Sunday, October 2, 2011

Polycystic Ovary Syndrome (PCOS) information for patients


What is PCOS?
PCOS is a condition in which a woman’s ovaries and, in some cases the adrenal glands, produce more androgens (a type of hormone) than normal.  High levels of these hormones interfere with the development and release of eggs as part of ovulation.  As a result, fluid-filled sacs or cysts can develop on the ovaries.

Because women with PCOS do not release eggs during ovulation, PCOS is the most common cause of female infertility.

How does PCOS affect fertility?
A woman's ovaries have follicles, which are tiny, fluid-filled sacs that hold the eggs. When an egg is mature, the follicle breaks open to release the egg so it can travel to the uterus for fertilization.

In women with PCOS, immature follicles bunch together to form large cysts or lumps. The eggs mature within the bunched follicles, but the follicles don't break open to release them.

As a result, women with PCOS often have menstrual irregularities, such as amenorrhea (they don’t get menstrual periods) or oligomenorrhea (they only have periods now and then). Because the eggs are not released, most women with PCOS have trouble getting pregnant.

What are the symptoms of PCOS?
In addition to infertility, women with PCOS may also have:
  • Pelvic pain
  • Hirsutism, or excess hair growth on the face, chest, stomach, thumbs, or toes
  • Male-pattern baldness or thinning hair
  • Acne, oily skin, or dandruff
  • Patches of thickened and dark brown or black skin

Also, women who are obese are more likely to have PCOS.

Although it is hard for women with PCOS to get pregnant, some do get pregnant, naturally or using assistive reproductive technology.  Women with PCOS are at higher risk for miscarriage if they do become pregnant.

Women with PCOS are also at higher risk for associated conditions, such as:

  • Diabetes
  • Metabolic syndrome—sometimes called a precursor to diabetes, this syndrome indicates that the body has trouble regulating its insulin
  • Cardiovascular disease—including heart disease and high blood pressure
What is the treatment for PCOS?
There is no cure for PCOS, but many of the symptoms can often be managed. It is important to have PCOS diagnosed and treated early to help prevent associated problems.

There are medications that can help control the symptoms, such as birth control pills to regulate menstruation, reduce androgen levels, and clear acne. Other medications can reduce cosmetic problems, such as hair growth, and control blood pressure and cholesterol.

Lifestyle changes such as regular exercise can aid weight loss and help reduce blood sugar levels and regulate insulin levels more effectively.  Weight loss can help lessen many of the health conditions associated with PCOS and can make symptoms be less severe or even disappear.

Surgical treatment may also be an option, but it is not recommended as the first course of treatment. 

NICHD-funded research has also examined the effects of the anti-diabetes drug metformin on fertility in women with PCOS.  To learn more about this research, check out the news releases about PCOS.

How is PCOS diagnosed?
Your health care provider will take a medical history and do a pelvic exam to feel for cysts on your ovaries.  He or she may also do a vaginal ultrasound and recommend blood tests to measure hormone levels.

Other tests may include measuring levels of insulin, glucose, cholesterol, and triglycerides. 

 

Turner Syndrome information for patients


What is Turner syndrome?

Turner syndrome is a chromosomal condition that alters development in females. Women with this condition tend to be shorter than average and are usually unable to conceive a child (infertile) because of an absence of ovarian function. Other features of this condition that can vary among women who have Turner syndrome include: extra skin on the neck (webbed neck), puffiness or swelling (lymphedema) of the hands and feet, skeletal abnormalities, heart defects and kidney problems.

This condition occurs in about 1 in 2,500 female births worldwide, but is much more common among pregnancies that do not survive to term (miscarriages and stillbirths).

Turner syndrome is a chromosomal condition related to the X chromosome. [ghr.nlm.nih.gov]

Researchers have not yet determined which genes on the X chromosome are responsible for most signs and symptoms of Turner syndrome. They have, however, identified one gene called SHOX that is important for bone development and growth. Missing one copy of this gene likely causes short stature and skeletal abnormalities in women with Turner syndrome.

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What are the symptoms of Turner syndrome?

Girls who have Turner syndrome are shorter than average. They often have normal height for the first three years of life, but then have a slow growth rate. At puberty they do not have the usual growth spurt.

