Growth Hormone Deficiency - Causes

Causes

Growth hormone deficiency in childhood commonly has no identifiable cause (idiopathic), and adult-onset GHD is commonly due to pituitary tumours and their treatment or to cranial irradiation. A more full list of causes includes:

• mutations of specific genes (e.g., GHRHR, GH1)
• congenital diseases such as Prader-Willi syndrome, Turner syndrome, or short stature homeobox gene (SHOX) deficiency
• congenital malformations involving the pituitary (e.g., septo-optic dysplasia, posterior pituitary ectopia)
• chronic renal insufficiency
• some infants who are small for gestational age
• intracranial tumors in or near the sella turcica, especially craniopharyngioma
• damage to the pituitary from radiation therapy to the head (e.g. for leukemia or brain tumors), from surgery, from trauma, or from intracranial disease (e.g. hydrocephalus)
• autoimmune inflammation (hypophysitis)
• ischemic or hemorrhagic infarction from low blood pressure (Sheehan syndrome) or hemorrhage pituitary apoplexy

There are a variety of rare diseases which resemble GH deficiency, including the childhood growth failure, facial appearance, delayed bone age, and low IGF levels. However, GH testing elicits normal or high levels of GH in the blood, demonstrating that the problem is not due to a deficiency of GH but rather to a reduced sensitivity to its action. Insensitivity to GH is traditionally termed Laron dwarfism, but over the last 15 years many different types of GH resistance have been identified, primarily involving mutations of the GH binding protein or receptors.