· Goitre is an enlarged thyroid gland that causes the neck to swell. Goitre can mean that all the thyroid gland is swollen or enlarged or one or more swellings or lump develop in parts of the thyroid.
· The thyroid gland comprises of two lobes that lie on either side of the windpipe joined by a bridge of tissue called isthmus. It is controlled by the pituitary gland, which prompts the thyroid to secrete the hormones thyroxine (T4) and tri-iodothyronine (T3) by releasing TSH. Excessive stimulation of the thyroid gland by TSH can result in goitre.
· The thyroid gland makes thyroid hormone called thyroxine (T4) and tri-iodothyronine (T3). These hormones carried around the body in the bloodstream. Thyroxine and T3 help to keep the body’s function. Issues many cells and tissues in the body need thyroxine and T3 to keep them working correctly.
· The size of the goitre can vary from person to person. The normal human thyroid gland 10-20 gms and some goitrous thyroid gland weigh as much as 1,000 gms.
The thyroid gland is in the lower part of the front of the neck. It lies just in front of the windpipe (trachea). It has a right and left lobe which are connected together by a narrow band of thyroid tissue. It is roughly the shape of butterfly. If the thyroid enlarges, it causes a swelling in the neck which is goitre.
Types of Goitre:
Goitre is classified into two types:
1) Diffuse goitre:
In diffuse goitre the whole thyroid gland swells and it’s smooth to touch.
2) Nodular goitre:
These are the solid or fluid filled lumps called thyroid nodule develop in the thyroid gland. They make the thyroid gland feel lumpy to touch. Nodular goitre is further classified into two types:
a. Uninodular: They have one nodule
b. Multinodular: These have more than one nodule. The nodules may be inactive or toxic.
Goitre may also be classified as Endemic and Sporadic.
It occurs due to insufficient dietary iodine intake. More than 10% of the community is usually affected by the endemic goitre. When iodine intake is low, thyroid hormone production is low and in response the pituitary gland secretes greater quantities of the hormone thyrotropin (TSH) is an attempt to restore thyroid hormone production to normal. This excess thyrotropin stimulates not only thyroid hormone but also thyroid growth. Endemic goitre is more common among girls than boys. It occurs most frequently in inland or mountaneous region where the natural iodine content of the water and soil is very low. It can be easily prevented by use of salt or food to which iodine has been added. In young people increasing iodine intake results in regression of the goitre, however the likelihood of the expression diminishes with age. Surgical removal of the thyroid gland may be necessary if the goitre causes breathing or swallowing problems.
It occurs in lesser number of individuals from the community. The risk factor includes a positive family history, dietary iodine deficiency, age (over 40 years) and female gender.
Causes of Goitre:
· Insufficient iodine in the diet due to inadequate iodine intake of iodine rich foods or high consumption of certain foods that neutralize iodine, namely cabbage, broccoli and cauliflower, soy also induces goitre.
· Thyroid cancer such as infilterating papillary thyroid cancer, lymphoma and anoplastic thyroid cancer. This is a rare type of cancer in UK.
· Thyroid nodules or cysts within the thyroid, most are benign but should be assessed.
· Hyperthyroidism or hypothyroidism due to several causes.
· Thyroiditis like auto- immune thyroiditis (Hashimoto thyroiditis) and painless (post partum) thyroiditis,, it refers to inflammation of the thyroid gland.
· Having radiation treatment to neck and chest areas such as radiotherapy for neck cancer.
Symptoms and Signs of Goitre:
· A tight feeling in throat
· Difficulty in swallowing due to large goitre that presses the oesophagous or food pipe and windpipe (trachea).
· Hoarseness of voice.
· Difficulty in breathing, there may be a high- pitched sound when you breathe (stridor).
Diagnosis of Goitre:
· Physical examination is performed by doctor who examine for signs related to thyroid enlargement such as the size of the gland or nodule its firmness, mobility and tenderness.
· Blood tests are performed to check for thyroid hormone levels and specific antibody.The patient is identified to have an underactive thyroid of the TSH is elevated. Some patients with goitre may have normal thyroid hormone level.
· If the thyroid nodule is larger than 1.0-1.5 cm in diameter and with TSH levels of normal or high then the patient is advised a fine needle aspiration biopsy. The biopsy may reveal a benign nodule, thyroid cancer or an uncertain diagnosis.
· Ultrasound scan or radioactive iodine scan is performed. A thyroid sonogram or ultrasound sends inaudible sounds waves into the neck in such a way that the returning echoes determine the structure of thyroid and surrounding tissues. A radioactive scan determines if the nodule is hot nodule (that take up radioactive iodine) or a cold nodule (that take up less radioactive iodine). Cancerous nodule appears as cold nodule on a radioactive thyroid scan, though some benign nodule may also appear cold.
Treatment of Goitre:
1) Goitre is caused due to hyperthyroidism is rated with drugs that slow down the activity of thyroid gland. Treatment with radioactive iodine destroys some or the thyroid’s entire hormone producing cells. If this treatment fails to cure the thyroid disease, then the thyroid gland is surgically removed.
2) Goitre caused due to hypothyroidism is treated with lifelong thyroid hormone replacement therapy.
3) Goitre due to iodine deficiency is treated with iodine rich foods such as sea food or iodized salt.
4) Benign thyroid nodules are reduced in size with the help of medications destroyed with radioactive iodine treatment or removed during surgical methods.
5) Thyroid cancer is removed surgically which is then followed by radioactive iodine treatment.
6) Total thyroidectomy involves the surgical removal of whole gland. 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.
Prevention of Goitre:
1) Add only iodized salt in food.
2) Eat seafood rich in iodine such as sea weed, shrimps and shell fish.
3) Avoid over exposure to radiation, be it at work place or during any kind of radiation treatment.
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