Sotos syndrome (formerly cerebral gigantism)

Page most recently updated 7 September 2026

This page focuses on the reported psychiatric associations, which may be the initial presenting manifestation, and on other clinical features that may assist the psychiatrist or primary care physician in identifying the underlying diagnosis, considered through the lenses of the diagnostic lenses framework.

Sotos syndrome (formerly cerebral gigantism) is a rare genetic disorder. It is generally inherited in an autosomal dominant manner, with most cases resulting from a de novo pathogenic variant, although inherited cases occur. The phenotype may resemble Malan syndrome and Weaver syndrome, particularly in its overgrowth, macrocephaly, and distinctive facial features, but these conditions are genetically distinct. Sotos syndrome is generally associated with milder intellectual impairment and less prominent ophthalmologic abnormalities than Malan syndrome, while advanced bone age and camptodactyly are particularly useful distinguishing features of Weaver syndrome. A distinctive presentation of Sotos syndrome may include the combination of generalized overgrowth with large body size, macrocephaly, large hands and feet, and poor coordination.

It can present with psychiatric features such as autism spectrum disorder (ASD), anxiety, specific phobias, hyperactivity, aggression, behavioral dysregulation, and sleep disturbance. Difficulties with social interaction and recognizing social cues may also occur. ADHD appears to be less common than in some other neurodevelopmental syndromes, although neuropsychiatric assessment for ADHD remains appropriate. Cognitive impairment, developmental delay, and speech and language impairment are common, with intellectual impairment ranging from mild to severe.

From a morphologic lens perspective, other features include (but are not limited to):

  • Macrocephaly

  • Coarse face

  • Midface retrusion

  • Prognathism

  • Widely spaced eyes

  • Downslanted palpebral fissures

Other characteristic features include advanced bone age, hypotonia, joint hypermobility, and skeletal abnormalities, including scoliosis and pes planus. Cardiovascular manifestations may include patent ductus arteriosus, septal defects, and other congenital heart abnormalities. Neurologic manifestations may include seizures/epilepsy and structural brain abnormalities, most commonly ventriculomegaly. Additional reported features include renal abnormalities, particularly vesicoureteral reflux, hearing impairment, ophthalmologic abnormalities including strabismus and refractive errors, constipation, gastroesophageal reflux, feeding difficulties, genitourinary abnormalities, dental abnormalities, and neonatal complications. An increased risk of malignant tumors has been reported, including sacrococcygeal teratoma and neuroblastoma, although the absolute risk is low and routine cancer screening is not recommended.

Early diagnosis is important to identify and monitor potentially significant developmental, behavioral, neurologic, cardiac, renal, musculoskeletal, auditory, ophthalmologic, gastrointestinal, and oncologic complications, recognize neuropsychiatric needs early, and institute tailored multidisciplinary surveillance and treatment.

Selected references and further reading — Morphologic lens

Jones KL, Jones MC, del Campo M. Smith's recognizable patterns of human malformation. 8th ed. Philadelphia: Elsevier; 2021.

Reardon W. The bedside dysmorphologist: a guide to identifying and assessing congenital malformations. 2nd ed. Oxford: Oxford University Press; 2016.

Allanson JE, Biesecker LG, Carey JC, Hennekam RCM. Elements of morphology: introduction. Am J Med Genet A. 2009;149A(1):2-5. doi:10.1002/ajmg.a.32601.

Hennekam RCM, Biesecker LG, Allanson JE, Hall JG, Opitz JM, Temple IK, Carey JC; Elements of Morphology Consortium. Elements of morphology: general terms for congenital anomalies. Am J Med Genet A. 2013;161A(11):2726-2733. doi:10.1002/ajmg.a.36249.