Measurement of the levels of growth hormone (GH) and its related factor insulin-like growth factor I (IGF-I) is essential for the diagnosis and treatment of GH deficiency (GHD) and conditions related to excess GH such as acromegaly and pituitary gigantism.
Increased secretion of growth hormone leads to gigantism in children and acromegaly in adults; the genetic causes of gigantism and acromegaly are poorly understood.