Pseudohypoparathyroidism
Albright hereditary osteodystrophy; Types 1A and 1B pseudohypoparathyroidism; PHP
Pseudohypoparathyroidism (PHP) is a genetic disorder in which the body fails to respond to parathyroid hormone .
Parathyroid hormone
The PTH test measures the level of parathyroid hormone in the blood. PTH stands for parathyroid hormone. It is a protein hormone released by the par...
A related condition is hypoparathyroidism , in which the body does not make enough parathyroid hormone.
Hypoparathyroidism
Hypoparathyroidism is a disorder in which the parathyroid glands in the neck do not produce enough parathyroid hormone (PTH).
Causes
The parathyroid glands produce parathyroid hormone (PTH). PTH helps control calcium, phosphorus, and vitamin D levels in the blood and bone.
If you have PHP, your body produces the right amount of PTH, but is "resistant" to its effect. This causes low blood calcium levels and high blood phosphate levels.
PHP is caused by abnormal genes. There are different types of PHP. All forms are rare.
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Type Ia is inherited in an
autosomal dominant manner
. That means only one parent needs to pass you the faulty gene for you to have the condition. It is also called Albright hereditary osteodystrophy. The condition causes short stature, round face, obesity, developmental delay, and short hand bones. Symptoms depend on whether you inherit the gene from your mother or father.
Autosomal dominant manner
Autosomal dominant is one of several ways that a trait or disorder can be passed down (inherited) through families. In an autosomal dominant disease,...
- Type Ib involves resistance to PTH only in the kidneys. Less is known about type Ib than type Ia. Calcium in the blood is low, but there are no symptoms of Albright hereditary osteodystrophy.
- Type II also involves low blood calcium and high blood phosphate levels. People with this form do not have the physical traits common to people with Type Ia. The genetic abnormality that causes it is not known.
Symptoms
Symptoms are related to a low level of calcium and include:
- Cataracts
- Dental problems
- Numbness
- Seizures
- Tetany (a collection of symptoms including muscle twitches and hand and foot spasms)
People with Albright hereditary osteodystrophy may have the following symptoms:
- Calcium deposits under the skin
- Dimples that can replace knuckles on affected fingers
- Round face and short neck
- Short hand bones, especially the bone below the 4th finger
- Short height
Exams and Tests
Blood tests will be done to check calcium, phosphorus , and PTH levels. You may also need urine tests.
Phosphorus
The phosphorus blood test measures the amount of phosphate in the blood.
Other tests may include:
- Genetic testing
-
Head MRI
or
CT scan of the brain
Head MRI
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...
CT scan of the brain
A head computed tomography (CT) scan uses many x-rays to create pictures of the head, including the skull, brain, eye sockets, and sinuses.
Treatment
Your health care provider will recommend calcium and vitamin D supplements to maintain a proper calcium level. If the blood phosphate level is high, you may need to follow a low-phosphorus diet or take medicines called phosphate binders (such as calcium carbonate or calcium acetate).
Outlook (Prognosis)
Low blood calcium in PHP is usually milder than in other forms of hypoparathyroidism.
Possible Complications
People with type Ia PHP are more likely to have other endocrine system problems (such as hypothyroidism and hypogonadism ).
Hypothyroidism
Hypothyroidism is a condition in which the thyroid gland does not make enough thyroid hormone. This condition is often called underactive thyroid....
Hypogonadism
Hypogonadism occurs when the body's sex glands produce little or no hormones. In men, these glands (gonads) are the testes. In women, these glands ...
PHP may be connected to other hormone problems, resulting in:
- Low sex drive
- Slow sexual development
- Low energy levels
- Weight gain
When to Contact a Medical Professional
Contact your provider if you or your child have any symptoms of a low calcium level or pseudohypoparathyroidism.
References
Bastepe M, Juppner H. Pseudohypoparathyroidism, Albright's hereditary osteodystrophy, and progressive osseous heteroplasia. In: Jameson JL, De Groot LJ, de Kretser DM, et al, eds. Endocrinology: Adult and Pediatric . 7th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 66.
Doyle DA. Pseudohypoparathyroidism (Albright hereditary osteodystrophy). In: Kliegman RM, Stanton BF, St Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics. 20th ed. Philadelphia, PA: Elsevier; 2016:chap 572.
Thakker RV. The parathyroid glands, hypercalcemia and hypocalcemia. In: Goldman L, Schafer AI, eds.
Goldman's Cecil Medicine.
25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 245.
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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 pace of chemical activity in the body (the more hormone in the bloodstream, the faster the chemical activity; the less hormone, the slower the activity).
Endocrine glands
illustration
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Parathyroid glands - illustration
The 4 parathyroid glands are located near or attached to the back side of the thyroid gland and produce pararthyroid hormone (PTH). Parathyroid hormone regulates calcium, phosphorus, and magnesium balance within the blood and bone by maintaining a balance between the mineral levels in the blood and the bone.
Parathyroid 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 pace of chemical activity in the body (the more hormone in the bloodstream, the faster the chemical activity; the less hormone, the slower the activity).
Endocrine glands
illustration
-
Parathyroid glands - illustration
The 4 parathyroid glands are located near or attached to the back side of the thyroid gland and produce pararthyroid hormone (PTH). Parathyroid hormone regulates calcium, phosphorus, and magnesium balance within the blood and bone by maintaining a balance between the mineral levels in the blood and the bone.
Parathyroid glands
illustration
Review Date: 5/2/2016
Reviewed By: Brent Wisse, MD, Associate Professor of Medicine, Division of Metabolism, Endocrinology & Nutrition, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.