An Acephalus Acardius Amorphous Fetus in a Monochorionic Pregnancy With Sex Discrepancy

Wanda Lattanzi, Rosa P. De Vincenzo, Fabio De Giorgio, Egidio Stigliano, Arnaldo Capelli, Vincenzo Arena
2006 Twin Research and Human Genetics  
AbstractAcephalus acardiais among the most severe malformations described in fetuses, with an incidence of about 1 in 35,000 births and is due to twin-to-twin transfusion syndrome, frequently occurring in monochorionic twin pregnancies. The severity of the syndrome depends upon the type of the anastomoses arising between the vascular networks of the two fetuses, usually configuring the 'twin reverse arterial perfusion syndrome'. No clear and univocal etiological explanation is known, though few
more » ... cases with chromosomal abnormalities have been reported so far. In some cases the fusion of two or more separate placentae of dizygotic fetuses occurs, leading to monochorionic twinning. Few cases of acardius amorphous with complete autoptical examination have been described so far. We report a case of acephalus acardius amorphus fetus, showing features of extremely severe sistemic immaturity with very few structured organs. Defined external and autoptic examinations have been performed on the dismorphic twin, along with the histological examination of tissue samples. Kariotype analysis showed sex discrepancy between the twins, as a normal female kariotype had been detected in the acephalus acardius while the living co-twin was a normal healthy male. The analysis of the placenta showed the vascular anomalies leading to the twin-to-twin transfusion syndrome.
doi:10.1375/twin.9.5.697 pmid:17032553 fatcat:dku6shxjgfailhzdaada7smxhq