What is multinodular goitre?
Goitre is defined as an abnormal enlargement of the thyroid gland. Multinodular goitre is the presence of multiple nodules or bumps on an abnormally enlarged thyroid gland. These thyroid nodules are common, harmless, and mostly noncancerous. However, sometimes, these nodules can cause the thyroid gland to produce excessive thyroid hormone resulting in a condition called hyperthyroidism. Multinodular goitres like solitary thyroid nodule are also linked with small (less than 5%) risk of thyroid cancer.
The thyroid gland is a butterfly-shaped gland located in front of your neck just below the voice box (larynx). It is responsible for the production and secretion of thyroid hormones that help regulate your body’s metabolism such as heart rate, breathing, body temperature, weight, blood pressure, and several other bodily functions.
Causes and risk factors of multinodular goitre
The causes of multinodular goitres are mostly unknown. However, some of the conditions and risk factors that the medical community believe may cause multinodular goitres include:
- Hashimoto’s or Grave’s disease: Autoimmune conditions are associated with increased risk of thyroid nodules and thyroid conditions.
- Iodine deficiency
- Hereditary factors
- Gender: Females are 2 to 3 times more likely to develop thyroid nodules and thyroid disease than men.
- Advanced age: Older women are more likely to develop thyroid nodules.
- Family history of multinodular goitres.
Signs and symptoms of mmultinodular goitre
Multinodular goitres generally do not cause any symptoms; however, if the nodules enlarge in size and compress other structures in the neck, it may lead to:
- Pain at the base of the neck
- Breathing difficulties
- Swallowing difficulties
- Hoarseness in voice
- A feeling of food stuck in the throat
If the nodules produce excessive thyroid hormones, you may exhibit symptoms of hyperthyroidism such as:
- Sudden and unexplained weight loss
- Muscle weakness
- Increased appetite
- Trouble sleeping
- Rapid or irregular heartbeat
- Hand tremors
- Excessive sweating
In some instances, thyroid nodules occur in patients with Hashimoto’s disease, an autoimmune condition that escalates the chances of developing hypothyroidism, producing symptoms of hypothyroidism such as:
- Dry skin
- Hair loss
- Swelling in the face
- Intolerance to cold
- Unintentional weight gain
Diagnosis of multinodular goitre
Multinodular goitre is mostly detected during a routine physical examination of the neck where your doctor will check for enlarged thyroid gland, size and shape of the nodules. Once a nodule is discovered, the following tests may be ordered for further details:
- Thyroid function test: This test measures blood levels of the thyroid-stimulating hormone (TSH) and helps to determine whether your thyroid gland is functioning normally or not. The test helps to detect if you have hyperthyroidism (where your thyroid gland is producing too much thyroid hormone) or hypothyroidism (where your thyroid gland is not producing enough thyroid hormone).
- Ultrasound of the thyroid: This test uses sound waves to create images of your thyroid. The test utilises a lubricating gel and a device called a transducer to gently move over your neck to look at the size and texture of the thyroid gland. This test can indicate whether a nodule is a fluid-filled cyst or a solid mass of tissue.
- Fine-needle aspiration (FNA) biopsy: Your doctor will use a very thin needle to withdraw cells from the thyroid nodules which are examined under a microscope. This test helps to distinguish between noncancerous and cancerous thyroid nodules.
- Thyroid scan: A lab technician introduces a tiny quantity of radioactive iodine into your bloodstream with a syringe, and a special camera captures images of the thyroid gland to view nodules - this allows your doctor to check how well the thyroid gland is functioning. This test is unsafe for the health of expectant or breastfeeding women.
Treatment for multinodular goitre
The treatment depends upon the size and the type of the multinodular goitre and may involve the following methods:
- Watchful waiting: If a multinodular goitre is noncancerous and not causing any symptoms, wait and watch method is employed where the size of the goitre is evaluated systematically. This involves regular physical exams and thyroid function tests. You may also have a thyroid biopsy and ultrasound exam to look for any change in nodules.
- Medications: Anti-thyroid medications such as methimazole and propylithiouracil are some of the medication options that are employed for managing toxic multinodular goitre that trigger symptoms of hyperthyroidism. These medications work by gradually reducing the symptoms by preventing the production of excess thyroid hormones in your body by multinodular goitre.
- Surgery: You will need to have surgery to remove part or all of your thyroid gland if your goitre is cancerous or suspected to be cancerous, or compressing other structures in the neck causing “obstructive symptoms“ such as difficulty breathing or swallowing. This surgery is known as thyroidectomy and is performed under general anaesthetic as an inpatient procedure that allows you to go home the next day.