GIGANTISM – Causes and Risk Factors, Clinical Manifestations, Diagnostic Evaluations and Management

Gigantism is abnormally large growth due to an excess of growth hormone during child-hood, before the bone growth plates have closed. Gigantism begins before epiphyseal closure and causes proportional overgrowth of all body tissues.

CAUSES AND RISK FACTORS

The most common cause of too much growth hormone release is a noncancerous (benign) tumor of the pituitary gland. Other causes include: Carney complex, McCune-Albright syndrome (MAS), Multiple endocrine neoplasia type 1 (MEN -1) and Neurofibromatosis. Gigantism is very rare.

 

CLINICAL MANIFESTATIONS

The child will grow in height, as well as in the muscles and organs. This excessive growth makes the child extremely large for his or her age. Other symptoms include:

  • Delayed puberty
  • Double vision or difficulty with side (peripheral) vision
  • Frontal bossing and a prominent jaw
  • Headache
  • Increased sweating
  • Irregular period (menstruation)
  • Large hands and feet with thick fingers and toes
  • Release of breast milk
  • Thickening of the facial features
  • Weakness​


DIAGNOSTIC EVALUATIONS

CT or MRI scans of the head showing pituitary tumor. Failure to suppress serum growth hormone (GH) levels after an oral glucose challenge (maximum 75g), high prolactin levels and increased insulin growth factor-I (IGF-I) levels.

Damage to the pituitary may lead to low levels of other hormones, including: Cortisol, Estradiol (girls), Testosterone (boys) and Thyroid hormone

MANAGEMENT

In pituitary tumors with well-defined borders, surgery is the treatment of choice and can cure many cases. Treatment is mainly surgical (transfenoidal adenectomy or hypophysectomy of the acidophil adenoma is the treatment of choice.

For situations in which surgery cannot completely remove the tumor, medication is the treatment of choice. The most effective medications are somatostatin analogs (such as octreotide or long-acting lanreotide), which reduce growth hormone release. Dopamine agonists (bromocriptine mesylate, cabergoline) have also been used to reduce growth hormone release, but these are generally less effective. Pegvisomant, a medication that blocks the effect of growth hormone, may be used.

Radiation therapy has also been used to bring growth hormone levels to normal. However, it can take 5-10 years for the full effects to be seen and almost always leads to low levels of other pituitary hormones. Radiation has also been linked to learning disabilities, obesity and emotional changes in children. Most experts will use radiation only if surgery and medication fail.

GIGANTISM – Causes and Risk Factors, Clinical Manifestations, Diagnostic Evaluations and Management
nursinfo nursing notes for bsc, p.c. or pb. bsc , msc and gnm nursing

GIGANTISM – Causes and Risk Factors, Clinical Manifestations, Diagnostic Evaluations and Management