Hashimoto s Disease BY: NADIA, ZAYNEB, OLA AND NIKI CLASS: 10A

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1 Hashimoto s Disease BY: NADIA, ZAYNEB, OLA AND NIKI CLASS: 10A

2 What is Hashimoto s Disease? Hashimoto's thyroiditis or chronic lymphocytic thyroiditis is an autoimmune disease in which the thyroid gland is attacked by a variety of cell- and antibody-mediated immune processes, causing primary hypothyroidism. It was the first disease to be recognized as an autoimmune disease. It was first described by the Japanese specialist Hakaru Hashimoto.

3 Signs and symptoms There are many symptoms that are attributed to Hashimoto's thyroiditis or Hashimoto's disease. The most common symptoms include the following: fatigue, weight gain, pale or puffy face, feeling cold, joint and muscle pain, constipation, dry and thinning hair, heavy menstrual flow or irregular periods, depression, panic disorder, a slowed heart rate, and problems getting pregnant and maintaining pregnancy. Hashimoto s disease is about seven times more common in women than in men. It can occur in teens and young women, but more commonly shows up in middle age, particularly for men. People who get Hashimoto s disease often have family members who have thyroid or other autoimmune diseases, and sometimes have other autoimmune diseases themselves. The thyroid gland may become firm, large, and lobulated in Hashimoto's thyroiditis, but changes in the thyroid can also be nonpalpable. Enlargement of the thyroid is due tolymphocytic infiltration and fibrosis rather than tissue hypertrophy.

4 Diagnosis Diagnosis is usually made by detecting elevated levels of anti-thyroid peroxidase antibodies in the serum, but seronegative (without circulating autoantibodies) thyroiditis is also possible. Given the relatively non-specific symptoms of initial hypothyroidism, Hashimoto's thyroiditis is often misdiagnosed as depression, cyclothymia, PMS, chronic fatigue syndrome, fibromyalgia and, less frequently, as ED or an anxiety disorder. On gross examination, there is often presentation of a hard goitre that is not painful to the touch; other symptoms seen with hypothyroidism, such as periorbital myxedema, depend on the current state of progression of the response, especially given the usually gradual development of clinically relevant hypothyroidism. Testing for thyroid-stimulating hormone (TSH), free T3, free T4, and the anti-thyroglobulin antibodies (anti-tg), anti-thyroid peroxidase antibodies (anti-tpo) and antimicrosomal antibodies can help obtain an accurate diagnosis. Earlier assessment of the patient may present with elevated levels of thyroglobulin owing to transient thyrotoxicosis, as inflammation within the thyroid causes damage to the integrity of thyroid follicle storage of thyroglobulin; TSH is increased as the pituitary tries to compensate for decreased T4

5 This exposure of the body to substantial amounts of previously isolated thyroid enzymes is thought to contribute to the exacerbation of tolerance breakdown, giving rise to the more pronounced symptoms seen later in the disease. Lymphocytic infiltration of the thyrocyte-associated tissues often leads to the histologically significant finding of germinal center development within the thyroid gland. Hashimoto's when presenting as mania is known as Prasad's syndrome after Ashok Prasad, the psychiatrist who first described it.

6 Treatment: Managing hormone levels Hypothyroidism caused by Hashimoto's thyroiditis is treated with thyroid hormone replacement agents such as levothyroxine,triiodothyronine or desiccated thyroid extract. A tablet taken once a day generally keeps the thyroid hormone levels normal. In most cases, the treatment needs to be taken for the rest of the patient's life. In the event that hypothyroidism is caused by Hashimoto's thyroiditis, it is recommended that the TSH levels be kept under 3.0.

7 Treatment: Selenium Although the current clinical practice guidelines for hypothyroidism in adults do not indicate selenium supplementation.a 1-year study of 46 patients found supplementing 80 μg per day of selenium slowed several markers of disease progression. Another study comparing 100 μg and 200 μg doses of selenium combined with levothyroxine in 88 female patients over 9 months found that 200 μg was more effective. A 2013 systemic review found there is still not enough evidence to definitively support or refute the efficacy of selenium for Hashimoto's thyroiditis, and urges more clinical trials are needed before efficacy can be proven. As a dietary supplement, the FDA recommends at least 55 μg per day of selenium for adults with a tolerable upper intake level of 400 μg

8 Treatment: Low-level laser therapy According to a study published in 2013, near-infrared low level laser therapy has been shown to be effective in phase two clinical trials at improving thyroid function.

9 Treatment: Gluten-free diet Preliminary studies have suggested a correlation between Hashimoto's thyroiditis and celiac disease. While it has not been rigorously explored, there are anecdotal reports that a gluten-free diet may reduce the autoimmune response responsible for thyroid degeneration] A study published in January 2012 compared a group of confirmed celiac patients to a control group of healthy individuals, starting a gluten-free diet and continuing for one year. While there was a higher occurrence of thyroiditis found amongst the celiac group, there was no reduction in their level of anti-tpo antibody, improvement in thyroid function, or change in thyroid volume reduction after one year without gluten. The study mentions that its results disagree with other studies, such as a prospective study published in August 2000 with 90 celiac patients, which found that thyroid-related serum antibodies tended to reduce during a gluten-free diet.

10 Epidemiology This disorder is believed to be the most common cause of primary hypothyroidism in North America; as a cause of non-endemic goiter, it is among the most common. An average of 1 to 1.5 in 1000 people have this disease. It occurs between eight and fifteen times more often in women than in men. Though it may occur at any age, including in children, it is most often observed in women between 30 and 60 years of age. It is more common in regions of high iodine dietary intake, and among people who are genetically susceptible.

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