A Case of Pallister-Killian Syndrome in a Newborn

Pallister-Killian syndrome (PKS) is a rare disorder caused by tissue-limited mosaicism tetrasomy of chromosome 12p. Affected newborns show a typical dysmorphic pattern: macrosomia, coarse facies, hypertelorism, small nose with long philtrum, V-shaped upper lip, low set ears, frontotemporal alopecia, and patchy pigmentary skin and hair anomalies. Seizures and developmental delay, cardiac defects, diaphragmatic hernia, and renal/anal malformations may be associated.

Here, we report the case of a newborn with multiple congenital malformations, later diagnosed with PKS.

Phenotypic and cytogenetic variability of PKS, together with the lack of correlation between tetrasomic cells' proportion and disease severity, may be challenging for diagnosis. Therefore, a detailed physical examination is mandatory for early clinical suspicion and to guide further investigations. The usefulness of array-CGH performed on peripheral blood should also be emphasized as a sensitive diagnostic tool.