Generally it is asymptomatic in mild and moderate disease conditions but the symptoms are noticeable as the condition worsens. Some common symptoms are mentioned below [7]:

• Nervous system: Depression, dementia, and other psychiatric disturbances, memory loss, sleep apnea, daytime somnolence, mild nerve deafness and peripheral neuropathy
• Gastrointestinal system: Constipation
• Musculoskeletal system: Joint pains and muscle cramps
• Cardiovasular system: Bradycardia
• Reproductive system: Irregular menstrual cycle
• Others: Dry skin, weight gain, cold intolerance, voice hoarseness, pressure symptoms in the neck from thyroid enlargement, galactorrhea, fatigue, weight gain, puffy face and hair thinning

• Goiter

  What is a goiter? Another manifestation of Hashimoto's is a goiter, which appears as a swelling in the front of the neck. A lack of iodine is a common cause of goiter in places where there is not enough iodine in the diet. [medicalnewstoday.com]

  A clearly enlarging goiter was observed before the diagnosis of lymphoma in 3 patients. [ncbi.nlm.nih.gov]

  Treatment For patients with thyroid enlargement (goiter) or hypothyroidism, thyroid hormone therapy is clearly needed, since proper dosage corrects any symptoms due to thyroid hormone deficiency and may decrease the goiter’s size. [thyroidawareness.com]

  Goiter Symptoms associated with goiter include: Painless swelling of the thyroid gland in the front of the neck Difficulty breathing Difficulty swallowing. [innerbody.com]

  Not everyone with thyroiditis or goiter has low levels of thyroid hormone. You may just need regular follow-up by a health care provider. The disease stays stable for years. [medlineplus.gov]

• Weight Gain

  Symptoms Common symptoms of the disease are dry skin, weight gain, cold intolerance, voice hoarseness, pressure symptoms in the neck from thyroid enlargement, tiredness, weight gain and hair thinning. [symptoma.com]

  “Hashimoto’s can often be associated with some weight gain — it’s mostly salt and water weight, which is why you look puffy,” she says. [health.clevelandclinic.org]

  A 16-year-old girl with a four-year history of AN presented with elevated TSH that fluctuated with changes in weight. TSH was within normal limits (1.7-3.64 mIU/L) following periods of weight loss and elevated with weight gain (5.9-21.66 mIU/L). [ncbi.nlm.nih.gov]

  Low thyroid hormone levels may cause a range of symptoms, such as tiredness, weight gain and intolerance to cold temperatures. Your thyroid gland may become noticeably larger - this is called a goitre. Or it may shrink. [healthdirect.gov.au]

• Fatigue

  Three patients on thyroid hormone replacement because of Hashimoto's thyroiditis were treated for the fatigue component of the disease from May to July 2011. Fatigue was measured using the Fatigue Severity Scale. [ncbi.nlm.nih.gov]

  If fatigue persists, let your doctor know so they can help rule out other conditions that cause fatigue — such as sleep apnea, which is often undiagnosed. 4. Thyroid medication only works if taken the right way. [health.clevelandclinic.org]

  Hyperthyroidism can cause sweating, rapid heart rate, anxiety, tremors, fatigue, difficulty sleeping, sudden weight loss, and protruding eyes. Hypothyroidism can cause weight gain, fatigue, dry skin, hair loss, intolerance to cold, and constipation. [en.wikipedia.org]

  Fatigue improved to the point that it was comparable to the normal Norwegian population. [health.harvard.edu]

• Thyroid Nodule

  In the differential diagnosis of thyroid nodules, ultrasound-guided fine-needle biopsy is an effective method to distinguish Hashimoto's thyroiditis from other thyroid disorders. [ncbi.nlm.nih.gov]

  Although the patient was referred to us with a diagnosis of concerning thyroid nodules, her ultrasound revealed diffuse thyroiditis without evidence of any nodules. Therefore the prior nodules found on ultrasound were in fact "pseudo nodules". [thyroidcancer.com]

• Myxedema

  Myxedema coma: In its severest form, untreated hypothyroidism may result in a rare life-threatening condition called myxedema or myxedema coma. There is mental slowing, profound lethargy, and ultimately coma. This is a life-threatening emergency. [emedicinehealth.com]

  Myxedema Severe untreated hypothyroidism leads to myxedema, a condition characterized by the following: Heart failure Seizures Loss of consciousness Death. [innerbody.com]

  Abstract Myxedema coma (MC) is a rare, but often fatal endocrine emergency. The majority of cases that occur in elderly women with long-standing primary hypothyroidism are caused by particular triggers. [ncbi.nlm.nih.gov]

