Hashimoto's Thyroiditis

Hashimoto's thyroiditis, also known as chronic lymphocytic thyroiditis, is an autoimmune disease that affects the thyroid gland. This condition is characterized by the destruction of the thyroid gland, leading to hypothyroidism. In this blog, we will discuss the definition, causes, types, signs and symptoms, diagnostic criteria, investigation, and treatment of Hashimoto's thyroiditis.

Definition:

Hashimoto's thyroiditis is an autoimmune disease that causes chronic inflammation of the thyroid gland, leading to a decrease in thyroid hormone production. This condition is the most common cause of hypothyroidism in the United States.

Causes:

The exact cause of Hashimoto's thyroiditis is unknown, but it is believed to be caused by a combination of genetic and environmental factors. Some of the risk factors associated with Hashimoto's thyroiditis include:

Family history of autoimmune disease

Female gender

Exposure to radiation

Presence of other autoimmune diseases

Nutrient deficiencies, particularly iodine and selenium

Types:

There are two types of Hashimoto's thyroiditis:

Silent thyroiditis: This type of Hashimoto's thyroiditis is characterized by a transient hyperthyroidism followed by a period of hypothyroidism. It is also known as painless thyroiditis because patients do not experience any pain or discomfort.

Postpartum thyroiditis: This type of Hashimoto's thyroiditis occurs in women after giving birth. It is characterized by a transient hyperthyroidism followed by a period of hypothyroidism. In some cases, the thyroid function may return to normal, but in others, it may progress to permanent hypothyroidism.

Signs and Symptoms:

The signs and symptoms of Hashimoto's thyroiditis are similar to those of hypothyroidism and may include:

Fatigue

Weight gain

Cold intolerance

Dry skin

Constipation

Hair loss

Joint pain

Muscle weakness

Menstrual irregularities

Diagnostic Criteria:

The diagnosis of Hashimoto's thyroiditis is based on a combination of clinical and laboratory findings. The following tests may be ordered to confirm the diagnosis:

Thyroid function tests: These tests measure the levels of thyroid hormones (T3, T4) and thyroid-stimulating hormone (TSH) in the blood.

Thyroid autoantibody tests: These tests measure the levels of thyroid peroxidase antibodies (TPOAb) and thyroglobulin antibodies (TgAb) in the blood.

Ultrasound: This test is used to visualize the thyroid gland and evaluate the presence of nodules or inflammation.

Investigation:

If Hashimoto's thyroiditis is suspected, the following investigations may be ordered:

Thyroid function tests

Thyroid autoantibody tests

Ultrasound

Biopsy: A small sample of thyroid tissue may be removed for examination under a microscope to confirm the diagnosis.

Treatment:

The treatment of Hashimoto's thyroiditis is aimed at restoring normal thyroid function and managing the symptoms of hypothyroidism. The following treatments may be recommended:

Levothyroxine: This medication is used to replace the missing thyroid hormone and restore normal thyroid function.

Nutritional supplements: Iodine and selenium supplements may be recommended to address any nutrient deficiencies.

Lifestyle modifications: Eating a healthy diet, exercising regularly, and managing stress may help improve thyroid function and reduce the severity of symptoms.

Monitoring: Regular monitoring of thyroid function and autoantibody levels is necessary to evaluate the effectiveness of treatment and adjust the medication dose as needed.

The American Thyroid Association (ATA) has published guidelines for the management of Hashimoto's thyroiditis. These guidelines are based on the best available evidence and expert opinion and are intended to help healthcare providers diagnose and treat patients with Hashimoto's thyroiditis.

The ATA recommendations for the management of Hashimoto's thyroiditis include:

Diagnosis: Hashimoto's thyroiditis should be diagnosed based on clinical features, laboratory tests, and imaging studies.

Treatment: Levothyroxine therapy is recommended for patients with symptomatic hypothyroidism and for those with subclinical hypothyroidism who have positive thyroid peroxidase antibodies (TPOAb) and/or thyroglobulin antibodies (TgAb) and who are at risk for progression to overt hypothyroidism.

Monitoring: Patients with Hashimoto's thyroiditis who are receiving levothyroxine therapy should have periodic monitoring of serum TSH and free T4 levels. Annual monitoring of TPOAb and/or TgAb levels may also be considered.

Thyroid nodules: Patients with Hashimoto's thyroiditis who have thyroid nodules should be evaluated with ultrasound and fine-needle aspiration biopsy as indicated.

Pregnancy: Pregnant women with Hashimoto's thyroiditis should be monitored for thyroid function and treated with levothyroxine as needed to maintain normal thyroid function.

Cardiovascular disease: Patients with Hashimoto's thyroiditis should be screened for cardiovascular risk factors and treated as appropriate.

Lifestyle modifications: Patients with Hashimoto's thyroiditis should be counseled on the importance of maintaining a healthy lifestyle, including regular exercise, a healthy diet, and avoiding smoking and excessive alcohol consumption.

It is important to note that these recommendations are intended as guidelines and may not apply to every patient. Healthcare providers should use their clinical judgment and individualize treatment plans for each patient based on their unique circumstances.

In conclusion, Hashimoto's thyroiditis is a common autoimmune disorder that affects the thyroid gland. It can cause a range of symptoms, including fatigue, weight gain, and difficulty swallowing or breathing. If you are experiencing symptoms of Hashimoto's thyroiditis, it is important to see a doctor for an accurate diagnosis and appropriate treatment.

 

Dr.Muhammad Arsalan Khan
Diabetes Specialist
MBBS, MSc (Diabetes & Endocrinology)
CCD-BMJ-AKU-RCP (London)