Routine prenatal ultrasound evaluation may reveal traits such as abnormal presentation close to due date, rhizomelia, diaphragmatic abnormalities such as hernias, anal defects, and heart malformations, especially ventricular septal defect, all of which are highly suggestive of this syndrome.

After birth, the first sign that draws the clinician's attention is hypotonia, that may be severe enough to interfere with respiration and deglutition. Newborns and children also have a specific phenotype, characterized by facial dimorphism: "coarse" facies, high forehead, sparse lashes and eyebrows, shallow supraorbital ridges, hypertelorism, flat nasal bridge, long philtrum [1], short neck, low-implanted ears, large tongue, hypoplastic nails and small hands, sparse hair and areas of unusual skin pigmentation [2]. The hypotonia persists as the child grows older, leading to difficulties in sitting, standing, and mobility. The clinical picture is completed by intellectual disability, manifested as severe or profound mental deficiency, deafness, seizures, hypoplastic lungs and speaking difficulties. Other abnormalities such as cleft palate, supernumerary nipples, genital malformations, auditory canal stenosis, extra fingers or toes or bald scalp areas may also occur. The neurologic prognosis of these patients is grim, with severely disabled motor capabilities and incontinence [3] [4].

Diaphragmatic hernias are considered to be highly specific and are frequent [5].

These traits may not be present in all affected individuals or may be less prominent. The severity of genotype abnormalities does not correlate with the clinical features of the newborn [6]. In other cases, different sides of the body may be affected unevenly.

• Coarse Facial Features

  The clinical symptoms associated with this condition were first recognized in 1977, when Pallister described two adults, aged 19 and 37, who had profound retardation, severe hypotonia, coarse facial features, and pigmentary abnormalities. [obgyn.mhmedical.com]

  Systemic features in childhood are numerous and variable, and include most frequently "coarse" facial features, midface malformations, psychomotor delay, hypotonia, scalp hair sparsity, and variegated lightly and darkly pigmented skin.1-9 We describe [jamanetwork.com]

  facial features Coarse facial appearance 0000280 Frontal bossing 0002007 Hypertelorism Wide-set eyes Widely spaced eyes [ more ] 0000316 Prominent forehead Pronounced forehead Protruding forehead [ more ] 0011220 Short nose Decreased length of nose Shortened [rarediseases.info.nih.gov]

  facial features as child gets older, broad nasal bridge, streaks or patches of lighter or darker skin, sparse hair or bald patches, high arched or cleft palate, shorter arms and legs, disproportionate to the body and extra nipples. [dailymail.co.uk]

• Short Finger

  The dysmorphic features included a board forehead with high anterior hairline, hypertelorism, flat nasal bridge, short upturned nose, down turned corners of the mouth, short fingers, single transverse crease in the right hand, and hypotonia. [ashg.org]

  […] bulging out Prominent eyes Prominent globes Protruding eyes [ more ] 0000520 Pulmonary hypoplasia Small lung Underdeveloped lung [ more ] 0002089 Renal cyst Kidney cyst 0000107 Renal dysplasia 0000110 Seizures Seizure 0001250 Short phalanx of finger Short [rarediseases.info.nih.gov]

• Pediatric Disease

  Keywords : ANESTHESIA [Pediatric]; DISEASES [Pallister-Killian syndrome]. [scielo.br]

• Single Transverse Palmar Crease

  transverse palmar crease 0000954 Small scrotum Underdeveloped scrotum 0030276 Somatic mosaicism 0001442 Sparse anterior scalp hair Sparse scalp hair at front of head Thin scalp hair at front of head [ more ] 0004768 Sparse eyelashes Scant eyelashes Scanty [rarediseases.info.nih.gov]

• Failure to Thrive

  Her growth curve is below the third centile, indicating failure to thrive. She has global delay in development and is presently attending the Early Intervention Program for Infants and Children at a special school. [nature.com]