  A myxedema coma may be triggered by exposure to cold, sedatives, infection or other stress on your body. Myxedema requires immediate emergency medical treatment. Birth defects. [mayoclinic.org]

  […] costal areas  Diagnosis ◦ Low FT4, High TSH (Primary, check for antibodies) ◦ Low FT4, Low TSH (Secondary or Tertiary, TRH stimulation test, MRI)  Treatment ◦ Levothyroxine (T4) due to longer half life ◦ Treatment prevents bone loss, cardiomyopathy, myxedema [slideshare.net]

• Hoarseness

  Symptoms Common symptoms of the disease are dry skin, weight gain, cold intolerance, voice hoarseness, pressure symptoms in the neck from thyroid enlargement, tiredness, weight gain and hair thinning. [symptoma.com]

  Anyone who has a hoarse voice, constipation, a puffy and pale face, dry skin, and feels tired for no clear reason should see a doctor. Causes Hashimoto's disease is an inflammation of the thyroid gland. [medicalnewstoday.com]

  These include: feeling tired and sleepy all the time finding it hard to concentrate feeling cold even in a warm place dry and coarse hair dry and thinning hair a hoarse or croaky voice muscle weakness, cramps and aches pins and needles in the fingers [btf-thyroid.org]

• Arthralgia

  We report on a 59-year-old man with a 1-year history of forearm erythema, bilateral limb arthralgia, and muscle weakness. During the initial examination we observed infiltrative erythema of the forearm and muscle weakness and atrophy of the limbs. [ncbi.nlm.nih.gov]

  Hashimoto’s thyroiditis is often associated with arthralgia, myalgia, can lead to myopathy. [physio-pedia.com]

• Alopecia

  Alopecia areata is an autoimmune disease associated with other autoimmune diseases such as thyroid disorders, anemia, and other skin disorders. [ncbi.nlm.nih.gov]

  HT is associated with other autoimmune diseases such as alopecia, vitiligo, coeliac disease, addison disease, type 1 diabetes and polyglandular syndrome. [atif.sobiad.com]

  Accordingly, when comparing median age at diagnosis between cases with different NTADs, patients with coexisting arthropathies and/or connective diseases were significantly older compared with those reporting T1DM, vitiligo, alopecia or CD. [eje.bioscientifica.com]

  There is often hair loss (alopecia) and the skin becomes dry and flaky. [endocrinesurgeon.co.uk]

• Urticaria

  In this case report we describe a 49 year-old man who presented with chronic urticaria, angioedema and soft stool consistency. [ncbi.nlm.nih.gov]

  Leslie J De Groot,MD Second Response BY DR ANTHONY WEETMAN -My understanding is that chronic urticaria has been reported to be more frequent in autoimmune thyroid disease and thyroid antibodies occur in up to 27% of patients with urticaria (J Allergy [endotext.org]

  0.062  Polymyositis 1 (0.2%) 0  Systemic scleroderma (SSc) 1 (0.2%) 0  Undifferentiated connective disease 10 (2%) 0 0.017  Vasculitis 1 (0.2%) 1 (0.18%) 0.636 Cutaneous diseases 29 (5.8%) 25 (4.5%) 0.507  Vitiligo 14 (2.8%) 15 (2.7%) 0.319  Chronic urticaria [eje.bioscientifica.com]

  The AITD may also be associated with chronic urticaria 26 and, rarely, glomerulonephritis. 27 Clinical Manifestations Thyroid hormones play an important role in childhood growth and are involved in the maturation and metabolism of certain organs such [touchendocrinology.com]

• Neck Mass

  A 47-year-old Filipino woman with a 30-year history of an asymptomatic anterior neck mass developed painful, erythematous annular plaques on her arms with associated fever. Skin biopsy confirmed the diagnosis of Sweet's syndrome. [ncbi.nlm.nih.gov]

  A large neck mass (10 cm) was visible, predominantly on the right side (fig 1⇓). Her systems examinations were normal and she had no palpable lymphadenopathy. [bmj.com]

  Hashimoto thyroiditis manifesting as a solitary cold nodule in a 34-year-old woman who complained of a palpable right-sided neck mass of 5 months duration. At physical examination, the nodule felt very firm. [pubs.rsna.org]

• Neck Swelling

  She was advised to take thyroxine tablets (100 µg) daily, and after two months her neck swelling reduced in size and her serum TSH concentration normalised (1.2 mU/L). [bmj.com]

