DISCORDANT DIRECT AND CULTURE RESULTS FOLLOWING CHORIONIC VILLUS SAMPLING AND THE DIAGNOSIS OF A 3RD CELL-LINE IN THE FETUS

We report a case of discordant non-mosaic karyotypes following chorion ic villus sampling (CVS). A 45,XX,der(21;21)(q10;q10) karyotype was fo und on direct preparation of cytotrophoblasts and 46,XX was found on l ong-term culture of mesenchymal core cells. Analysis of amniotic fluid cells and fetal tissue revealed a third karyotype: 46,XX,+21,der(21;2 1)(q10;q10). Had only culture analysis been performed, follow-up studi es might not have been undertaken. This case demonstrates the importan ce of direct CVS preparation in helping to identify fetal abnormalitie s, and the need for follow-up of discordant CVS results. (C) 1997 by J ohn Wiley & Sons, Ltd.