Struma, also known as a goiter, is a symptom of a whole range of diseases. The causes are various, for example a lack of iodine in diet, inflammations or cancerous processes. Struma is often very visible, forming a swelling on the neck, but it can also be less obvious and only discernible by palpation or ultrasound. Struma is present in around 5% of population, but it can afflict up to 75% in areas with severe iodine deficiency.
A thyroid gland is an organ found on the front of the neck, dedicated to producing hormones triiodothyronine, thyroxine and calcitonin. The main purpose of the first two is increasing the production of proteins, breaking down fat and influencing oxygen usage. Calcitonin influences the amount of calcium by moving it from blood into bones. The thyroid gland needs a sufficient supply of iodine, which it absorbs from blood, to function properly. Lack of iodine can lead to a lack of hormones, which directly contain iodine, which causes specific symptoms. A fundamental purpose of these is also the development of brain both in children and in fetuses.
Development of struma
Worldwide, the most common cause of goiter is an insufficiency of iodine in diet. At a time when iodine was not added to kitchen salt, this problem was present in developed countries as well. Especially in mountainous regions, where people wouldn't consume enough fish, which are a natural source of iodine. These areas are referred to as endemic, meaning struma is present in more than 10% of all population.
In developed countries today, struma is usually cause by different reasons. One possibility is the Graves-Basedow disease, which is an autoimmune disease where the immune systems turns against the cells of the body, damaging certain organs. Other possible cause is a thyroid adenoma, a benign tumor, which manifests mainly by an increased hormonal production known as hyperthyroidism. A frequent cause of struma are inflammations, which appear in several forms. Issues with hormonal production can cause an increased pressure to produce hormones on the thyroid gland, causing its swelling.
Strumigens, compounds disturbing the process of hormonal production also contribute to the development of struma. They are found in certain food, such as cabbage, soy or broccoli. Smoking plays a considerable role as well.
Symptoms of struma
The main symptom of a struma is a swelling visible on the lower part of the neck, which can be observed by a naked eye, or by palpation or ultrasound. A small goiter, not tied with lowered (hypothyroidism) or increased (hyperthyroidism) hormonal production usually causes no issues and can often go unnoticed. If it gradually increases however, it can cause swallowing issues, pain, it can press down on the trachea, causing breathing problems. Voice chords and other throat structures can be affected as well.
Diagnosis of struma
Struma is diagnosed by look and palpation, which should find an observable swelling. Suspicions are verified by ultrasound, which will reveal the size of the struma and discover any potential changes in the tissue. Aside from the gland itself, we may also judge its surrounding area, such as lymphatic nodes. They swell due to inflammations or cancer. Another examination method is scintigraphy, which allows us to observe the gland's activity by supplying the body with a radioisotope ( radioiodine absorbed by the gland in this case) and observing its movement in the body. CT or magnetic resonance is used in deeper goiters, which endanger surrounding structures. These provide a 3D image of the examined area. If a cancerous process is suspected, a tissue sample is needed as well, which is taken by a special needle. A blood exam to discover an ongoing inflammation and sets the levels of thyroid hormones in blood is an integral part of examination and diagnostics.
Treatment of struma
The treatment of a struma is based on discovering the cause of the swelling of the thyroid gland. If the gland is working, producing normal levels of hormones, we usually just monitor the development, since the growth tends to to be very gradual in these cases, not damaging any surrounding structures. If the gland's production is lowered, hormones are supplied to the patients. On the other hand, if the gland produces more hormones, the main drugs used are thyreostatics, inhibiting the gland's function. Acute inflammations are most commonly treated by antibiotics, subacute ones are treated with anti-inflammatory medication and chronic inflammations cause by damage of the immune system by supplying hormones, since the gland is not producing, or only producing a limited amount. Tumors are treated based on their biological activity, whether they are malignant or benign. Most tumors are benign and are referred to as adenomas, which are initially treated with thyreostatics and followed by a surgical removal of the affected lobe of the gland.