Non-functioning ovaries are another symptom of Turner syndrome. Normally a girl's ovaries begin to produce sex hormones (estrogen and progesterone) at puberty. This does not happen in most girls who have Turner syndrome. They do not start their periods or develop breasts without hormone treatment at the age of puberty.

Even though many women who have Turner have non-functioning ovaries and are infertile, their vagina and womb are totally normal.

In early childhood, girls who have Turner syndrome may have frequent middle ear infections. Recurrent infections can lead to hearing loss in some cases.

Girls with Turner Syndrome are usually of normal intelligence with good verbal skills and reading skills. Some girls, however, have problems with math, memory skills and fine-finger movements.

Additional symptoms of Turner syndrome include the following:
  • An especially wide neck (webbed neck) and a low or indistinct hairline.
  • A broad chest and widely spaced nipples.
  • Arms that turn out slightly at the elbow.
  • A heart murmur, sometimes associated with narrowing of the aorta (blood vessel exiting the heart).
  • A tendency to develop high blood pressure (so this should be checked regularly).
  • Minor eye problems that are corrected by glasses.
  • Scoliosis (deformity of the spine) occurs in 10 percent of adolescent girls who have Turner syndrome.
  • The thyroid gland becomes under-active in about 10 percent of women who have Turner syndrome. Regular blood tests are necessary to detect it early and if necessary treat with thyroid replacement
  • Older or over-weight women with Turner syndrome are slightly more at risk of developing diabetes.
  • Osteoporosis can develop because of a lack of estrogen, but this can largely be prevented by taking hormone replacement therapy.

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How is Turner syndrome diagnosed?

A diagnosis of Turner syndrome may be suspected when there are a number of typical physical features observed such as webbed neck, a broad chest and widely spaced nipples. Sometimes diagnosis is made at birth because of heart problems, an unusually wide neck or swelling of the hands and feet.

The two main clinical features of Turner syndrome are short stature and the lack of the development of the ovaries.

Many girls are diagnosed in early childhood when a slow growth rate and other features are identified. Diagnosis sometimes takes place later when puberty does not occur.

Turner syndrome may be suspected in pregnancy during an ultrasound test. This can be confirmed by prenatal testing - chorionic villous sampling or amniocentesis - to obtain cells from the unborn baby for chromosomal analysis. If a diagnosis is confirmed prenatally, the baby may be under the care of a specialist pediatrician immediately after birth.

Diagnosis is confirmed by a blood test, called a karyotype. This is used to analyze the chromosomal composition of the female. More information about this will be discussed in the section "Is Turner syndrome inherited?"

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What is the treatment for Turner syndrome?

During childhood and adolescence, girls may be under the care of a pediatric endocrinologist, who is a specialist in childhood conditions of the hormones and metabolism.

Growth hormone injections are beneficial in some individuals with Turner syndrome. Injections often begin in early childhood and may increase final adult height by a few inches.

Estrogen replacement therapy is usually started at the time of normal puberty, around 12 years to start breast development. Estrogen and progesterone are given a little later to begin a monthly 'period,' which is necessary to keep the womb healthy. Estrogen is also given to prevent osteoporosis.

Babies born with a heart murmur or narrowing of the aorta may need surgery to correct the problem. A heart expert (cardiologist) will assess and follow up any treatment necessary.

Girls who have Turner syndrome are more likely to get middle ear infections. Repeated infections may lead to hearing loss and should be evaluated by the pediatrician. An ear, nose and throat specialist (ENT) may be involved in caring for this health issue.

High blood pressure is quite common in women who have Turner syndrome. In some cases, the elevated blood pressure is due to narrowing of the aorta or a kidney abnormality. However, most of the time, no specific cause for the elevation is identified. Blood pressure should be checked routinely and, if necessary, treated with medication. Women who have Turner syndrome have a slightly higher risk of having an under active thyroid or developing diabetes. This should also be monitored during routine health maintenance visits and treated if necessary.

Regular health checks are very important. Special clinics for the care of girls and women who have Turner syndrome are available in some areas, with access to a variety of specialists. Early preventive care and treatment is very important.

Almost all women are infertile, but pregnancy with donor embryos may be possible.

Having appropriate medical treatment and support allows a woman with Turner syndrome to lead a normal, healthy and happy life.

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Is Turner syndrome inherited?

Turner syndrome is not usually inherited in families. Turner syndrome occurs when one of the two X chromosomes normally found in women is missing or incomplete. Although the exact cause of Turner syndrome is not known, it appears to occur as a result of a random error during the formation of either the eggs or sperm.