• Macroglossia

  The disorder in older children and young adults is characterized by a coarse and flat facies, macroglossia prognathia, everted lower lip, and severe psychomotor retardation with muscular hypertonia and contractures. [ncbi.nlm.nih.gov]

  Macroglossia and pointed chin occur with age. Hypotonia is present at birth with contractures developing with age. A wide range of congenital malformations may be present, the most specific being diaphragmatic and anal defects. [orpha.net]

  CASE REPORT: A 5-year-old male patient with typical PKS characteristics (facial dimorphism, temporal alopecia, micrognathia, macroglossia, mental retardation, seizures and pigmentary skin lesions) was scheduled to magnetic resonance of the head under [scielo.br]

  As patients pass into adolescence, the syndrome is characterized by a coarse and flat face, macroglossia, prognathism, inverted lower lip and psychomotor retardation with muscular hypertonia and contractures. [popflock.com]

• High Arched Palate

  Oro-dental features, such as "Pallister lip," macroglossia, delayed eruption of primary teeth, high arched-palate, prognathism, and cleft palate have been occasionally reported in the medical literature. [ncbi.nlm.nih.gov]

  PKS has the following characteristics: low muscle tone facial features that are common to the syndrome-high forehead, broad nasal bridge, wide space between the eyes sparse scalp hair at birth high, arched palate hypopigmentation extra nipples cognitive [pkskids.net]

  arched palate or cleft palate hypopigmentation cognitive and developmental delays diaphragmatic hernias(about 40%;this potentially serious birth defect allows the stomach and intestines to move into the chest, where they can crowd the developing heart [physio-pedia.com]

  The facial appearance includes coarse facies (coarseness becomes more pronounced with age), prominent forehead, hypertelorism, upslanting palpebral fissures with epicanthal folds, small nose with upturned nares, high arched palate, macrostomia, long philtrum [molecularcytogenetics.biomedcentral.com]

• Macrostomia

  The syndrome presents with a recognizable pattern of findings including: pigmentary skin changes, characteristic facial features (sparse anterior scalp hair, flattened midface, macrostomia, and coarsening of the facial features), and developmental delay [ncbi.nlm.nih.gov]

  The facial appearance includes coarse facies (coarseness becomes more pronounced with age), prominent forehead, hypertelorism, upslanting palpebral fissures with epicanthal folds, small nose with upturned nares, high arched palate, macrostomia, long philtrum [molecularcytogenetics.biomedcentral.com]

• Dry Skin

  The girl has woolly and sparse hair, absence of lateral eyebrows, dry skin, brittle nails, hypopigmented patches, frontal bossing, hearing loss, hypertrophic dilated cardiomyopathy, polydactyly, and mild developmental delay. [ncbi.nlm.nih.gov]

• Hearing Impairment

  Vision and hearing impairments may occur. Patients may also exhibit congenital heart defects, gastroesophageal reflux, cataracts and supernumerary nipples. Diaphragm problems are also possible. [popflock.com]

  Vision and hearing impairments may occur. Patients may also exhibit congenital heart defects, gastroesophageal reflux, cataracts, and supernumerary nipples. Diaphragm problems seen in newborns can lead to death shortly after birth. [wikidoc.org]

  impairment Deafness Hearing defect [ more ] 0000365 Hyperpigmented streaks 0007572 Hypertonia 0001276 Hypertrophic cardiomyopathy Enlarged and thickened heart muscle 0001639 Hyperventilation Rapid breathing 0002883 Hypopigmented streaks 0007535 Hypoplastic [rarediseases.info.nih.gov]

  impairment Underdeveloped or improperly developed genitals Gastrointestinal defects, abnormal kidney function Reduced growth of head size and body length Severe mental retardation Severe heart defects Hip dislocation at birth, abnormally curved spine [dovemed.com]