  We report a case of a 56-year-old Portuguese man who presented with a one-month history of progressive neck swelling and dysphagia. [ncbi.nlm.nih.gov]

  We report a case of 45-year-old male, with left sided painless neck swelling, with a purulent discharging sinus over it associated with night sweats and loss of appetite. [hindawi.com]

  CASE 48 yrs; Female Midline neck swelling,painless & diffuse, gradually increasing in size x2mths Fatigue, depression, constipation, wt gain, cold intolerance, dry &coarse hair and skin. 3. [slideshare.net]

• Facial Edema

  Physical findings may include: Cold and dry skin Facial edema particularly periorbital, as well as nonpitting edema involving the hands and feet Brittle nails Bradycardia The delayed relaxation phase of tendon reflexes Elevated blood pressure Slow speech [ncbi.nlm.nih.gov]

• Loss of Libido

  Depression, dementia, and other psychiatric disturbances Memory loss Joint pains and muscle cramps Hair loss from an autoimmune process directed against the hair follicles Menstrual irregularities (typically menorrhagia, infertility, and loss of libido [emedicine.medscape.com]

• Amenorrhea

  Adolescents with overt hypothyroidism can also present with delayed or arrested pubertal development, irregular menstrual periods, menometrorrhagia, or amenorrhea in girls (41, 46). [frontiersin.org]

• Seizure

  These include: Infertility, miscarriage, and giving birth to an infant with birth defects High cholesterol Severe cases can result in heart failure, seizures, coma, and death. [medicalnewstoday.com]

  Myxedema Severe untreated hypothyroidism leads to myxedema, a condition characterized by the following: Heart failure Seizures Loss of consciousness Death. [innerbody.com]

  Symptoms can include strange behavior, confusion, muscle twitching, and seizures. [kidshealth.org]

  […] hypothyroidism from Hashimoto’s disease can cause other health problems, including: Infertility Miscarriage Giving birth to a baby with birth defects High cholesterol Very rarely, severe underactive thyroid, called myxedema, can lead to: Heart failure Seizures [womenshealth.gov]

Routine thyroid function tests and thyroid antibody tests are the blood tests used to diagnose Hashimoto’s thyroiditis. The thyroid peroxidase antibody test is more sensitive than the thyroglobulin antibody test and is the preferred test for confirming autoimmune thyroid disease. If a thyroid nodule is present, an ultrasound examination may be performed [8]. In patients with a dominant nodule, a fine-needle aspiration biopsy should be performed to exclude malignancy.

• Thyroid-Stimulating Hormone Decreased

  The diagnosis was based on clinical (i.e., weakness, somnolence, cold intolerance, dry skin, weight gain, constipation), laboratory (significant elevation of thyroid-stimulating hormone, decreased free thyroid hormones, positive anti-thyroid antibodies [nature.com]

• Thyroid-Stimulating Hormone Increased

  As the disease progresses, the TSH (thyroid stimulating hormone) increases since the pituitary is trying to induce the thyroid to make more hormone, the T4 (a different thyroid hormone) falls since the thyroid can't make it, and the patient becomes hypothyroid [endocrineweb.com]

• Lymphocytosis

  The TSH concentration was 3.66μIU/ml (normal: <4.2), and the blood count indicated lymphocytosis – monocytosis, with an erythrocyte sedimentation rate (ESR) of 6mm in the first hour. [elsevier.es]

• Lymphocytic Infiltrate

  However, the concurrent lymphocytic infiltration of the thyroid gland, as found in Hashimoto's thyroiditis, and of the ectopic thyroid tissue is extremely rare. [ncbi.nlm.nih.gov]

  Histopathological studies indicate the presence of diffuse lymphocyte infiltration by both B cells and cytotoxic T cells. [symptoma.com]

  Figure 1: Mild lymphocytic infiltrate in follicular cells cluster and increased background lymphocytes (Leishman's stain, ×400) Click here to view Group II ( n = 24) patients showed moderate lymphocytic infiltrate with evidence of follicular cell destruction [cytojournal.com]

In patients with Hashimoto’s thyroiditis, the goal of treatment is to maintain level of thyroid hormones throughout the life. This can be achieved by administering a proper dose of levothyroxine sodium orally. Dietary supplement of selenium along with levothyroxine sodium is also recommended by the FDA. Gluten-free diet is also proved to reduce the level of circulating anti-thyroid peroxidise and other thyroid-related serum antibodies [9].

