What are the signs and symptoms of Pallister-Killian mosaic syndrome? The Human Phenotype Ontology provides the following list of signs and symptoms for Pallister-Killian mosaic syndrome. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Abnormal hair quantity 90% Aplasia/Hypoplasia of the eyebrow 90% Cognitive impairment 90% Decreased body weight 90% Delayed eruption of teeth 90% Delayed skeletal maturation 90% Downturned corners of mouth 90% Hypohidrosis 90% Joint hypermobility 90% Long philtrum 90% Muscular hypotonia 90% Ptosis 90% Short neck 90% Thin vermilion border 90% Anteverted nares 50% Coarse facial features 50% Frontal bossing 50% Hypertelorism 50% Short nose 50% Telecanthus 50% Upslanted palpebral fissure 50% Abnormality of the soft palate 7.5% Strabismus 7.5% Urogenital fistula 7.5% Anal atresia - Anal stenosis - Anteriorly placed anus - Aortic valve stenosis - Aplasia of the uterus - Atria septal defect - Bifid uvula - Broad foot - Broad palm - Cataract - Cleft palate - Clinodactyly of the 5th finger - Coarctation of aorta - Congenital diaphragmatic hernia - Congenital hip dislocation - Cryptorchidism - Depressed nasal bridge - Epicanthus - Flexion contracture - Full cheeks - Hearing impairment - Hyperpigmented streaks - Hypertonia - Hypertrophic cardiomyopathy - Hypopigmented streaks - Hypoplastic labia majora - Hypospadias - Inguinal hernia - Intellectual disability, profound - Intestinal malrotation - Kyphoscoliosis - Macrocephaly - Macroglossia - Macrotia - Mesomelia - Mesomelic/rhizomelic limb shortening - Obesity - Omphalocele - Patent ductus arteriosus - Postaxial foot polydactyly - Postaxial hand polydactyly - Postnatal microcephaly - Prominent forehead - Proptosis - Pulmonary hypoplasia - Renal cyst - Renal dysplasia - Rhizomelia - Seizures - Short phalanx of finger - Short toe - Single transverse palmar crease - Small scrotum - Somatic mosaicism - Sparse anterior scalp hair - Sparse eyebrow - Sparse eyelashes - Stenosis of the external auditory canal - Stillbirth - Supernumerary nipple - Umbilical hernia - Ventricular septal defect - Webbed neck - Wide nasal bridge - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.