What is Hashimoto's disease?

Your thyroid gland is a butterfly shaped organ located on the front of your neck. Its main function is to produce a thyroid hormone that helps regulate your metabolism. Hypothyroidism occurs when a person has a decrease in their thyroid function. Hashimoto thyroiditis, also known as Hashimoto’s disease, is the most common cause of hypothyroidism in the U.S.

Hashimoto’s disease causes chronic inflammation of the thyroid, as antibodies form attacking thyroid cells due to the changes to your immune mechanisms.

Risk factors

Stress, infections, certain medications, and environmental and genetic factors are all thought to be triggers of Hashimoto’s disease. Hashimoto’s disease also is thought to be more common in females compared to males and is mostly seen between the ages of 30 and 50, with incidence increasing as you age.

Symptoms of Hashimoto’s disease

In some cases, people may not notice the signs or symptoms of Hashimoto’s disease, as thyroid function can be normal. In some rare cases, thyroid function may be increased. However, in most cases, a decrease in thyroid hormone production results in chronic inflammation. This can cause these symptoms:

• Fatigue
• Weight gain
• Constipation
• Dry skin
• Hair loss
• Cold intolerance
• Depression
• Menstrual irregularity
• Joint pain and muscle cramps

Problems associated with Hashimoto’s disease

Enlargement of the thyroid gland, also known as a goiter, can occur in patients with Hashimoto’s disease. Most of the time, the goiter does not cause pain. Additionally, it’s not uncommon to see thyroid nodules or abnormal growth of thyroid cells forming lumps. When thyroid nodules or a goiter become big enough, other symptoms may occur, including:

• Swallowing difficulty
• Hoarseness
• Breathing problems

Why you should seek care

If you have any of the above symptoms, your doctor may recommend you undergo a thyroid function testing and, sometimes, ultrasound to evaluate your thyroid gland and nodule size. In some cases, a rapidly enlarging thyroid gland can be related to thyroid lymphoma, which is an uncommon, yet highly treatable, form of thyroid cancer. Hashimoto’s disease also can be associated with other autoimmune disorders, such as:

• Type 1 diabetes
• Vitiligo
• Gluten sensitivity
• Rheumatoid arthritis
• Addison’s disease or pernicious anemia

Diagnosis

Hashimoto’s disease generally is diagnosed using laboratory testing. Decreased thyroid function and increased thyroid antibody levels (thyroid peroxidase and thyroglobulin antibodies) usually are adequate to establish a diagnosis.

Treatment

Treatment for Hashimoto’s disease often consists of thyroid hormone replacement using a medication called levothyroxine. Levothyroxine generally is dosed based on your weight. It’s important to make sure you follow directions while using medication of this nature, as it is recommended levothyroxine be taken on an empty stomach 30 to 60 minutes before eating. After starting on medication, thyroid hormone testing needs to be repeated in six to eight weeks for dose adjustment, with the goal of returning your thyroid hormone level to a normal range.

Make sure to speak to your primary medical care provider if you have any questions. They can provide answers to help keep you and your thyroid healthy.

Sakine Sever, M.D., is an endocrinologist at Mayo Clinic Health System in Mankato.