Patients with hypothyroidism need lifelong thyroid hormone replacement. Euthyroid patients with Hashimoto’s thyroiditis may have an increased risk of developing hypothyroidism and rarly hyperthyroidism. Though unusual, patients with chronic thyroiditis may change from a hypothyroid to a euthyroid state or to a hyperthyroid state because of the development of stimulating thyroid stimulating hormone (TSH) receptor autoantibodies of Graves disease [6].
In a prospective study of 82 women with subclinical hypothyroidism followed over a mean of 9.2 years, risk factors for overt thyroid failure were identified based on initial evaluation. The incidence of overt hypothyroidism was increased in patients positive for thyroperoxidase antibodies (58.5% vs 23%) and impaired thyroid reserve (53% vs 38%), as determined by the degree increase in T3 levels after thyroid-releasing hormone (TRH) administration.

Inflammation of the thyroid gland due to this autoimmune disease leads to insufficient amount of thyroid hormones (T3 and T4) in the body which is responsible for metabolism [2]. Excess intake of iodine may impart toxicity to thyrocytes, induce thyroglobulin antigenicity and block the hormone synthesis by the thyroid gland.

Hashimoto’s thyroiditis can affect all age groups including children. It is approximately 7 times more common in women, with its peak onset usually between the ages of 30 to 50 years. On an average 1 in 1000 people are affected by this disease. It is prevalent in geographic areas where dietary iodine intake is high [3].

Though there are no sufficient studies reporting the mechanism of induction of the condition by excess iodine in the body, the same may be explained by the oxygen free radical release mechanism upon the enzymatic reaction of thyroid peroxidise and thereby increasing the immunogenicity of thyroglobulin [4].

In Hashimoto’s thyroiditis gradual destruction of follicles in the thyroid gland occurs when antibodies are produced against thyroglobulin and thyroid peroxidase. Activation of cytotoxic T-lymphocytes followed by cell-mediated immune response is the major cause for thyrocyte destruction. The thyroid gland becomes enlarged and lobulated. Antibodies such as TSH receptor-blocking antibodies, anti-thyroid peroxidise and antithyroglobulin can be found in the systemic circulation.

Glandular hyperplasia results due to the decreased ability of the thyroid gland to produce hormones. Also, the replacement of normal cells by fibrous and lymphoid tissue occurs. Histopathological studies indicate the presence of diffuse lymphocyte infiltration by both B cells and cytotoxic T cells [5]. In patients with Hashimoto’s thyroiditis, thyrocytes express the Fas gene, which causes thyroid apoptosis by interaction with the Fas ligand present on the surface of the thyrocyte.

It is not possible to prevent Hashimoto’s thyroiditis as it an autoimmune disease.

Hashimoto’s thyroiditis is named after the Japanese discoverer, Hakaru Hashimoto. It is the most common cause of primary hypothyroidism [1]. Family history of this autoimmune disease, selenium deficiency, stress and smoking are the major contributing factors for this disease. Hashimoto’s thyroiditis is initiated by environmental factors in genetically predisposed persons.

The thyroid gland is a butterfly-shaped organ that is found in the front part of your neck. Thyroid hormones regulate body temperature, heart rate, and weight gain or loss.

Definition

Hashimoto’s thyroiditis is an autoimmune thyroid disorder that occurs when the immune system attacks the thyroid gland. It can be seen in all age groups including children but more common in women of age group 30 to 50 years. Though it cannot be prevented, it can be managed well by maintaining thyroid hormone levels in your body.

Cause

Destruction of thyroid gland due to autoimmune response of the body is the major cause for Hashimoto’s thyroiditis, leading to inadequate level of thyroid hormones in your body. It is prevalent in geographic areas where dietary iodine intake is high.

Symptoms

Common symptoms of the disease are dry skin, weight gain, cold intolerance, voice hoarseness, pressure symptoms in the neck from thyroid enlargement, tiredness, weight gain and hair thinning. Other symptoms are depression, sleeplessness, memory loss, deafness, constipation, joint pain, muscle pain, slow heart beat and irregular periods in women.

Diagnosis

Thyroid hormone levels in the body are obtained by blood tests. An ultrasound uses sound waves to show pictures of your thyroid on a monitor. A thyroid scan shows how well your thyroid is working. You may be given a dye before the pictures are taken to help caregivers see the pictures better. Fine needle biopsy is a procedure where a small needle is used to take a sample of your thyroid gland for tests [10].

Treatment

Maintaining the normal thyroid hormone level in the body is the basis of treatment. In addition, gluten-free diet and intake of dietary selenium also help to reduce the level of circulating thyroid specific antibodies.

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