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Goiter

Brief overview

  • Description:Enlargement of the thyroid gland, which can be visible or palpable, but does not have to be (colloquial: goiter)
  • Causes: Iodine deficiency, thyroid inflammation - partly autoimmune (e.g. Graves' disease, Hashimoto's thyroiditis), benign and malignant tumors of the thyroid gland, involvement of the thyroid gland by other malignant tumors, thyroid autonomy, certain substances in food and drugs, etc.
  • Symptoms: sometimes no, sometimes visible / palpable enlargement of the thyroid gland, feeling of lump, tightness or pressure in the throat, forced throat clearing or swallowing disorders
  • Diagnosis: Palpation examination, ultrasound, measurement of hormone levels in the blood, if necessary tissue removal
  • Treatment: medicinal, surgical or nuclear medicine (radioiodine therapy)
  • Prevention: Targeted iodine intake in certain life situations (pregnancy, growth phases, breastfeeding), generally iodine-rich diet

Goiter: description

A goiter, usually called goiter in common parlance, is one Enlargement of the thyroid gland. This can be so discreet that you can neither see nor touch it with the naked eye. But there are also cases in which the thyroid gland becomes the size of a football.

The thyroid gland is an important one Endocrine gland of the body, which sits just below the larynx. It produces the two hormones T3 (triiodothyronine) and T4 (thyroxine), which are important for the entire metabolism and circulation. In addition, the hormone calcitonin, which is involved in regulating the calcium balance.

Sizing the goiter

With the help of scales, the enlargement of the thyroid gland can be classified according to its extent. The World Health Organization (WHO) uses the following scale for the goiter size:

  • Grade 0: Goiter can only be detected by ultrasound
  • Grade 1: palpable magnification
  • Grade 1a: palpable enlargement, which is not visible even when the head is tilted backwards
  • Grade 1b: palpable enlargement visible when the head is tilted backwards
  • Grade 2: palpable and visible enlargement even with normal head posture
  • Grade 3: very large goiter with local complications (e.g. obstruction of breathing)

Goiter: causes and possible diseases

In Germany, goiter usually develops due to iodine deficiency. Other possible causes are, for example, inflammation or an underactive thyroid, malignant tumors or certain drugs.

Goiter due to iodine deficiency

The thyroid gland needs iodine to make the hormones T3 and T4. The trace element must be regularly taken in with food. In so-called iodine deficiency areas, including Germany, soils and water hardly contain any iodine. Food produced here is therefore poor in the trace element. Those who do not compensate for this in their diet, for example by using iodized table salt, can develop iodine deficiency goiter:

If the iodine deficiency persists, the thyroid produces too little T3 and T4. The drop in thyroid hormone levels in the blood "alarms" the pituitary gland, which then increasingly releases the hormone TSH (thyroid-stimulating hormone). It signals the thyroid to increase hormone production. The thyroid tries to achieve this by enlarging cells. In addition, new blood vessels and connective tissue are formed. In total, a goiter develops - as an attempt to compensate for the prevailing iodine deficiency and thus the deficient hormone production.

Goiter due to inflammation of the thyroid gland

Inflammation of the thyroid gland (thyroiditis) can also lead to goiter. In this case, the cells of the endocrine gland do not multiply or enlarge, but the tissue swells due to inflammation. Possible causes are, for example, infections with bacteria or viruses, injuries to the thyroid gland or radiation therapy in the neck region.

However, inflammation of the thyroid gland can develop with certain medications or after childbirth. In such cases, incorrect reactions of the immune system (autoimmune reactions) are considered to be the trigger for the inflammatory processes. Even with chronic forms of thyroiditis - Hashimoto's thyroiditis and Graves' disease - autoimmune thyroid inflammation occurs:

In case of Hashimoto's thyroiditis the immune system increasingly destroys the thyroid tissue. Ultimately, this always leads to a reduction in size and underactive thyroid, but a temporary goiter can also occur at the beginning of the disease.

At Graves diseaseantibodies are formed that attach to certain thyroid receptors that are actually responsible for recognizing TSH. These misdirected antibodies have the same effect as TSH and thus stimulate the thyroid gland to produce excessive amounts of T3 and T4 and to increase growth - a goiter forms.

Goiter due to tumors

Benign and malignant thyroid tumors can cause goiter through the uncontrolled proliferation of degenerate cells. In addition, metastases from other primary tumors can establish themselves in the thyroid gland and thus lead to an enlargement. In some cases the cause of a goiter is also a tumor in the pituitary gland, which leads to an increased production of TSH and thus indirectly causes a goiter.

