B19 PARVOVIRUS INDUCED FETAL HYDROPS - RAPID AND SIMPLE DIAGNOSIS BY DETECTION OF B19 ANTIGENS IN AMNIOTIC FLUIDS

In our study we describe the direct detection of parvovirus B19 capsid antigens in amniotic fluid samples for the rapid and simple prenatal diagnosis of B19 induced fetal hydrops. The assay was performed on amn iotic fluid specimens from fetal hydrops dotted on nylon membranes. Th e two capsid antigens, VPI and VP2, which represent four per cent and 96 per cent of the capsid, respectively, were detected using a pool of monoclonal antibodies directed against these two proteins and the com plex was visualized by immunoperoxidase staining. The assay could be p erformed in about four hours and positive results were revealed at the end of the reaction as dark blue spots on the nylon membrane. We anal ysed 26 amniotic fluid samples from 26 selected cases of non-immune hy drops for the presence of B19 antigens. Out of these 26 samples, 13 ha d previously proved positive for B19 DNA, detected by dot blot hybridi zation and/or in situ hybridization and/or nested PCR, and 13 had prov ed negative. The results obtained with our assay were compared with re sults obtained for the presence of B19 DNA and a close agreement was f ound. The method is simple and rapid to perform, does not require cost ly instruments, and all the reagents used in the assay are commerciall y available. The:assay described can thus be useful for a prompt couns elling and management of B19 fetal infection. (C) 1998 John Wiley & So ns, Ltd.