Goiter - Types, Causes, Symptoms, and Treatment

What Is a Goiter?

Goiter is a swelling or lump in the neck resulting from an enlarged thyroid gland. Typically, the thyroid gland is not visible, but in the case of goiter, the gland enlarges and forms a lump that can be easily seen. Over 90 percent of goiter cases globally are due to iodine deficiency. Most goiters are benign and rarely malignant.

What Are the Types of Goiter?

Goiters are mainly classified into two types:

1. Nodular Goiter: When solid or fluid-filled lumps develop within the thyroid gland, this condition is called nodular goiter. These nodules grow at different rates and secrete thyroid hormones. Inactive nodules may be malignant.

2. Diffuse Goiter: The whole thyroid gland swells and feels smooth due to hyperplasia in the case of diffuse goiter.

Goiters are also classified based on their size as:

1. Class I: Goiter cannot be typically seen and only be felt on palpation.

2. Class II: Goiter is palpable and also seen.

3. Class III: Goiter is massive, and palpation results in compression marks.

Based on their functionality goiters can be classified as:

1. Toxic Goiter: Goiter that is associated with overproduction of thyroid hormones and subsequent hyperthyroidism is known as toxic goiter. It may be diffused (in the case of Graves’ disease), nodular, or multinodular (in the case of Plummer disease).

2. Nontoxic Goiter: Goiter that does not cause overproduction or underproduction of the thyroid hormones, therefore it is not associated with either hyperthyroidism or hypothyroidism, is known as nontoxic goiter. It may be diffused or multinodular.

What Causes Goiter?

Globally, the most common cause of goiter is iodine deficiency. Before iodized salt was introduced in 1920, this deficiency was very prevalent. Selenium deficiency is also thought to be a contributing factor in goiter. In countries with iodized salt, autoimmune disorders like Grave’s disease and Hashimoto's thyroiditis are the leading cause. Mentioned below are the various causes of goiter:

• Iodine Deficiency: Iodine is necessary to produce thyroid hormones, and a lack of iodine in the diet can lead to an enlarged thyroid gland. But it is uncommon in countries where iodized salt is a part of the routine diet.

• Congenital Hypothyroidism: Inborn disorder of the thyroid gland to produce thyroid hormones often leads to goiter.

• Hashimoto’s Thyroiditis: Hashimoto's thyroiditis is an autoimmune disorder where the thyroid gland is gradually destroyed, leading to hypothyroidism and ultimately causing diffused or lobulated goiter.

• Pituitary Diseases: Diseases of the pituitary gland cause hypersecretion of the thyroid-stimulating hormone, which may lead to diffuse goiter.

• Grave’s Disease: Grave's disease is again an autoimmune disorder that causes increased secretion of the thyroid-stimulating hormone that makes the thyroid gland swell.

• Thyroid Nodule: Fluid-filled lumps, often called nodules, develop on both sides of the thyroid gland resulting in overall enlargement.

• Thyroid Cancer: Certain thyroid cancers can cause generalized swelling of the thyroid. These include infiltrating thyroid, papillary thyroid cancer, etc.

• Pregnancy: Human chorionic gonadotropin, a hormone produced during pregnancy, sometimes causes the thyroid gland to swell. However, this is a temporary condition that gets resolved postpartum.

• Thyroiditis: Inflammatory thyroid condition that causes swelling and pain in the thyroid. It leads to over or underproduction of thyroxine and ultimately swelling of the gland.

Apart from these factors, various other conditions like sarcoidosis, amyloidosis, acromegaly, cysts, etc., may also cause goiter.

What Are the Risk Factors of Goiter?

1. People over 40 years of age are at a higher risk of getting goiter.

2. Women are more susceptible to getting any type of thyroid disorder than men.

3. Pregnancy and menopause may also lead to thyroid imbalance and goiter.

4. Family history of autoimmune diseases.

5. Side effects of certain medications like Lithium and Amiodarone can also cause swelling in the thyroid gland.

6. Living in countries where iodine deficiency is expected in the diet.

7. Exposure to radiation like cancer treatment.

What Are the Symptoms of Goiter?

The primary symptom of goiter is swelling in the thyroid gland ranging from a small lump to multiple nodules. Apart from this, the following symptoms may also be seen:

1. A hoarse voice.

2. Feeling of fullness in the neck.

3. Feeling pressure on the food pipe and the windpipe.

4. Difficulty in swallowing.

5. Persistent cough.

6. Difficulty in breathing.

7. Swollen neck veins.

In Case of Active Goiter With Hyperthyroidism:

1. Persistent sweating.

2. Nausea and vomiting.

3. Diarrhea.

4. Unusual weight loss.

5. Increased heartbeat.

6. High blood pressure.

7. Muscle weakness.

8. Tremors in hands.

In Case of Active Goiter With Hypothyroidism:

1. Unusual weight gain.

2. Constipation.

3. Tiredness and lethargy.

4. Irregular period.

5. Depression.

6. Dryness of skin.

How Is Goiter Diagnosed?

Diagnosis of goiter is initially done with the help of clinical examination and studying various signs and symptoms in the patient, followed by these evaluations:

• Blood Tests: Blood examinations can show any variations in the levels of thyroid hormone that are causing goiter.

• Antibody Tests: An antibody test can reveal the presence of any abnormal antibodies in the blood that may lead to goiter.

• Imaging Tests: Image tests are done to evaluate the size of the goiter and the presence of any nodules.

• Biopsy: In the case of the presence of nodules, a fine needle biopsy is done to take samples of fluids or tissues. These samples are then tested for thyroid cancer.

• Thyroid Scan: A radioactive material is injected into the thyroid gland to produce an image of the thyroid on a computer screen. This test is done to check the functioning of the thyroid.

What Is the Treatment for Goiter?

Treatment of goiter may be simple or complex depending upon its type and stage. The condition does not require treatment if the swelling is minor and the thyroid hormone levels are balanced. However, in other cases, the following treatments are done:

1. Thyroid Hormone Replacement Drug: If the goiter is due to hypothyroidism, thyroid hormone replacement drugs are given to balance the deficiency of thyroid hormones in the body. Drugs like Synthroid may also slow down or lower the growth of the thyroid gland.

2. Antithyroid Drugs: If the goiter is due to hyperthyroidism, then antithyroid drugs are given to regulate the levels of thyroid hormones. Drugs like Tapazole and Propylthiouracil may be prescribed; these drugs prevent the production of T3 (triiodothyronine) and T4 (thyroxine) hormones. These drugs also stop the growth of the thyroid or even shrink it.

3. Radioactive Iodine Treatment: A dose of radioactive iodine is given to shrink the thyroid gland.

4. Thyroidectomy: It is the surgical removal of the thyroid gland. Thyroidectomy is done in cases where the goiter does not respond to thyroid replacement drug or antithyroid drug and continues to grow. In addition, it is also done in cases where the goiter is aesthetically undesirable and has thyroid cancer.

Conclusion:

Goiters are uncomfortable and, if noticeable then anesthetic to see, but they are rarely dangerous. However, it is the consequence of an underlying thyroid disorder that might require immediate treatment. Therefore, it is crucial to consult a doctor if you see a lump or swelling in front of your neck. Early diagnosis and prompt treatment can contain the disease and prevent any further complications.