Humans have 46 chromosomes, which contain all of a person's genes and DNA. Two of these chromosomes, the sex chromosomes, determine a person's gender. Both of the sex chromosomes in females are called X chromosomes. (This is written as XX.) Males have an X and a Y chromosome (written as XY). The two sex chromosomes help a person develop fertility and the sexual characteristics of their gender.

In Turner syndrome, the girl does not have the usual pair of two complete X chromosomes. The most common scenario is that the girl has only one X chromosome in her cells. Some girls with Turner syndrome do have two X chromosomes, but one of the X chromosomes is incomplete. In another scenario, the girl has some cells in her body with two X chromosomes, but other cells have only one. This is called mosaicism.

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NHGRI Clinical Research on Turner Syndrome

NHGRI is not currently conducting clinical research on Turner syndrome.

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Additional Resources for Turner Syndrome

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Last Updated: September 26, 2011

Prolactinoma information for patients


On this page:

What is a prolactinoma?

A prolactinoma is a benign-noncancerous-tumor of the pituitary gland that produces a hormone called prolactin. Prolactinomas are the most common type of pituitary tumor. Symptoms of prolactinoma are caused by hyperprolactinemia-too much prolactin in the blood-or by pressure of the tumor on surrounding tissues.

Prolactin stimulates the breast to produce milk during pregnancy. After giving birth, a mother’s prolactin levels fall unless she breastfeeds her infant. Each time the baby nurses, prolactin levels rise to maintain milk production.

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What is the pituitary gland?

The pituitary gland, sometimes called the master gland, plays a critical role in regulating growth and development, metabolism, and reproduction. It produces prolactin and other key hormones including

  • growth hormone, which regulates growth
  • adrenocorticotropin (ACTH), which stimulates the adrenal glands to produce cortisol, a hormone important in metabolism and the body's response to stress
  • thyrotropin, which signals the thyroid gland to produce thyroid hormone, also involved in metabolism and growth
  • luteinizing hormone and follicle-stimulating hormone, which regulate ovulation and estrogen and progesterone production in women and sperm formation and testosterone production in men

The pituitary gland sits in the middle of the head in a bony box called the sella turcica. The optic nerves sit directly above the pituitary gland. Enlargement of the gland can cause symptoms such as headaches or visual disturbances. Pituitary tumors may also impair production of one or more pituitary hormones, causing reduced pituitary function, also called hypopituitarism.


The pituitary gland sits in the sella turcica.

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How common is prolactinoma?

Although small benign pituitary tumors are fairly common in the general population, symptomatic prolactinomas are uncommon. Prolactinomas occur more often in women than men and rarely occur in children.

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What are the symptoms of prolactinoma?

In women, high levels of prolactin in the blood often cause infertility and changes in menstruation. In some women, periods may stop. In others, periods may become irregular or menstrual flow may change. Women who are not pregnant or nursing may begin producing breast milk. Some women may experience a loss of libido-interest in sex. Intercourse may become painful because of vaginal dryness.

In men, the most common symptom of prolactinoma is erectile dysfunction. Because men have no reliable indicator such as changes in menstruation to signal a problem, many men delay going to the doctor until they have headaches or eye problems caused by the enlarged pituitary pressing against nearby optic nerves. They may not recognize a gradual loss of sexual function or libido. Only after treatment do some men realize they had a problem with sexual function.

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What causes prolactinoma?

The cause of pituitary tumors remains largely unknown. Most pituitary tumors are sporadic, meaning they are not genetically passed from parents to their children.

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What else causes prolactin to rise?

In some people, high blood levels of prolactin can be traced to causes other than prolactinoma.

Prescription drugs. Prolactin secretion in the pituitary is normally suppressed by the brain chemical dopamine. Drugs that block the effects of dopamine at the pituitary or deplete dopamine stores in the brain may cause the pituitary to secrete prolactin. These drugs include older antipsychotic medications such as trifluoperazine (Stelazine) and haloperidol (Haldol); the newer antipsychotic drugs risperidone (Risperdal) and molindone (Moban); metoclopramide (Reglan), used to treat gastroesophageal reflux and the nausea caused by certain cancer drugs; and less often, verapamil, alpha-methyldopa (Aldochlor, Aldoril), and reserpine (Serpalan, Serpasil), used to control high blood pressure. Some antidepressants may cause hyperprolactinemia, but further research is needed.

