Prenatal diagnosis of Pallister-Killian syndrome

Abstract

Pallister-Killian syndrome is a rare and sporadic disorder characterized by the
presence of an extra 12p isochromosome in some body tissues. Its prenatal diagnosis
is complex due to the absence of distinctive or pathognomonic ultrasonographic
features, making it difficult to identify some malformations during the prenatal
period. Among the most common prenatal findings are congenital diaphragmatic
hernia, polyhydramnios, and rhizomelic limb shortening. Genetic diagnosis is
also made difficult by the tissue mosaicism associated with this syndrome and
the diminution of the abnormal isochromosome-bearing clone. Amniocentesis is
considered the most appropriate procedure for genetic diagnosis since most of
the cells in the amniotic fluid are epithelial cells shed from the fetal skin. A case of
prenatal diagnosis of Pallister-Killian syndrome is presented.