• Hypertelorism

  We showed that the most consistent pre-natal ultrasound findings include hypertelorism, broad neck, shorts limbs, abnormal hands or feet, diaphragmatic hernia and hydramnios. [ncbi.nlm.nih.gov]

  Seizures and developmental delay Callosum disgenesy, shortage white matter, rarefied myelinization, kyphosis 3 Male 36y /43y Hypertelorism, flat, broad nasal root, anteverted nostrils, thin upper lip, high-arched palate Normal Inguinal and umbilical [molecularcytogenetics.biomedcentral.com]

  Craniofacial manifestations include a coarse'' face with flat profile, high forehead with temporo-frontal balding, sparseness of eyebrows and lashes, shallow supraorbital ridges, upslanting palpebral fissures, hypertelorism, flat and broad nasal bridge [orpha.net]

• Broad Nasal Bridge

  Craniofacial manifestations include a coarse'' face with flat profile, high forehead with temporo-frontal balding, sparseness of eyebrows and lashes, shallow supraorbital ridges, upslanting palpebral fissures, hypertelorism, flat and broad nasal bridge [orpha.net]

  PKS has the following characteristics: low muscle tone facial features that are common to the syndrome-high forehead, broad nasal bridge, wide space between the eyes sparse scalp hair at birth high, arched palate hypopigmentation extra nipples cognitive [pkskids.net]

  Subsequent interphasic FISH with a centromeric probe detected tetrasomy 12p in mosaic.The postnatal phenotype of PKS is quite severe and include coarse facies with a high forehead, sparce scalp hair, hypertelorism, broad nasal bridge, hypotonia, streaks [fupress.net]

  Major symptoms may include a coarse face with a high forehead, sparse hair on the scalp, an abnormally wide space between the eyes, a fold of the skin over the inner corner of the eyes, and a broad nasal bridge with a highly arched palate. [rarediseases.org]

• Short Neck

  Here, we report on an unusual case of i(12p) in a 15-year-old boy presenting with mild mental retardation, minor facial features (long face, prognathism, short neck), normal weight, length, and OFC parameters as well as hyperpigmented streaks. [ncbi.nlm.nih.gov]

  neck [ 8, 9 ]. [synapse.koreamed.org]

  neck A number of other clinical features can help identify PKS. [forgottendiseases.org]

  neck Decreased length of neck 0000470 Short stature Decreased body height Small stature [ more ] 0004322 Sparse and thin eyebrow Thin, sparse eyebrows 0000535 Sparse hair 0008070 Thick upper lip vermilion Full upper lip Increased volume of upper lip [rarediseases.info.nih.gov]

  neck (OMIM #601803; ). [dx.doi.org]

The diagnosis relies on the detection of the mosaic tetrasomy of isochromosome 12p. This can be done by various techniques, performed on different cell types. The most reliable choice is to perform an amniocentesis, as i(12p) is found in all amniocytes in fetuses suffering from this condition [7]. Similarly, all newborn bone marrow cells have this trait [8], whereas a variable percentage of fibroblasts, lung, liver, testes and spleen cells exhibit the abnormality, hence the "tissue-specific mosaicism" term. Lymphocytes are infrequently affected, therefore blood karyotype may not be a reliable method to diagnose this illness, especially due to the high turnover of blood cells. Fibroblasts may be obtained from buccal smears or skin areas with different pigmentation. The percentage of i(12p) cells does not correlate with disease severity [9]. Furthermore, the number of detectable diseased cells decreases as the patient ages [10].

Fluorescence in situ hybridization (FISH) [11] [12] and interphase FISH are reliable diagnostic methods [13]. Other methods include karyotype analysis, array comparative genomic hybridization (CGH) and chromosomal microarray. A normal karyotype of blood cells does not exclude the diagnose. In case clinical doubt persists, newer diagnostic methods, such as spectral karyotyping and multiplex-FISH may shed light over the case [14].