Other pituitary tumors. Other tumors arising in or near the pituitary may block the flow of dopamine from the brain to the prolactin-secreting cells. Such tumors include those that cause acromegaly, a condition caused by too much growth hormone, and Cushing's syndrome, caused by too much cortisol. Other pituitary tumors that do not result in excess hormone production may also block the flow of dopamine.

Hypothyroidism. Increased prolactin levels are often seen in people with hypothyroidism, a condition in which the thyroid does not produce enough thyroid hormone. Doctors routinely test people with hyperprolactinemia for hypothyroidism.

Chest involvement. Nipple stimulation also can cause a modest increase in the amount of prolactin in the blood. Similarly, chest wall injury or shingles involving the chest wall may also cause hyperprolactinemia.

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How is prolactinoma diagnosed?

A doctor will test for prolactin blood levels in women with unexplained milk secretion, called galactorrhea, or with irregular menses or infertility and in men with impaired sexual function and, in rare cases, milk secretion. If prolactin levels are high, a doctor will test thyroid function and ask first about other conditions and medications known to raise prolactin secretion. The doctor may also request magnetic resonance imaging (MRI), which is the most sensitive test for detecting pituitary tumors and determining their size. MRI scans may be repeated periodically to assess tumor progression and the effects of therapy. Computerized tomography (CT) scan also gives an image of the pituitary but is less precise than the MRI.

The doctor will also look for damage to surrounding tissues and perform tests to assess whether production of other pituitary hormones is normal. Depending on the size of the tumor, the doctor may request an eye exam with measurement of visual fields.

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How is prolactinoma treated?

The goals of treatment are to return prolactin secretion to normal, reduce tumor size, correct any visual abnormalities, and restore normal pituitary function. In the case of large tumors, only partial achievement of these goals may be possible.

Medical Treatment

Because dopamine is the chemical that normally inhibits prolactin secretion, doctors may treat prolactinoma with the dopamine agonists bromocriptine (Parlodel) or cabergoline (Dostinex). Agonists are drugs that act like a naturally occurring substance. These drugs shrink the tumor and return prolactin levels to normal in approximately 80 percent of patients. Both drugs have been approved by the U.S. Food and Drug Administration for the treatment of hyperprolactinemia. Bromocriptine is the only dopamine agonist approved for the treatment of infertility. This drug has been in use longer than cabergoline and has a well-established safety record.

Nausea and dizziness are possible side effects of bromocriptine. To avoid these side effects, bromocriptine treatment must be started slowly. A typical starting dose is one-quarter to one-half of a 2.5 milligram (mg) tablet taken at bedtime with a snack. The dose is gradually increased every 3 to 7 days as needed and taken in divided doses with meals or at bedtime with a snack. Most people are successfully treated with 7.5 mg a day or less, although some people need 15 mg or more each day. Because bromocriptine is short acting, it should be taken either twice or three times daily.

Bromocriptine treatment should not be stopped without consulting a qualified endocrinologist-a doctor specializing in disorders of the hormone-producing glands. Prolactin levels rise again in most people when the drug is discontinued. In some, however, prolactin levels remain normal, so the doctor may suggest reducing or discontinuing treatment every 2 years on a trial basis.

Cabergoline is a newer drug that may be more effective than bromocriptine in normalizing prolactin levels and shrinking tumor size. Cabergoline also has less frequent and less severe side effects. Cabergoline is more expensive than bromocriptine and, being newer on the market, its long-term safety record is less well defined. As with bromocriptine therapy, nausea and dizziness are possible side effects but may be avoided if treatment is started slowly. The usual starting dose is .25 mg twice a week. The dose may be increased every 4 weeks as needed, up to 1 mg two times a week. Cabergoline should not be stopped without consulting a qualified endocrinologist.

Recent studies suggest prolactin levels are more likely to remain normal after discontinuing long-term cabergoline therapy than after discontinuing bromocriptine. More research is needed to confirm these findings.

In people taking cabergoline or bromocriptine to treat Parkinson's disease at doses more than 10 times higher than those used for prolactinomas, heart valve damage has been reported. Rare cases of valve damage have been reported in people taking low doses of cabergoline to treat hyperprolactinemia. Before starting these medications, the doctor will order an echocardiogram. An echocardiogram is a sonogram of the heart that checks the heart valves and heart function.

