[Transient pure red cell aplasia in an adult with acute parvovirus B19 infection: observation of PVB19 DNA by polymerase chain reaction, viral antibody and erythroid cells in the bone marrow].

A 35-year-old female was referred to our hospital for fever and anemia. Physical examination was unremarkable. Complete blood count revealed microcytic hypochromic anemia and reticulocytopenia. The bone marrow cellularity was normal. Some giant pronormoblasts were seen but other erythroid cells were absent. No stainable iron was seen. Parvovirus B19 (PVB19) DNA was detectable by polymerase chain reaction. Anti-PVB19 IgM-antibody was also positive in the serum on admission. Antibodies against rubella, measles, mumps, EB virus and HBs were negative and HBs antigen was also negative. Thus the diagnosis of iron deficiency anemia complicated with pure red cell aplasia secondary to PVB19 infection was made. The PVB19 DNA was still positive on days 6 and 11, suggesting that PVB19 virus persists as long as 3 weeks after the onset of PVB19 infection. However, the erythroid cells had recovered by day 6 after admission suggesting that the development of IgM antibody successfully protected the erythroid cells from infection by the residual PVB19. Hence, careful observation for PVB19 DNA and the antibody may be necessary if immunodeficient patients developed anemia of unknown etiology.