Sotos syndrome is an overgrowth condition that is defined by excessive growth, distinct facial features, and difficulties in learning. Other manifestations such as cardiac and genitourinary anomalies may also be present. This disorder is diagnosed by a physical exam, genetic testing, and possibly imaging.
Sotos syndrome describes a childhood overgrowth disorder that is remarkable for excessive growth, distinguished facial features, and learning disabilities  . Additionally, neonates may present with feeding difficulties, hypotonia, hypoglycemia, and jaundice . Most cases result from NSD1 mutations, of which the majority are sporadic while some are noted to be of autosomal dominant inheritance  . Beckwith-Wiedeman syndrome and Fragile X syndrome are among the differential diagnoses .
Neonates with this overgrowth condition are above average in terms of their weight, length, and occipitofrontal circumference (OFC) . There is a significant growth in the child's first 12 months, which eventually becomes stable . At pubertal age, the growth is appropriate and eventually results in an adult height that falls in the upper range of the normal curve . The OFC remains between 98th and 99.6th percentile throughout the affected individual's life . Moreover, advanced bone age is observed in most patients .
Craniofacial dysmorphia in infancy is striking for a prominent forehead. In childhood, the facies are characterized by an elongated head, macrodolichocephaly, frontal bossing, hypertelorism, downward slanting palpebral fissures, pointed jaw, and a highly arched palate  . These features are less apparent in adulthood although they still have a prominent jaw.
Individuals with Sotos syndrome also exhibit a developmental delay in motor and speech skills and experience a lag in milestones . Additionally, they may demonstrate behavioral problems such as attention deficit hyperactivity disorder (ADHD) and others .
Other manifestations that may be observed in these patients include anomalies of the heart (septal defects) and genitourinary system   . Furthermore, affected children may also manifest with brisk deep tendon reflexes, scoliosis, and seizures   .
Entire Body System
- Advanced Bone Age
Abstract Sotos syndrome (cerebral gigantism) is characterized by macrocephaly, global developmental delay, characteristic facial dysmorphology, and a markedly advanced bone age. [ncbi.nlm.nih.gov]
On bone radiography, most patients will have advanced bone age although this is not a specific test as some patients will have appropriate bone age or delayed growth. [symptoma.com]
- Large Hand
Haploinsufficiency of the NSD1 gene due to 5q35 microdeletions or intragenic mutations is the major cause of Sotos syndrome characterized by generalized overgrowth, large hands and feet with advanced bone age, craniofacial dysmorphic features, learning [ncbi.nlm.nih.gov]
Kids with Sotos syndrome are born with abnormally large heads (macrocrania) and are often taller and heaver throughout the toddler years. They may have a protruding forehead, large hands and feet, and downward-slanting eyes. [kidspot.com.au]
- Large Feet
[…] size Delayed social development Delayed cognitive development Mild mental retardation Speech impairment Down slanting eyes Tallness Large feet Hypertelorism Hypotonia Gum abscesses Unusually large body Delay in developmental milestones Epilepsy Advance [syndromespedia.com]
During follow up, the facies of Sotos syndrome was noted (fig 5 ) and the hands and feet were large with deep creases in the soles of the feet (fig 6 ). [jmg.bmj.com]
- Poor Coordination
coordination, ↑ risk for CA–eg, Wilms' tumor, liver, parotid, ovarian CAs So·tos syn·drome ( sō'tōs sin'drōm ) Cerebral gigantism and generalized large muscles in childhood, with mental retardation and defective coordination; of unknown etiology. [medical-dictionary.thefreedictionary.com]
Performance Abnormalities MOTOR: Poor Coordination (Non progressive, gross>fine) Hyper-reflexia Hypo-tonia (poor sucking may need NGF) Delayed Motor function Variable Mental Deficiency: (IQ 40-129) Mean IQ= 78 Expressive language delay Significant [slideshare.net]
Unusual anxiety and subsequent phobias commonly reported Neurological [ edit ] Hypotonia usually present from birth but improves during childhood Poor coordination and delayed motor skills primarily gross motor (swimming is sport many succeed in) Febrile [en.wikibooks.org]
Most patients have a non progressive neurological dysfunction manifested by clumsiness and poor coordination. [ncbi.nlm.nih.gov]
At neurologic examination, central hypotonia and hyperreflexia were detected. She died at the 17th day of live due to respiratory failure. Patient 4. This patient is the second son of unrelated healthy parents. [nature.com]
Neonates and children presenting with the abovementioned features should undergo a workup that includes a physical exam and the appropriate studies.