Because limited information exists about the risks of long-term, low-dose cabergoline use, doctors generally prescribe the lowest effective dose and periodically reassess the need for continuing therapy. People taking cabergoline who develop symptoms of shortness of breath or swelling of the feet should promptly notify their physician because these may be signs of heart valve damage.

Surgery

Surgery to remove all or part of the tumor should only be considered if medical therapy cannot be tolerated or if it fails to reduce prolactin levels, restore normal reproduction and pituitary function, and reduce tumor size. If medical therapy is only partially successful, it should be continued, possibly combined with surgery or radiation.

Most often, the tumor is removed through the nasal cavity. Rarely, if the tumor is large or has spread to nearby brain tissue, the surgeon will access the tumor through an opening in the skull.

The results of surgery depend a great deal on tumor size and prolactin levels as well as the skill and experience of the neurosurgeon. The higher the prolactin level before surgery, the lower the chance of normalizing serum prolactin. Serum is the portion of the blood used in measuring prolactin levels. In the best medical centers, surgery corrects prolactin levels in about 80 percent of patients with small tumors and a serum prolactin less than 200 nanograms per milliliter (ng/ml). A surgical cure for large tumors is lower, at 30 to 40 percent. Even in patients with large tumors that cannot be completely removed, drug therapy may be able to return serum prolactin to the normal range-20 ng/ml or less-after surgery. Depending on the size of the tumor and how much of it is removed, studies show that 20 to 50 percent will recur, usually within 5 years.

Because the results of surgery are so dependent on the skill and knowledge of the neurosurgeon, a patient should ask the surgeon about the number of operations he or she has performed to remove pituitary tumors and for success and complication rates in comparison to major medical centers. The best results come from surgeons who have performed hundreds or even thousands of such operations. To find a surgeon, contact The Pituitary Society (see For More Information).

Radiation

Rarely, radiation therapy is used if medical therapy and surgery fail to reduce prolactin levels. Depending on the size and location of the tumor, radiation is delivered in low doses over the course of 5 to 6 weeks or in a single high dose. Radiation therapy is effective about 30 percent of the time.

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How does prolactinoma affect pregnancy?

If a woman has a small prolactinoma, she can usually conceive and have a normal pregnancy after effective medical therapy. If she had a successful pregnancy before, the chance of her having more successful pregnancies is high.

A woman with prolactinoma should discuss her plans to conceive with her physician so she can be carefully evaluated prior to becoming pregnant. This evaluation will include an MRI scan to assess the size of the tumor and an eye examination with measurement of visual fields. As soon as a woman is pregnant, her doctor will usually advise her to stop taking bromocriptine or cabergoline. Although these drugs are safe for the fetus in early pregnancy, their safety throughout an entire pregnancy has not been established. Many doctors prefer to use bromocriptine in patients who plan to become pregnant because it has a longer record of safety in early pregnancy than cabergoline.

The pituitary enlarges and prolactin production increases during pregnancy in women without pituitary disorders. Women with prolactin-secreting tumors may experience further pituitary enlargement and must be closely monitored during pregnancy. Less than 3 percent of pregnant women with small prolactinomas have symptoms of tumor growth such as headaches or vision problems. In women with large prolactinomas, the risk of symptomatic tumor growth is greater, and may be as high as 30 percent.

Most endocrinologists see patients every 2 months throughout the pregnancy. A woman should consult her endocrinologist promptly if she develops symptoms of tumor growth-particularly headaches, vision changes, nausea, vomiting, excessive thirst or urination, or extreme lethargy. Bromocriptine or, less often, cabergoline treatment may be reinitiated and additional treatment may be required if the woman develops symptoms during pregnancy.

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How do oral contraceptives and hormone replacement therapy affect prolactinoma?

Oral contraceptives are not thought to contribute to the development of prolactinomas, although some studies have found increased prolactin levels in women taking these medications. Because oral contraceptives may produce regular menstrual bleeding in women who would otherwise have irregular menses due to hyperprolactinemia, prolactinoma may not be diagnosed until women stop oral contraceptives and find their menses are absent or irregular. Women with prolactinoma treated with bromocriptine or cabergoline may safely take oral contraceptives. Similarly, postmenopausal women treated with medical therapy or surgery for prolactinoma may be candidates for estrogen replacement therapy.

