Severe anemia due to B19 parvovirus infection in children with acute leukemia in remission.

Two children developed severe anemia with reticulocytopenia while on maintenance chemotherapy for acute lymphoblastic leukemia. Bone marrow examination revealed marked erythroid hypoplasia and giant megaloblasts without evidence of relapse. One patient had evidence of B19 Parvoviremia at the time of severe anemia but failed to produce anti B19 antibodies. Despite the failure to mount an antibody response, the patient had no recurrence of viremia or anemia during the two years of follow-up after the infection. The other patient had no evidence of viremia or elevated anti-B19 antibodies at the time of anemia. However, when his serum was tested 16 months after the episode of anemia, he had elevated IgG and IgM antibodies against B19 parvovirus. The patient did not experience recurrent viremia or anemia over a two year period. Thus, patients with leukemia are at risk to develop severe anemia when infected with B19 parvovirus.