A CLINICAL AND EPIDEMIOLOGIC-STUDY OF HUMAN PARVOVIRUS B19 INFECTION IN FETAL HYDROPS USING PCR SOUTHERN BLOT HYBRIDIZATION AND CHEMILUMINESCENCE DETECTION

Ninety-eight samples from 80 cases of spontaneous abortions after feta l death or hydrops fetalis from 12,000 pregnant women were examined us ing PCR. DNA was extracted from amniotic fluid, fetal blood, ascitic f luid and fetal biopsies or placenta specimens using QIA amp kits (QIAG EN). A 270-bp length fragment located within the B19 gene NS1 was ampl ified using PCR followed by electrophoresis and southern-blot hybridiz ation assay using a horseradish peroxidase-labelled probe and chemilum inescence detection. This assay was able to detect 1 to 10 DNA copies in a 10 mu l sample. Parvovirus B19 was identified in 11 cases (14% of fetal hydrops; 1 case for 1,100 pregnancies). Amniotic fluid was the most common and reliable sample to assess the diagnosis. Gestational a ge ranged from 17 to 28 weeks (mean 23 weeks). IgM antibodies were det ected in 3 maternal sera, 2 patients of which reported an exposure to B19 infection during pregnancy. In 2 cases, intrauterine blood transfu sions led to the cessation of symptoms and to birth of normal babies. (C) 1998 Wiley-Liss, Inc.