What Is Hashimoto's Thyroiditis?
Hashimoto's thyroiditis is also called,
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Hashimoto's disease.
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Chronic lymphocytic thyroiditis.
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Autoimmune thyroiditis.
Hashimoto's thyroiditis is distinguished by lymphoid infiltration of the thyroid, destroying the thyroid follicles and eventually leading to fibrosis and thyroid enlargement. Hashimoto's disease is the most common cause of hypothyroidism, and the terminology of autoimmune hypothyroidism is confusing as some authorities reserve the term,
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'Hashimoto's Thyroiditis' especially for patients who experience positive antithyroid peroxidase antibodies and a firm goiter who may or may not be hypothyroid.
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'Spontaneous Atrophic Hypothyroidism' for patients with hypothyroidism and having a goiter in whom TSH receptor-blocking antibodies may be more important than anti peroxidase antibodies.
Therefore, both these syndromes are variants of the same underlying illness.
What Are the Causes of Hashimoto's Thyroiditis?
The exact cause is unknown, but the following factors play an important role. They include,
1) Hereditary - It is suggested that a genetic component is present in people with Hashimoto's disease, that is, family members have thyroid disease or other autoimmune diseases like,
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Type 1 diabetes.
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Lupus.
2) Sex Hormones - It is suggested that sex hormones play a major role in Hashimoto's disease affecting about seven times in women compared to men. Also, some women experience thyroid problems during the first year after pregnancy, and this problem usually goes away with time, and as many as 20% of these women may develop Hashimoto's disease years later.
3) Increased Iodine - A trace amount of iodine is required by the body to make thyroid hormones, but certain drugs and excessive iodine trigger thyroid disease.
4) Excessive Radiation Exposure - Increased cases of thyroid diseases are seen in people who are more exposed to radiation.
What Are the Symptoms of Hashimoto's Thyroiditis?
The symptoms of Hashimoto's thyroiditis may not be noticed at first, or it takes years to develop. The first sign of the disease is swelling at the front of the throat, an enlarged thyroid, called a goiter. After years, Hashimoto's thyroiditis typically progresses and results in chronic thyroid damage and a drop in thyroid hormone levels in the blood. The other symptoms include,
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Weight gain.
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Puffiness of the face.
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Hair loss and brittle hair.
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Fatigue.
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Inability to get warm.
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Pale and dry skin.
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Difficulty in getting pregnant.
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Muscle weakness and pain.
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Heavy menstruation.
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Constipation.
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Brittle nails.
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Slow heart rate.
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Enlarged tongue.
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Memory lapses.
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Stiffness of the joints.
What Are the Clinical Features of Hashimoto's Thyroiditis?
1) Anatomy:
The thyroid is a small, butterfly-shaped gland situated in the front of the neck (anterior to the thyroid cartilage) below Adam's apple. Thyroid hormones control the body and can nearly affect every organ in the body, even the heartbeats.
In people with Hashimoto's, the immune system turns against the body's own tissues and attacks the thyroid, and leads to a condition called hypothyroidism, where the thyroid does not make enough hormones for the body.
2) Age and Sex:
Females in the perimenopausal group (40 to 50 years) are commonly affected but can also occur in men and women of any age and can also occur in children.
3) Family History:
There are high chances to develop Hashimoto's disease if other family members have this disease.
4) Incidence:
There is an increase in the incidence of approximately 3 women and 0.8 men per 1000 people each year.
5) Examination:
Many presents with a small or moderately sized diffuse goiter, which is characterized by,
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A firm to hard and sometimes rubbery consistency.
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Smooth or irregular.
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Involve a lobe or the entire gland.
The goiter may be soft, however, and impossible to differentiate from a simple goiter by palpation alone.
6) Pathology:
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Initially, symptoms of mild hyperthyroidism (Hashitoxicosis) may be present. Later, extensive intrathyroidal fibrosis results in permanent hypothyroidism.
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The thyroid follicles are destroyed by significant fibrosis. The deep eosinophilic staining thyroid follicular cell, Askanazy cell, is the characteristic.
7) Laboratory Tests:
In more than 90% of patients with Hashimoto's thyroiditis, the antibodies of antithyroid peroxidase are present in the serum. In those under 20 years, antinuclear factor (ANF) may also be positive. In many cases, thyroid antibodies are raised, suggesting an autoimmune disorder.
What Are the Complications of Hashimoto's Thyroiditis?
Hashimoto's disease leads to a number of health problems, such as:
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Permanent Hypothyroidism - If untreated or unknown, it can lead to permanent hypothyroidism, affecting different parts of the body.
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Enlarged Thyroid Gland (Goiter) - A large goiter can interfere with swallowing and breathing.
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Papillary Carcinoma of the Thyroid - It is the malignant tumor of the thyroid gland affecting the lymph nodes in the lower deep cervical region.
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Heart Disease - Hashimoto's disease increases the risk of heart disease due to high LDL cholesterol levels, which is bad cholesterol occurring in people with hypothyroidism. If left untreated, it can lead to heart failure.
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Mental Health Problems - This disease often leads to depression and slow mental functioning.
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Malignant Lymphoma - Primary thyroid lymphoma occurs in patients with Hashimoto's thyroiditis, where lymphocytes infiltrate the thyroid gland.
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Decrease in Sexual Needs - Decreases the desire of libido both in men and women.
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Myxedema Coma - It is triggered by cold exposure, infection, and systemic illness of the body, and it requires an emergency medical treatment due to its high mortality rate despite intensive treatment.
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Birth Defects - Babies born to untreated hypothyroidism women due to Hashimoto's thyroiditis have increased birth defects like cleft palate when compared to healthy mothers.
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Pregnancy - If planning to get pregnant, check your thyroid levels as there is a link between heart, kidney, and lung problems in infants with hypothyroid pregnancies.
How To Diagnose Hashimoto's Thyroiditis?
Diagnosis is based on signs and symptoms and thyroid hormone and thyroid-stimulating hormone (TSH) levels produced in the pituitary gland. These may include:
Hormone Test:
Hormones produced in the thyroid and pituitary glands can be determined in blood tests. When underactive thyroid, there is a low level of thyroid hormone and a high level of TSH because the pituitary gland stimulates more production of thyroid hormone.
Antibody Test:
Abnormal antibodies are diagnosed in this autoimmune disease. TPO enzyme is usually found in the thyroid gland and plays a vital role in producing thyroid hormones. Antibodies against TPO are not positive for everyone with Hashimoto's thyroiditis because this antibody is sometimes present even in goiter, hypothyroidism cases.
TSH Test:
Before, we could not detect hypothyroidism until symptoms were predicted, but now sensitive TSH screening tests help diagnose the disease earlier, even before you experience symptoms.
TSH is checked first, followed by a thyroid hormone test if needed. TSH tests help in managing hypothyroidism and determine the right dosage of medication.
What Are the Treatment Options of Hashimoto's Thyroiditis?
Treatment for Hashimoto's disease is a wait-and-see approach that involves observation and use of medications according to thyroid functioning.
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When this disease causes thyroid hormone deficiency, Levothyroxine therapy is indicated as a treatment for hypothyroidism and also to shrink an associated goiter.
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Thyroxine is given as a supplementary dose.
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The given dose of thyroxine should be sufficient to reduce the levels of thyroid-stimulating hormone (TSH).
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If the goiter is big and causing discomfort, a subtotal thyroidectomy can also be done.