Goiter from drugs and other substances

Certain drugs can also trigger goiter formation. These include, for example, antidepressants with the active ingredient lithium and anti-thyroid drugs (anti-thyroid drugs).

Certain substances in food (such as thiocyanate) can also trigger goitre.

Other causes

Sometimes goiter is the result of what is known as thyroid autonomy. In this case, the thyroid produces hormones in an uncontrolled manner.

Peripheral hormone resistance is rarely the cause of goiter. Here the thyroid hormones T3 and T4 cannot develop their effect in the target cells of the body tissue. More TSH is subsequently formed via a control loop because the body tries to correct the problem by increasing the production of thyroid hormones. The increased TSH levels cause goiter.

Other causes of a crump are, for example, altered thyroid enzymes, cysts in the thyroid gland, bleeding after an injury to the thyroid gland and hormone changes during pregnancy, puberty or menopause.

Diseases with this symptom

Find out here about the diseases that can cause the symptom:

Forms of goiter

A goiter can be classified not only according to its size, but also according to other criteria:

  • according to the anatomical position: A goiter can occur either in the normal position, i.e. in the neck area up to the breastbone (eutopic goiter) or grow on the base of the tongue until they reach behind the breastbone or the windpipe (dystopic goiter).
  • according to the nature:A Diffuse goiter is an evenly enlarged thyroid, the tissue of which appears homogeneous. At a Goiter nodosa on the other hand, the thyroid has a (Goiter uninodosa) or more (Multinodular goiter) Knot. Such nodes can potentially produce thyroid hormones even independently of the regulation via TSH (autonomous nodes). One then speaks of warm or hot knots. Cold nodes, on the other hand, do not produce hormones.
  • according to their function: A distinction is made between euthyroid, hyperthyroid and hypothyroid goiter. The euthyroid goiter produces normal levels of thyroid hormones, no more or less than a normal sized healthy thyroid. In the hyperthyroid goiter However, there is too high a concentration of T3 / T4 in the blood in one hypothyroid goiter on the other hand too little. From the size of a thyroid gland, therefore, one cannot generally infer its hormone production. A very large goiter can produce little T3 / T4 and vice versa.

If malignant changes occur in an enlarged thyroid, it is also referred to as goiter maligna. The bland goiter, on the other hand, is inconspicuous in terms of tissue structure and hormone production (neither malignant nor inflammatory, normal thyroid function).

Goiter: symptoms

The person concerned often does not notice a small goiter at all, it neither hurts nor restricts the patient, nor is it visible or palpable. If the goiter grows, however, this can cause local complaints, for example a feeling of pressure or tightness in the throat area or forced throat clearing. When the enlarged thyroid gland presses on the esophagus, difficulty swallowing can occur. If it compresses the windpipe, it can cause breathing difficulties. Breathing and the cardiovascular system can be affected if the goiter grows behind the breastbone (retrosternal goiter).

Goiter: When do you need to see a doctor?

Nowadays, goiter is usually an incidental finding as part of a routine examination. Only rarely do patients come to the doctor's office with an ever-increasing goiter. Anyone who notices a change in the size of the thyroid gland should definitely consult a doctor. He can rule out serious illnesses with the help of suitable examination methods or initiate the right therapy and resolve symptoms such as swallowing difficulties and breathing problems.

Goiter: diagnosis and therapy

First, the doctor will do various tests to determine if it is actually a goiter and what caused it. Then he initiates appropriate therapy.

diagnosis

An enlarged goiter can often be seen with the naked eye, a slightly enlarged thyroid can sometimes be felt on the neck. However, one is much more precise Ultrasound examination (Sonography) of the thyroid gland - it is therefore also the method of choice when diagnosing a goiter. The exact size of the thyroid can be determined using ultrasound. In addition, the doctor can often already tell whether it is a nodular or diffuse goiter.

The TSH levels in the blood provides information about the hormone status of the thyroid gland. It is increased, for example, when the production of thyroid hormones is reduced as a result of an iodine-deficient goiter. TSH levels are greatly increased when a tumor in the pituitary gland is the cause of the goiter.

