Cytodiagnosis of parvovirus B19 infection from ascites fluid of hydrops fetalis: report of a case.

The cytologic changes in the smears of fetus ascites fluid with parvovirus B19 infections are described. Cytology revealed the ground-glass appearance of the nuclei having a perinuclear halo, and the nuclear chromatin was spread as a thin rim around the inclusion. Subsequently, monoclonal antibodies for parvovirus B19 were applied to identify the specific antigen in the Papanicolaou-destained specimens. Positive staining reaction products were found throughout the cytoplasm of cells. Similar phenomena were confirmed in paraffin-embedded tissue sections of many organs in autopsy materials. It is hoped that recognition of those virus-infected cells in the body cavity fluid of the fetus will be helpful in making a diagnosis of hydrops fetalis associated with parvovirus B19 infections of the pregnant woman.