According to the Larousse dictionary: 'gigantism' refers to an abnormally large size compared to the average size of individuals of the same age and same gender. More specifically, gigantism means that the individual’s size is greater than two standard deviations from mean values for growth based on age and sex according to growth reference tables.

Several syndromes (see name in database for more details) are characterized by gigantism, such as:

-        Beckwith-Wiedemann: sporadic, deregulation of the expression of genes regulating growth on 1 1p15.5; exaggerated pre - and postnatal growth; macroglossia, omphalocele, visceromegaly; risk of solid tumor

-        Simpson-Golabi-Behmel : X-linked or sporadic; mutation of the GPC3 gene on Xq26; exaggerated pre - and postnatal growth; macroglossia, cleft palate, congenital heart disease

-        Sotos : sporadic; mutation of the 5q35 gene coding for a protein (NSD1) of a nuclear receptor; exaggerated prenatal growth with transient acceleration of postnatal growth; macrocephaly, hypertelorism, mental retardation with hypotonia

-        Weaver syndrome: sporadic; sometimes mutation in the same gene as Sotos syndrome; exaggerated pre- or post-natal growth; macrocephaly, hypertelorism; micrognathia, mental retardation, heart defects.

-        gigantism [MIM 102 200] formerly called Lee pituitary gigantism: excessive production of growth hormone before the fusion of the epiphyses; especially in adolescence; very fast growth, wide hands and  feet; macroglossia, sometimes diabetes mellitus and psychological disorders. Corresponds to acromegaly in adults.

-         inversion of a copy of chromosome 12: 1 case reported, linked to a mutation of the HMGA2 gene on chromosome 12; exaggerated postnatal growth; small cerebellar tumor; visceromegaly.

Anesthetic implications: 

difficult intubation or ventilation with a facial mask; careful selection of the size of the endotracheal tube; ECG and echocardiography.

References : 

• Wong TB, Rowell JC, Waldhausen JHT, Parisi MA, Jonmarker C. 
  Anesthesia in a 12 year old boy with somatic overgrowth secondary to pericentric inversion of chromosome 12. 
  J Clin Anesth 2013; 25: 135-7.

Updated: April 2019