• 3 Hz Spikes

  Renzo Guerrini, Michelle Bureau, Marie‐Geneviève Mattei, Agatino Battaglia, Marie‐Claude Galland and Joseph Roger, Trisomy 12p Syndrome: A Chromosomal Disorder Associated with Generalized 3‐Hz Spike and Wave Discharges, Epilepsia, 31, 5, (557-566), (2007 [doi.org]

The material is in no way intended to replace professional medical care by a qualified specialist and should not be used as a basis for diagnosis or treatment. [orpha.net]

Combination treatment with high-dose pyridoxal phosphate and sodium valproate eliminated seizures and improved the electroencephalographic abnormalities. [ncbi.nlm.nih.gov]

Due to intellectual disability, it was decided to make the dental treatments under moderate sedation. [hindawi.com]

Treatment and management of Pallister-Killian Mosaic Syndrome is based on the severity of the condition and signs and symptoms presented. [dovemed.com]

Prognosis Prognosis is usually poor. Death may occur perinatally, mainly due to diaphragmatic hernias, or during the first years of life in about a half of patients. [orpha.net]

Despite a variable prognosis in terms of response to therapy, a significant proportion of patients achieved good seizure control. Copyright 2012 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved. [ncbi.nlm.nih.gov]

It is generally observed that the child’s mobility is affected, in most cases The prognosis depends on the severity of the signs and symptoms. [dovemed.com]

[…] be an error in the skin cells that is not present in other tissues that came from other germ layers Surveillance, management, and treatment options [ edit ] There is no specific therapy for individuals with Pallister-Killian Syndrome Because of poor prognosis [en.wikibooks.org]

Extra ring chromosomes might be a more common etiology for PKS than previously thought, given the difficulty in their characterization before the advent of aCGH. [ncbi.nlm.nih.gov]

Etiology Patients with PKS have mosaïcism for a supernumerary isochromosome 12p, resulting in four copies of the short arm of chromosome 12 instead of the normal two. The isochromosome is mostly of maternal origin. [orpha.net]

The genetic etiology is a result of isochromosomes that have either two q arms (long) or two p arms (short). Therefore isochromosome 12p is a chromosome 12 with two p arms. Most cells have two copies of each chromosome with one from each parent. [slideshare.net]

Etiology : Mosaic tissue-limited tetrasomy for chromosome 12p. (Presence of an extra isochromosome 12p. So in effect there are 4 copies of 12p.) Usually picked up only on a buccal smear or skin biopsy sample. Inheritance : Sporadic condition. [genetics4medics.com]

Summary Epidemiology Incidence is uncertain and is estimated around 1/25,000. Clinical description A number of cases are prenatally diagnosed because of abnormal ultrasonic findings, and abnormal presentation at birth is usual. [orpha.net]

In addition, we review the several cases in which hiccups have been associated with seizures and how this may relate to the neural pathways involved in the pathophysiology of hiccups. [worldwidescience.org]

This study suggests that individuals affected by PKS should be observed closely for oro-dental diseases and a multidisciplinary approach is needed to implement the right preventive measures. 2016 Wiley Periodicals, Inc. [ncbi.nlm.nih.gov]

Abdul-Rahman 1 1) Dept Preventive Medicine; 2) Dept Pediatrics, Univ of Mississippi Med Ctr, Jackson, MS. Pallister-Killian Syndrome (PKS) was first reported in 1977 with mosaicism in fibroblasts for an extra chromosome composed of 12p. [ashg.org]

Medical researchers are still trying to understand the unique Pallister-Killian Syndrome and find ways to prevent its occurrence Even though PKS is not an inherited syndrome, those with a family history of tetrasomy (disorder with extra pairs of chromosomes [dovemed.com]

April 18, 2019 Measles Surge and Importance of Prevention, Protection Given the recent measles outbreak in Minnesota, Gillette is sharing helpful information for parents courtesy of the Minnesota Department of Health. [gillettechildrens.org]

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