Goiter is the enlargement of the thyroid gland and is not cancerous. A person with goiter can have normal levels of thyroid hormone (euthyroidism), excessive levels (hyperthyroidism) or levels that are too low (hypothyroidism).
The thyroid is a gland, shaped like a butterfly, located at the base of the neck, just below the Adam's apple. If the thyroid gland grows larger than normal the patient has a condition known as goiter. Goiters are generally painless; however, if the gland gets very large the patient may have problems swallowing properly, and may also develop a cough.
Classification / Types of Goitre
They can be classified in several ways by morphology, appearance, cause and other characteristics.
- Simple (struma diffuse)
- Multinodular (struma nodosa)
- Uninodular (struma uninodosa)
- Diffuse (Graves)
- Toxic multinodular
- Toxic nodule
- Various causes
- Chronic infection
Other type of classification
- Class I - palpation struma - in normal posture of the head, it cannot be seen; it is only found by palpation.
- Class II - the struma is palpative and can be easily seen.
- Class III - the struma is very large and is retrosternal; pressure results in compression marks.
Signs and symptoms of Goitre
Goiter associated with hypothyroidism or hyperthyroidism may present with symptoms of the underlying disorder although the symptoms are often unspecific and hard to diagnose.
Goiter not associated with hormonal abnormalities will not cause any symptoms aside from the presence of anterior neck mass. However, for particularly large masses, compression of the local structures may result in difficulty in breathing or swallowing. In those presenting with these symptoms, malignancy must be considered.
Toxic goiters will present with symptoms of thyrotoxicosis such as palpitations, hyperactivity, weight loss despite increased appetite, and heat intolerance.
Causes of Goitre
Worldwide, the most common cause for goiter is iodine deficiency. Selenium deficiency is also considered a contributing factor. In countries that use iodized salt, Hashimoto's thyroiditis is the most common cause. Further causes include
- thyroid autonomy
- autoimmune conditions of the thyroid (Hashimoto thyroiditis, Morbus Basedow)
- medications and substances such as lithium, antithyroid agents, thyocyanate
- inflammations (thyroiditis)
- benign and malignant neoplasms
- pituitary problems
- thyroid hormone insenstitvity
- sarcoidosis, amyloidosis
- hydatiform mole