Parvovirus B19 infection in Taiwanese patients with hematological disorders

Human parvovirus B19 has a strong tissue tropism for erythroid progenitor cells and is a causative agent for anemia. However, it remains unclear whether patients with hematological disorders are at a higher risk of B19 infection. In the present study, we evaluated the prevalence of B19 infection in 278 patients with hematological disorders by indirect antibody capture enzyme-linked immunosorbent assay. Virus inoculation into cell culture (of TF-6, WRL-68, and HL-60) was carried out using serum from patients with positive IgM anti-B19 and was then examined by nested polymerase chain reaction, dot-blot analysis, and sequence analysis. Our data demonstrated that the total seropositive rates of either IgG or IgM were 71.9%. The seropositive rates increase significantly with age (P < 0.001). After adjustment for age, the seropositive rate was significantly higher in our patients than in the general population with standardized rate ratio of 1.56 (95% CI = 1.43-1.68). No significant difference was found among different disease subgroups (P = 0.311). Nine patients (3.2%) had active B19 infection with positive IgM antibody, with four diagnosed as having idiopathic thrombocytopenic purpura (ITP). Viremia of B19 virus could be detected in eight of nine patients, including three patients in serum only, three patients in bone marrow only, and two patients in both serum and bone marrow. We conclude that patients with hematological disease have higher seropositive rates for B19 than occur in normal controls and that study of occult parvovirus B19 infection is recommended in patients with hematological disease.