Experts recommend that NSD1 gene testing should be the initial test . Confirmatory studies such as fluorescence in situ hybridization (FISH) or multiplex ligation-dependent probe amplification (MLPA) are used for identification of microdeletions . Additionally, DNA sequencing is helpful for the detection of mutations.
Prenatal assessment can be offered to affected parents. Testing can be performed on samples derived from chorionic villus sampling (CVS) or amniocentesis.
Magnetic resonance imaging (MRI) and computed tomography (CT) scanning of the brain may reveal findings such as ventriculomegaly or abnormalities in the trigone and occipital horns   . However, these and other anomalies are not specific .
There is limited information on the development of spinal deformity and the need for treatment in this condition. The medical records and spinal radiographs of 5 consecutive patients were reviewed. [ncbi.nlm.nih.gov]
Treatment of Sotos Syndrome or Cerebral Gigantism As of now, there is no clear cut treatment for this disorder with treatment being only palliative. [epainassist.com]
Prognosis of Sotos Syndrome or Cerebral Gigantism This disorder is in no way a life threatening disorder. The abnormalities that a child experiences fade away as the child grows and the motor function that was lost earlier is gained back with time. [epainassist.com]
"WHAT IS THE PROGNOSIS?" The good news is that Sotos syndrome is not a life-threatening disorder and patients may have a normal life expectancy. [specialeducationalneeds.co.uk]
There aren't biochemical markers for the disease.  Treatment [ edit ] Treatment is symptomatic.  There is no standard course of treatment for Sotos syndrome. [ citation needed ] Prognosis [ edit ] Sotos syndrome is not a life-threatening disorder [en.wikipedia.org]
Prognosis Patients having this kind of diagnosis may have live a life of normal expectancy despite of the fact that it is a non life threatening disorder. [syndromespedia.com]
So·tos syn·drome ( sō'tōs ), [MIM*117550] cerebral gigantism and generalized large muscles in childhood, with mental retardation and defective coordination; of unknown etiology. [medical-dictionary.thefreedictionary.com]
Sotos syndrome is an overgrowth disorder of unknown etiology associated with a high incidence of congenital heart defects. Of 60 patients with Sotos syndrome treated in our hospital, 6 had congenital heart defects. [ncbi.nlm.nih.gov]
Reports from the MHC data base Report from the Questionnaire (PDF) Report from the Observation Chart (PDF) Codes: ICD-10: Q87.3 ORPHA: 821 Estimated occurrence 8:1 000 000 inhabitants Etiology Not completely known. [mun-h-center.se]
Epidemiology [ edit ] Incidence is approximately 1 in 14,000 births.  See also [ edit ] Perlman syndrome Beckwith-Wiedemann syndrome References [ edit ] ^ http://www.exploringautism.org/autism/evaluation.htm ^ "7-foot-tall Broc Brown: Facts". [en.wikipedia.org]
Epidemiology Sotos syndrome is probably one of the most common overgrowth conditions, after the Beckwith-Wiedemann syndrome. The exact birth prevalence remains unknown. Hundreds of cases are reported. [ncbi.nlm.nih.gov]
Epidemiology of pervasive developmental disorders. Pediatric Research, 65 (6), 591–598. CrossRef PubMed Google Scholar Frazier, T. W., Ratliff, K. R., Gruber, C., Zhang, Y., Law, P. A., & Constantino, J. N. (2014). [doi.org]
The pathophysiology is not well known but a common underlying basis between various syndromes (Sotos; Beckwith-Wiedemann; Klippel-Trenaunay) is hypothesised. [moh-it.pure.elsevier.com]
As pathophysiology regarding abnormalities of NSD1 protein remains unknown, further functional studies are necessary. Key concepts Haploinsufficiency of NSD1 causes Sotos syndrome. Sotos syndrome is a genomic disorder. [els.net]
A personalized preventive treatment plan with close supervision of the patient's oral health care is required. [ncbi.nlm.nih.gov]
Ongoing surveillance is key to prevent future complications. How do you Prevent Sotos Syndrome? Sotos syndrome is genetic; hence one cannot prevent it. [medindia.net]
Prevention Rescuing Loved Ones Who Wander Current Issue Issue Archive Online Only En Español Explore Further Healthy Living Discover Brain & Life articles and news about living healthy, safety, prevention, caregiving, and more. [brainandlife.org]
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