Individuals with PKS present prenatally or at birth with multiple birth defects. These defects include: brain atrophy, agenesis of the corpus callosum, polymicrogyria of the brain, and/or spot calcifications in the brain's lateral sulcus; deafness and/or blindness; autonomic nervous system dysfunctions such as anhidrosis, hypohidrosis, and/or episodic spells of hyperventilation interspersed with breath-holding; symptoms of spinal cord malformations; profound or less commonly mild to severe intellectual disability; epileptic seizures; heart and/or anal defects; diaphragmatic hernias; marked muscle weakness; supernumerary nipples; abnormal facial features such as frontal bossing, high frontal hairline, balding around the temple and frontal areas, sparse eyebrows and lashes, hypertelorism, small and flat nose, full cheeks, long philtrum, large mouth with downturned corners, thin cupid's bow-shaped upper lip, micrognathia (i.e. undersized jaw), disformed ears that are low-set, thick eyebrows, and/or prominent lips and chin; abnormal oral/dental features such as enlarged tongue, overgrowth of the alveolar ridge and/or gums, delayed teeth eruption, and/or missing or double teeth; patchy skin depigmentations; skeletal anomalies such as limb shortening, lymphedema, increased soft tissues in the extremities, short/broad palms and/or fingers, and/or clinodactyly of the fifth fingers or toes; excessive prenatal and birth weights followed by postnatal declines in growth rates; delayed closure of the anterior fontanel; and/or delayed puberty in males but not females.
Pallister–Killian syndrome
Hapnes Boman Skeie syndrome
Scheie syndrome
Catel–Manzke syndrome
Gerstmann–Sträussler–Scheinker syndrome
Ohtahara syndrome
Cohen syndrome
Cohen-Gibson syndrome