Gigantism
Pituitary giant; Overproduction of growth hormone; Growth hormone - excess productionGigantism is abnormal growth due to an excess of growth hormone (GH) during childhood.
Growth hormone
The growth hormone test measures the amount of growth hormone in the blood. The pituitary gland makes growth hormone, which causes a child to grow. ...
Read Article Now Book Mark ArticleCauses
Gigantism is very rare. The most common cause of too much GH release is a noncancerous (benign) tumor of the pituitary gland. Other causes include:
Tumor
A tumor is an abnormal growth of body tissue. Tumors can be cancerous (malignant) or noncancerous (benign).
Read Article Now Book Mark Article- Genetic disease that affects the skin color (pigmentation) and causes benign tumors of the skin, heart, and endocrine (hormone) system (Carney complex)
- Genetic disease that affects the bones and skin pigmentation (McCune-Albright syndrome)
McCune-Albright syndrome
McCune-Albright syndrome is a genetic disease that affects the bones, hormones, and color (pigmentation) of the skin.
Read Article Now Book Mark Article - Genetic disease in which one or more of the endocrine glands are overactive or form a tumor (multiple endocrine neoplasia type 1) or type 4
Multiple endocrine neoplasia type 1
Multiple endocrine neoplasia (MEN) type I is a disease in which one or more of the endocrine glands are overactive or forms a tumor. It is passed do...
Read Article Now Book Mark Article - Genetic disease that forms pituitary tumors
- Disease in which tumors form on the nerves of the brain and spine (neurofibromatosis)
If excess GH occurs after normal bone growth has stopped (end of puberty), the condition is known as acromegaly.
Acromegaly
Acromegaly is a condition in which there is too much growth hormone (GH) in your body.
Read Article Now Book Mark ArticleSymptoms
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
- Very prominent forehead (frontal bossing) and a prominent jaw
Frontal bossing
Frontal bossing is an unusually prominent forehead. It is sometimes associated with a heavier than normal brow ridge.
Read Article Now Book Mark Article - Gaps between the teeth
- Headache
Headache
A headache is pain or discomfort in the head, scalp, or neck. Serious causes of headaches are rare. Most people with headaches can feel much better...
Read Article Now Book Mark Article - Increased sweating
- Irregular periods (menstruation)
- Joint pain
- Large hands and feet with thick fingers and toes
- Release of breast milk
- Sleep problems such as obstructive sleep apnea
- Thickening of the facial features
- Weakness
- Voice changes
Exams and Tests
Your health care provider will perform a physical exam and ask about the child's symptoms.
Laboratory tests that may be ordered include:
- Cortisol
Cortisol
The cortisol blood test measures the level of cortisol in the blood. Cortisol is a steroid (glucocorticoid or corticosteroid) hormone produced by th...
Read Article Now Book Mark Article - Estradiol (girls)
Estradiol
An estradiol test measures the amount of a hormone called estradiol in the blood. Estradiol is one of the main types of estrogens.
Read Article Now Book Mark Article - GH suppression test
GH suppression test
The growth hormone suppression test determines whether growth hormone (GH) production can be suppressed by taking a specific amount of glucose (calle...
Read Article Now Book Mark Article - Prolactin
Prolactin
Prolactin is a hormone released by the pituitary gland. The prolactin test measures the amount of prolactin in the blood.
Read Article Now Book Mark Article - Insulin-like growth factor-I
- Testosterone (boys)
Testosterone
A testosterone test measures the amount of the male hormone, testosterone, in the blood. Both men and women produce this hormone. The test described...
Read Article Now Book Mark Article - Thyroid hormone
Imaging tests, such as CT or MRI scan of the head, also may be ordered to check for a pituitary tumor.
CT
A head computed tomography (CT) scan uses many x-rays to create pictures of the head, including the skull, brain, eye sockets, and sinuses.
Read Article Now Book Mark ArticleMRI
A head MRI (magnetic resonance imaging) is an imaging test that uses powerful magnets and radio waves to create pictures of the brain and surrounding...
Read Article Now Book Mark ArticlePituitary tumor
A pituitary tumor is an abnormal growth in the pituitary gland. The pituitary is a small gland at the base of the brain. It regulates the body's ba...
Read Article Now Book Mark ArticleTreatment
For pituitary tumors, surgery can cure many cases.
When surgery cannot completely remove the tumor, medicines are used to block or reduce GH release or prevent GH from reaching target tissues.
Sometimes radiation treatment is used to decrease the size of the tumor after surgery.
Outlook (Prognosis)
Pituitary surgery is usually successful in limiting GH production.
Early treatment can reverse many of the changes caused by GH excess. Long-term effects on bones, joints, and the heart are common.
Possible Complications
Surgery and radiation treatment may lead to low levels of other pituitary hormones. This can cause any of the following conditions:
- Adrenal insufficiency (adrenal glands do not produce enough of their hormones)
- Diabetes insipidus (extreme thirst and excessive urination; in rare cases)
Diabetes insipidus
Diabetes insipidus (DI) is an uncommon condition in which the kidneys are unable to prevent the excretion of water. DI is not the same as diabetes me...
Read Article Now Book Mark Article - Hypogonadism (body's sex glands produce little or no hormones)
Hypogonadism
Hypogonadism occurs when the body's sex glands (gonads) produce little or no hormones. In men, these glands are the testes. In women, these glands ...
Read Article Now Book Mark Article - Hypothyroidism (thyroid gland does not make enough thyroid hormone)
Hypothyroidism
Hypothyroidism is a condition in which the thyroid gland does not make enough thyroid hormone. This condition is often called underactive thyroid....
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When to Contact a Medical Professional
Contact your provider if your child has signs of excessive growth.
Prevention
Gigantism cannot be prevented. Early treatment may prevent the disease from getting worse and help avoid complications.
References
Katznelson L, Laws ER Jr, Melmed S, et al; Endocrine Society. Acromegaly: an endocrine society clinical practice guideline. J Clin Endocrinol Metab. 2014;99(11):3933-3951. PMID: 25356808 www.ncbi.nlm.nih.gov/pubmed/25356808/.
Melmed S. Acromegaly. In: Robertson RP, ed. DeGroot's Endocrinology. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 6.
Melmed S. Pituitary masses and tumors. In: Melmed S, Auchus, RJ, Goldfine AB, Koenig RJ, Rosen CJ, eds. Williams Textbook of Endocrinology. 14th ed. Philadelphia, PA: Elsevier; 2020:chap 9.
Endocrine glands - illustration
Endocrine glands release hormones (chemical messengers) into the bloodstream to be transported to various organs and tissues throughout the body. For instance, the pancreas secretes insulin, which allows the body to regulate levels of sugar in the blood. The thyroid gets instructions from the pituitary to secrete hormones which determine the rate of metabolism in the body (the more hormone in the bloodstream, the faster the chemical activity; the less hormone, the slower the activity).
Endocrine glands
illustration
Endocrine glands - illustration
Endocrine glands release hormones (chemical messengers) into the bloodstream to be transported to various organs and tissues throughout the body. For instance, the pancreas secretes insulin, which allows the body to regulate levels of sugar in the blood. The thyroid gets instructions from the pituitary to secrete hormones which determine the rate of metabolism in the body (the more hormone in the bloodstream, the faster the chemical activity; the less hormone, the slower the activity).
Endocrine glands
illustration
Review Date: 5/12/2023
Reviewed By: Sandeep K. Dhaliwal, MD, board-certified in Diabetes, Endocrinology, and Metabolism, Springfield, VA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.