PALLISTER-KILLIAN-SYNDROME [I(12P)] - FIRST PRENATAL-DIAGNOSIS USING CORDOCENTESIS IN THE 2ND-TRIMESTER CONFIRMED BY IN-SITU HYBRIDIZATION

Pallister-Killian syndrome (PKS) is the most frequent form of partial autosomal tetrasomy 12p in humans. Sufferers have a mosaic of isochrom osome 12p [i(12p)]. We report the first pre-natal diagnosis on fetal b lood cells after cordocentesis during the second trimester. The extra chromosome was first diagnosed by in situ hybridization. Fluorescence in situ hybridization (FISH) was used to count the interphase and/or m etaphase cells containing the isochromosome. A review of the literatur e identified 27 other reports of PKS diagnosed pre-natally. We showed that the most consistent pre-natal ultrasound findings include hyperte lorism, broad neck, shorts limbs, abnormal bands or feet, diaphragmati c hernia and hydramnios. Recognition of this congenital malformation p attern pre-natally may allow utilization of FISH.