Human parvovirus B19-associated thrombocytopenic purpura

We report two patients who presented with thrombocytopenic purpura (TP) associated with primary human parvovirus B19 (B19) infection. One patient also had transient liver dysfunction. In both cases, B19-DNA was detected in serum and bone marrow by polymerase chain reaction. Six months after the illness in patient 1 and 8 months after the illness in patient 2, B19-DNA disappeared from the serum. Serum immunoglobulin (Ig)G antibody to B19 remained positive in both cases, but B19 IgM antibody became negative 3 months after the onset in case 1 and 4 months after the onset in case 2. The mechanism of TP by B19 infection is unknown.