating from a single donor or a small number of donors, however, seems to occur only rarely. The study reported here identifies a B19 infection that was transmitted via a platelet donation. CASE REPORT: A multiply transfused allogeneic bone marrow transplant patient developed chronic anemia due to persistent B19 infection. The anemia responded to therapy with intravenous immunoglobulin. It was postulated that a transfusion was the source of the B19 infection. Archived sera from 90 implicated blood donors were tested for B19 IgM and DNA by the use of dot-blot hybridization and a nested polymerase chain reaction with primers from the B19 nonstructural gene. B19 DNA from patient and donor sera were sequenced. One of the 90 blood donors (Donor A) was B19 IgM positive and had a high level of B19 DNA. The patient was viremic 3 days after transfusion of platelets from this donor, and the sequence of B19 DNA from the patient exactly matched that of B19 DNA from the donor. A second blood donor (Donor B) had a low level of B19 DNA but was IgM negative. The patient showed no evidence of B19 infection after the transfusion of red cells from Donor B, and the sequence of this donor's B19 DNA was different from that in the patient. CONCLUSION: Blood Donor A with asymptomatic acute B19 infection was the source of B19 infection in the bone marrow transplant patient. Donor B with a low level of B19 DNA was not the source of infection.