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Is osteoporosis a risk in women with high prolactin levels?

Women whose ovaries produce inadequate estrogen are at increased risk for osteoporosis. Hyperprolactinemia can reduce estrogen production. Although estrogen production may be restored after treatment for hyperprolactinemia, even a year or 2 without estrogen can compromise bone strength. Women should protect themselves from osteoporosis by increasing exercise and calcium intake through diet or supplements and by not smoking. Women treated for hyperprolactinemia may want to have periodic bone density measurements and discuss estrogen replacement therapy or other bone-strengthening medications with their doctor.

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Points to Remember

  • A prolactinoma is a benign tumor of the pituitary gland that produces the hormone prolactin. Prolactin stimulates the breast to produce milk during pregnancy.
  • In women, high levels of prolactin in the blood often cause infertility and changes in menstruation. Women who are not pregnant or nursing may begin producing breast milk. In men, the most common symptom of prolactinoma is erectile dysfunction.
  • Prolactinoma is diagnosed through a blood test. Additional tests rule out other causes of high prolactin levels, such as medications or thyroid problems. Magnetic resonance imaging (MRI) is then used to detect pituitary tumors and determine their size.
  • The first line of treatment is usually medication to shrink the tumor and return prolactin levels to normal. Sometimes surgery or radiation may be necessary.
  • Women with prolactinoma should be carefully evaluated before becoming pregnant and monitored during pregnancy by an endocrinologist.

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Hope through Research

Researchers are working to identify a gene or genes that may contribute to the development of pituitary tumors, including sporadic tumors. They are also investigating certain side effects of long-term treatment for prolactinomas with cabergoline.

Participants in clinical trials can play a more active role in their own health care, gain access to new research treatments before they are widely available, and help others by contributing to medical research. For information about current studies, visit www.ClinicalTrials.gov.

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For More Information

American Association of Clinical Endocrinologists
245 Riverside Avenue, Suite 200
Jacksonville, FL 32202
Phone: 904-353-7878
Fax: 904-353-8185
Internet: www.aace.com

The Endocrine Society
8401 Connecticut Avenue, Suite 900
Chevy Chase, MD 20815-5817
Phone: 1-888-363-6274 or 301-941-0200
Fax: 301-941-0259
Internet: www.endo-society.org

The Pituitary Society
VA Medical Center
423 East 23rd Street, Room 16048aW
New York, NY 10010
Phone: 212-263-6772
Fax: 212-447-6219
Internet: www.pituitarysociety.org

You may also find additional information about this topic by visiting MedlinePlus at www.medlineplus.gov.

This publication may contain information about medications. When prepared, this publication included the most current information available. For updates or for questions about any medications, contact the U.S. Food and Drug Administration toll-free at 1-888-INFO-FDA (1-888-463-6332) or visit www.fda.gov. Consult your doctor for more information.

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Acknowledgments

Publications produced by the NIDDK are carefully reviewed by both NIDDK scientists and outside experts. This publication was reviewed by Michael O. Thorner, M.B., D.Sc., University of Virginia Health System, and Shlomo Melmed, M.D., Cedars-Sinai Health System.

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National Endocrine and Metabolic Diseases Information Service

6 Information Way
Bethesda, MD 20892–3569
Phone: 1–888–828–0904
TTY: 1–866–569–1162
Fax: 703–738–4929
Email: endoandmeta@info.niddk.nih.gov
Internet: www.endocrine.niddk.nih.gov

The National Endocrine and Metabolic Diseases Information Service is an information dissemination service of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). The NIDDK is part of the National Institutes of Health, which is part of the U.S. Department of Health and Human Services.

The NIDDK conducts and supports biomedical research. As a public service, the NIDDK has established information services to increase knowledge and understanding about health and disease among patients, health professionals and the public.

This publication is not copyrighted. The NIDDK encourages users of this publication to duplicate and distribute as many copies as desired.


NIH Publication No. 09-3924
May 2009

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The National Endocrine and Metabolic Diseases Information Service is a service of the National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health.

National Endocrine and Metabolic Diseases Information Service
6 Information Way
Bethesda, MD 20892-3569
Phone: 1-888-828-0904
TTY: 1-866-569-1162
Fax: 1-703-738-4929
Email: endoandmeta@info.niddk.nih.gov
Internet: www.endocrine.niddk.nih.gov

             

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Hashimotos Disease Information for patients

What is Hashimoto's disease?

