The etiology of gigantism is not well understood. Some patients have underlying genetic mutations leading to excess growth-hormone production, while others can have growth-hormone secreting tumors (although this is less common in children). Gigantism can be an isolated finding or present as part of a syndromic phenotype, such as McCune-Albright syndrome or multiple endocrine neoplasia (MEN) type 1 and MEN type 4. It is more common in males.
Patients present with accelerated linear growth and macrocephaly with a lag in weight gain. There is no uniform phenotype for patients with gigantism, but coarse facial features and large hands and feet have been described in several patients.
E22.0 – Acromegaly and pituitary gigantism
80849007 – Gigantism
Differential Diagnosis & Pitfalls
- Genetic tall stature
- Acromegaly – occurs in adults and is characterized by hyperpituitarism after ossification is complete
- Precocious puberty (see central precocious puberty)
- Klinefelter syndrome
- Sotos syndrome
- Weaver syndrome
- Marshall-Smith syndrome
- Beckwith-Wiedemann syndrome