In addition to this basic diagnosis, there are further investigation methodsto identify the goiter:

  • Measurement of free T3 and T4 or calcitonin in the blood
  • Thyroid scintigraphy: This nuclear medical examination makes it possible to distinguish cold nodules from warm / hot nodules in the case of a nodular goiter. This is important because cold lumps can also be thyroid cancer.
  • Tissue removal using a hollow needle (fine needle biopsy): It is usually carried out when a malignant tissue change in the thyroid is suspected. A small piece of tissue is removed from the suspicious area and examined under the microscope. This way, changed cells can be detected.
  • Chest X-ray (Rhƶntgen-Thorax): This allows the exact position of a goiter to be determined.

Once the cause and hormonal status of the enlarged thyroid are known, the doctor will initiate appropriate therapy.

therapy

At a Goiter due to iodine deficiency In principle, there are three possible therapy options: drug, surgical and nuclear medicine treatment.

Medical therapy

In the case of euthyroid goiter, iodide is first given in tablet form in order to provide the thyroid with enough iodine again. In this way, their volume can often be reduced by 30 to 40 percent. If the iodine treatment alone does not bring satisfactory results after six to twelve months, the administration of L-thyroxine (a form of T4) is also started. Above all, this lowers the TSH level and helps reduce goiter.

In the case of hyperthyroid goiter (with increased T3 and T4 production) or autonomic nodes, iodine substitution is out of the question, as this can lead to a hyperthyroid crisis. This is an acute, life-threatening metabolic imbalance caused by the sudden release of thyroid hormones. Especially in older patients, the level of hormone production in a goiter must be precisely determined, as autonomous nodes are often present here.

surgery

If a goiter has existed for a long time, it can often no longer be treated with medication. Then the doctor usually suggests an operation. This generally only removes part of the thyroid gland. If possible, a sufficiently large and functionally intact piece of the gland should remain in order to avoid lifelong hormone therapy. Sometimes the thyroid is removed entirely; the patient concerned then has to take thyroid hormones for life.

If a malignant tumor is the cause of a goiter, the entire thyroid must be removed. Those affected then have to take the vital hormones T3 and T4 for a lifetime.

Radioiodine therapy

Nuclear medicine radioiodine therapy is an alternative if, for example, there is an increased risk of surgery or if the goiter recurs after drug treatment. In this method of treatment, the patient is given a radioactive isotope of iodine that accumulates in the thyroid gland. There it partially damages the tissue and thus reduces the volume of the thyroid gland by up to 50 percent.

Other forms of goiter are treated on a cause-related basis:

In Graves' disease, in the initial phase of the autoimmune disease, the thyroid gland is usually enlarged and overactive, which is why so-called anti-thyroid drugs are used first. These are drugs that stop the production of thyroid hormones. As the final therapy, radioiodine therapy is usually used, and part of the thyroid gland may also be removed.

Hashimoto's thyroiditis is treatable, but currently not curable. As soon as a relevant part of the tissue of the endocrine gland is destroyed, the patient receives the missing thyroid hormones as medication.

Malignant thyroid tumors require complete removal (resection); radioiodine therapy may also be used for benign tumors.

In the case of peripheral hormone resistance, high doses of L-thyroxine may have to be treated.

Struma: You can do that yourself

Everyone can help ensure that a possible goiter is detected early or does not even develop in the first place:

Have regular checkups: Older people in particular should have their doctor checked regularly in order to find out about the start of a goiter as early as possible. Anyone who suddenly has difficulty swallowing or a lumpy feeling in the throat should also see a family doctor.

Keep an eye on iodine requirements: There are situations in life in which there is an increased need for iodine. Above all, this includes pregnancy, because the growing child must also be cared for. But iodine requirements are also increased when children are breastfeeding or when they are growing. Here you should pay particular attention to an adequate supply of the trace element - through a diet rich in iodine (see below) and, if necessary, through iodine tablets. The latter are particularly advisable during pregnancy because the iodine in the diet is insufficient to meet the needs. An iodine deficiency during pregnancy can have serious consequences for the unborn child, impair the physical development and maturation of the brain - this would then be a bigger problem than goiter.

Pay attention to the diet: A diet rich in iodine is recommended for the prevention and treatment of iodine deficiency goiter. But: Most plant-based foods as well as meat and dairy products from iodine deficient areas (such as Germany) hardly contain iodine. Therefore, foods are often fortified with iodine. In addition, experts recommend the use of iodized salt (iodized table salt).

By the way: marine animals have a relatively high proportion of iodine. Eating saithe, herring, or mackerel can therefore help one Goiter to prevent.

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