What is Goitre?
An enlargement of the thyroid gland, a butterfly-shaped gland which is present at the front of the throat and below the Adam’s apple, is called goitre. The thyroid gland comprises of two lobes that lie on either side of the windpipe joined by a bridge of tissue called the isthmus. It is controlled by the pituitary gland, which prompts the thyroid to secrete the hormones thyroxine (T4) and tri-iodothyronine (T3) by releasing thyroid-stimulating hormone (TSH). Excessive stimulation of the thyroid gland by TSH can result in a goitre.
Location of Thyroid
Goitre in the neck region
What are the Types of Goitre?
Goitre is classified as diffuse or nodular.
- In diffuse goitre the whole thyroid gland swells and its smooth to touch
- In nodular goitre, solid or fluid-filled lumps called thyroid nodules develop in the thyroid gland. Nodular goitre is further classified into two types:
- Uninodular with only one nodule
- Multinodular with more than one nodule
The nodules may be inactive or toxic
Goitre may also be classified as endemic and sporadic.
- Endemic goitre, occurs due to insufficient dietary iodine intake. More than 10% of the community is usually affected.
- In sporadic goitre, a lesser number of individuals from the community are affected. The risk factors include a positive family history, dietary iodine deficiency, age (over 40 years) and female gender.
History
There have been references to goiter in historical Chinese texts as far back as 2700 BC. The high prevalence of the condition, with relatively little knowledge of its pathogenesis and of preventative techniques, led to its early recognition. Burnt sponges and seaweeds were used to treat the condition as far back as 1600 BC.
In 85 AD, a Chinese physician, Tshui Chin-thi, differentiated between fixed, malignant tumors and mobile, benign tumors in the neck.
In Indian Ayurvedic medicine, goiters were referred to as “galaganda”, and were classified into three categories to refer to hyperthyroidism, hypothyroidism and thyroidal cysts. A physician named Charaka noted that goiters could be prevented by the consumption of certain foods, such as milk, rice, barley and cucumber. In ancient Greek medicine, Hippocrates and Plato both made references to the thyroid gland, which they believed was responsible for lubricating the respiratory passageways.
Aetius mentioned the use of surgery to treat goiter in the 6th century, believing that it was a hernia of the larynx. In fact, the term “goiter” is likely to have originated from the Latin term guttur, meaning larynx of the bronchus. In the 7th century, Paulus Aegineta categorized goiter as either steatomatous or hyperplastic. In the 8th century it was associated with nervous symptoms, and in the 12th century the link with eye disease, increased appetite was noted. The first record of a successful thyroid surgery was in the 10th century, performed by Albucasis, who removed a large goiter from a man under opium sedation.
Robert Graves and Carl von Basedow are known for their accurate description of goiters and other abnormalities of the thyroid gland. This was the origin of the Merseburg Triad of exophthalmos, goiter and palpitations, described by von Basedow, in 1840.
In 1909, Emil Theodor Kocher won a Nobel Prize for his work in thyroidology, including his innovative techniques for thyroid surgery, and other endocrine conditions.
In this time period, thyroid extract was commonly used in medical practice, starting with Horsley and Murray. Thyroxine crystals were isolated in 1914 by Kendall. Sometime later, in 1952, triiodothyronine was discovered, which helped to advance the study of thyroidology significantly.
Epidemiology
Worldwide, the most common cause of goiter is iodine deficiency. It is estimated that goiters affect as many as 200 million of the 800 million people who have a diet deficient in iodine. In the Wickham study from the United Kingdom, 16% of the population had a goiter.
In a German study, 635 people underwent ultrasonographic thyroid screening, as well as basal TSH measurement, during a preventive-health checkup. Thyroid nodules were detected in 432 (68%) of the persons screened; in a previous German study, ultrasonographic screening of more than 90,000 people detected thyroid nodules in 33% of the normal population.
The incidence of thyroid cancer has been rising worldwide. The reasons are unclear, but this trend may be related to better detection and diagnostic methods.
Causes of Goitre
Causes of this swelling include:
- Underactive thyroid (hypothyroidism)
- Overactive thyroid (hyperthyroidism)
- Lack of iodine in your diet. Iodine is a mineral found in milk, fish and some plant foods and as an additive in table salt
- Pregnancy or menopause
- Some medication, including lithium
- Radiation exposure
- Thyroid cancer
- Women are more likely to develop goitres than men are, especially during pregnancy or menopause.
- The risk of having a goitre increases as people get older.
- A goitre may be due to swelling of the whole of the thyroid gland, called a diffuse goitre, or from individual lumps, called a nodular goitre.
- A diffuse goitre will feel smooth unlike the lumpier nodular goitre.