What is Hashimoto's disease?

Hashimoto's disease, also called chronic lymphocytic thyroiditis or autoimmune thyroiditis, is a form of chronic inflammation of the thyroid gland. The inflammation results in damage to the thyroid gland and reduced thyroid function or "hypothyroidism," meaning the gland doesn't make enough thyroid hormone for the needs of the body. Hashimoto's disease is the most common cause of hypothyroidism in the United States.

The thyroid is a small, butterfly-shaped gland in the front of the neck below the larynx, or voice box. The thyroid gland makes two thyroid hormones, triiodothyronine (T3) and thyroxine (T4). Thyroid hormones circulate throughout the body in the bloodstream and act on virtually every tissue and cell in the body. These hormones affect metabolism, brain development, breathing, heart rate, nervous system functions, body temperature, muscle strength, skin moisture levels, menstrual cycles, weight, cholesterol levels, and more.

Thyroid hormone production is regulated by another hormone called thyroid-stimulating hormone (TSH). TSH is made by the pituitary gland, a pea-sized gland located in the brain. When thyroid hormone levels in the blood are low, the pituitary releases more TSH. When thyroid hormone levels are high, the pituitary responds by dropping TSH production.


The thyroid gland's production of thyroid hormones (T3 and T4) is triggered by thyroid-stimulating hormone (TSH), which is made by the pituitary gland.

Hashimoto's disease is an autoimmune disorder, meaning the body's immune system attacks its own healthy cells and tissues. In Hashimoto's disease, the immune system makes antibodies that attack cells in the thyroid and interfere with their ability to produce thyroid hormone. Large numbers of white blood cells called lymphocytes accumulate in the thyroid. Lymphocytes make the antibodies that drive the autoimmune process.

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What are the symptoms of Hashimoto's disease?

Many people with Hashimoto's disease have no symptoms at first. As the disease slowly progresses, the thyroid usually enlarges and may cause the front of the neck to look swollen. The enlarged gland, called a goiter, may create a feeling of fullness in the throat but is usually not painful. After years, or even decades, the damage to the thyroid causes it to shrink and the goiter to disappear.

Not everyone with Hashimoto's disease develops hypothyroidism. For those who do, the hypothyroidism may be subclinical—mild and without symptoms. Other people have one or more of these common symptoms of hypothyroidism:

  • fatigue
  • weight gain
  • cold intolerance
  • joint and muscle pain
  • constipation
  • dry, thinning hair
  • heavy or irregular menstrual periods and impaired fertility
  • depression
  • a slowed heart rate

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Who is likely to develop Hashimoto's disease?

Hashimoto's disease is about seven times more common in women than men. Although it often occurs in adolescent or young women, the disease more commonly appears between 40 and 60 years of age.1 Hashimoto's disease tends to run in families. Scientists are working to identify the gene or genes that cause the disease to be passed from one generation to the next. Possible environmental influences are also being studied. For example, researchers have found that excess iodine consumption may inhibit thyroid hormone production in susceptible individuals. Certain drugs or viral infections may also contribute to autoimmune thyroid diseases.

People with other autoimmune disorders are more likely to develop Hashimoto's disease and vice versa. These disorders include

  • vitiligo, a condition in which some areas of the skin lose their natural color
  • rheumatoid arthritis
  • Addison's disease, in which the adrenal glands are damaged and cannot produce enough of certain critical hormones
  • type 1 diabetes
  • pernicious anemia, a type of anemia caused by inadequate vitamin B12 in the body

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How is Hashimoto's disease diagnosed?

Diagnosis begins with a physical examination and medical history. An enlarged thyroid gland may be detectable during a physical exam and symptoms may suggest hypothyroidism. Doctors will then do several blood tests to confirm the diagnosis.

The ultrasensitive TSH test is usually the first test performed. This blood test is the most accurate measure of thyroid activity available. Generally, a TSH reading above normal means a person has hypothyroidism. In people who produce too little thyroid hormone, the pituitary makes TSH continuously, trying to get the thyroid to produce more thyroid hormone.

The T4 test measures the actual amount of circulating thyroid hormone in the blood. In subclinical hypothyroidism, the level of T4 in the blood is normal, but as the disease progresses, T4 levels drop below normal.