Other causes of goiter
Less common causes of goiter include the following:
- Nodules – benign lumps
- Smoking – thiocyanate in tobacco smoke interferes with iodine absorption
- Hormonal changes – pregnancy, puberty, and menopause can affect thyroid function
- Thyroiditis – inflammation caused by infection, for example
- Lithium – a psychiatric drug that can interfere with thyroid function
- Overconsumption of iodine – too much iodine can cause a goiter
- Radiation therapy – particularly to the neck
Risk Factors of Goitre
Goitres can happen to anyone at any given point in their life. A person may be at a higher risk of developing a goitre with the following conditions:
- Has a lack of iodine in your diet
- Is a female
- Is above the age of 40
- Has a family history of autoimmune disease
- Either pregnant or menopausal
- Either had radiation treatment near your neck or have been in any other way exposed to radiation in a nuclear facility or test
Signs and symptoms of goiter
Most goiters are asymptomatic (produce no symptoms). The following are the most common symptoms that are seen with goiter:
- Throat symptoms of tightness, cough, and hoarseness
- Trouble swallowing (dysphagia)
- In severe cases, difficulty breathing (possibly with a high-pitch sound)
Other symptoms may be present because of the underlying cause of the goiter, but they are not because of the goiter itself. For example, if the cause is hyperthyroidism, the overactive thyroid can cause symptoms such as:
- Nervousness
- Palpitations
- Hyperactivity
- Increased sweating
- Heat hypersensitivity
- Fatigue
- Increased appetite
- Hair loss
- Weight loss
In cases where goiter is a result of hypothyroidism, the underactive thyroid can cause symptoms such as:
- Cold intolerance
- Constipation
- Forgetfulness
- Personality changes
- Hair loss
- Weight gain
Aside from the swelling itself, many cases of goiter present no symptoms or signs at all.
Complications
- Small goiters that don’t cause physical or cosmetic problems aren’t a concern. But large goiters can make it hard to breathe or swallow and can cause a cough and hoarseness.
- Goiters that result from other conditions, such as hypothyroidism or hyperthyroidism, can be associated with a number of symptoms, ranging from fatigue and weight gain to unintended weight loss, irritability and trouble sleeping.
Assessing the situation
When you have a goitre, a doctor will usually do some blood tests to check if you are making too much or too little thyroxine or T3. Blood tests may also help to find out the cause of some goitres. Other tests may be done to find out the cause of the goitre. For example:
- An ultrasound scan of the thyroid. This is the best test for thyroid swellings. An ultrasound scan is a safe and painless test which uses sound waves to create images of organs and structures inside your body. It can tell if a nodule is a cyst or a solid lump.
- A small piece of tissue (a biopsy) may be taken from a nodule to look at under the microscope. The biopsy is done by inserting a thin needle into the nodule. It is a simple and safe procedure. The specialist doing the biopsy can see where they are inserting the needle by doing an ultrasound scan at the same time.
- Occasionally other specialist blood tests are needed to help establish the cause. Occasionally a CT scan or an MRI scan is needed.
How do you Treat Goitre?
Treatment of goitre depends on the underlying cause:
- Goitre caused due to hyperthyroidism is treated with drugs that slow down the activity of the thyroid gland. Treatment with radioactive iodine destroys some or all of the thyroid’s hormone-producing cells. If these treatments fail to cure the thyroid disease, then the thyroid gland is surgically removed.
- Goitre caused due to hypothyroidism is treated with lifelong thyroid hormone replacement therapy.
- Goitre due to iodine deficiency is treated with iodine-rich foods, such as seafood and iodized salt.
- Benign thyroid nodules are reduced in size with the help of medications, destroyed with radioactive iodine treatment or removed using surgical methods.
- Thyroid cancer is removed surgically which is then followed by radioactive iodine treatment.
Thyroidectomy refers to the surgical removal of the thyroid. Thyroidectomy relieves the compression of the nearby structures because of the enlarged gland, thereby improving symptoms relating to difficulty in swallowing, cough or shortness of breath. The different types of thyroidectomy are illustrated below:
- Total thyroidectomy involves the surgical removal of the whole gland.
- Near-total thyroidectomy involves the surgical removal of both the lobes except for a small amount of thyroid tissue.
- Subtotal thyroidectomy leaves 3 – 5 g of the tissue on the less affected side of the gland.
A possible after effect of thyroidectomy is recurrent nerve palsy as this nerve could be traumatized during surgery. Complications to the voice, swallowing or both can occur. If the four parathyroid glands which are located close to the thyroid are accidentally removed or injured, the patient’s blood calcium levels may drop resulting in tingling, muscle cramps and numbness. A severely low calcium level leads to throat spasm or a seizure.
Endoscopic techniques used to surgically remove the thyroid gland are minimally invasive and the scars are totally invisible. The safety of the operation lies on the quality of the images captured on the endoscopic high-definition camera.
How Do You Prevent Goitre?
Following are some tips to prevent goitre:
- Add only iodized salt to your food
- Eat seafood rich in iodine, such as sea weed, shrimps and shell fish.
- Avoid over exposure to radiation, be it at work place or during any kind of radiation treatment.
- Health Tips
Here are some common home remedies for treating and preventing goitre.
- Simple exercises, such as neck stretches or other similar exercises for the thyroid gland should be performed on a daily basis. Many fitness freaks suggest aerobic exercises along with jogging for all thyroid problems.
- Food items that can be included to treat goitre include oats, seafood, tomatoes, carrots, lettuce, garlic, strawberries, eggs (yolk), onions, citric fruits, pineapples, bananas, vitamin A rich foods, meat, dairy products, pulses, watermelons, grapes and dates.