The antithyroid peroxidase (anti-TPO) antibody test looks for the presence of thyroid autoantibodies. Most people with Hashimoto's disease have these antibodies, but people whose hypothyroidism is caused by other conditions do not.

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How is Hashimoto's disease treated?

Treatment generally depends on whether the thyroid is damaged enough to cause hypothyroidism. In the absence of hypothyroidism, some doctors treat Hashimoto’s disease to reduce the size of the goiter. Others choose not to treat the disease and simply monitor their patients for disease progression.

Hashimoto's disease, with or without hypothyroidism, is treated with synthetic thyroid hormone. Doctors prefer to use synthetic T4 such as Synthroid rather than synthetic T3 because T4 stays in the body longer, ensuring a steady supply of thyroid hormone throughout the day. The so-called "natural" thyroid preparations made with desiccated animal thyroid are rarely prescribed today.

The exact dose of synthetic thyroid hormone depends on a person's age and weight; the severity of the hypothyroidism, if present; the presence of other health problems; and the use of other medications such as cholesterol-lowering drugs that could interfere with the action of synthetic thyroid hormone.

Doctors routinely test the blood of patients taking synthetic thyroid hormone and make dosage adjustments as necessary. A normal, healthy thyroid and metabolic state can be restored with the use of synthetic thyroid hormone.

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Points to Remember

  • Hashimoto's disease is an autoimmune disease that causes chronic inflammation of the thyroid gland.

  • Hashimoto's disease is the most common cause of hypothyroidism- when the thyroid gland doesn't make enough thyroid hormone for the body's needs-in the United States and most often affects women between the ages of 40 and 60.

  • Symptoms of Hashimoto's disease may include goiter, a feeling of fullness in the throat, fatigue, weight gain, cold intolerance, and a slowed heart rate.

  • Hashimoto's disease may not always need treatment. When it does, it is treated with synthetic thyroid hormone.

For more information about hypothyroidism, see the National Endocrine and Metabolic Diseases Information Service's fact sheet Hypothyroidism.

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Hope through Research

Researchers are working to identify the genes that make some people susceptible to autoimmune thyroid diseases. Other studies are examining the cellular activities that trigger lymphocyte invasion of the thyroid and potential therapies to interrupt these processes.

Participants in clinical trials can play a more active role in their own health care, gain access to new research treatments before they are widely available, and help others by contributing to medical research. For information about current studies, visit www.ClinicalTrials.gov.

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For More Information

American Academy of Otolaryngology-Head and Neck Surgery
1650 Diagonal Road
Alexandria, VA 22314-2857
Phone: 703-836-4444
Internet: www.entnet.org

American Association of Clinical Endocrinologists
245 Riverside Avenue, Suite 200
Jacksonville, FL 32202
Phone: 904-353-7878
Fax: 904-353-8185
Email: info@aace.com
Internet: www.aace.com

American Thyroid Association
6066 Leesburg Pike, Suite 550
Falls Church, VA 22041
Phone: 1-800-THYROID (849-7643) or 703-998-8890
Fax: 703-998-8893
Email: admin@thyroid.org
Internet: www.thyroid.org

The Endocrine Society
8401 Connecticut Avenue, Suite 900
Chevy Chase, MD 20815
Phone: 1-888-363-6274 or 301-941-0200
Fax: 301-941-0259
Email: societyservices@endo-society.org
Internet: www.endo-society.org

The Hormone Foundation
8401 Connecticut Avenue, Suite 900
Chevy Chase, MD 20815-5817
Phone: 1-800-HORMONE (467-6663)
Fax: 301-941-0259
Email: hormone@endo-society.org
Internet: www.hormone.org

You may also find additional information about this topic by visiting MedlinePlus at www.medlineplus.gov.

This publication may contain information about medications. When prepared, this publication included the most current information available. For updates or for questions about any medications, contact the U.S. Food and Drug Administration toll-free at 1-888-INFO-FDA (1-888-463-6332) or visit www.fda.gov. Consult your doctor for more information.


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The National Endocrine and Metabolic Diseases Information Service

6 Information Way
Bethesda, MD 20892–3569
Phone: 1–888–828–0904
TTY: 1–866–569–1162
Fax: 1–703–738–4929
Email: endoandmeta@info.niddk.nih.gov
Internet: www.endocrine.niddk.nih.gov