What is graves disease?
Graves disease is an autoimmune disease, in which hyperthyroidism occurs.
This is traditionally associated with swelling of the thyroid gland (goiter), bulging eyes (exoftalmus) and to a rapid heart rate (tachycardia). The combination is called the Merseburger trias. The simultaneous occurrence of all three of these symptoms, however, is comparatively rare. Typically is one of the symptoms in the foreground.
Origin of the disease
Due to an unknown cause, makes the body in patients with Graves disease, antibodies that work on a particular part of the thyroid gland. These antibodies (TSI) stimulate the TSH receptor on the thyroid receptors that are normally activated when the body has too little thyroid hormone. Because these antibodies now stimulate the TSH receptors of the thyroid gland is continuously turned on to the making of thyroid hormone, even though this is for a normal functioning of the body is not necessary.
Thyroid hormone is a hormone that controls processes in the body that have to do with obtaining energy (for example, sports, or stress). Because there are now too many is created of this hormone, resulting in a so-called hyperthyroidism, the patient has, inter alia, the feeling to be very hunted, much to sweat and to have palpitations. Another phenomenon that the patient often has pointed out, is a swelling of the thyroid gland, which in the middle to sense the front of the neck is, this is called goiter.
Graves disease symptoms
The thyroid hormones, thyroxine and tri-jew thyronine regulate the intensity of the metabolism. Too much thyroid hormone metabolism will be stimulated, which is reflected in the following complaints:
- Heat intolerance
- Weight loss (despite normal food intake)
- Insomnia
- Irritable mood
- Fear
- Excessive perspiration
- Hunted feeling, restlessness
- Tachycardia (rapid heartbeat sometimes more than 100 beats per minute)
- Tremor (trembling usually the fingers, hands)
- Disordered menstrual cycle
- Cardiac arrhythmias - very rarely
- Increased food intake
- Fatigue
- Muscle weakness
- Nausea and vomiting - rarely
- Eye problems (strabismus, change of vision, bulging eyes)
- Brittle hair
Diagnostics
Because it's too much of thyroid hormone (hyperthyroidism), may have multiple causes, there should be some studies be done to a good diagnosis. First of all, will at the suspicion of hyperthyroidism, blood tests are done to see if there is actually high values of thyroid hormones in the blood can be seen. There is at this blood test usually looked to two hormones:
TSH (thyroid-stimulating hormone)
TSH is a hormone that is produced by an area central to the brain that the pituitary gland is called. When too little thyroid hormone in the blood (FT4) is present, it is detected by the pituitary and TSH is created. This TSH will then bind to the TSH receptor of the thyroid gland and it is going to make more thyroid hormone.
Because in the case of Graves disease is present in the blood too many FT4 will detect this the pituitary gland. As a result, the pituitary gland stops making TSH. The doctors see in the results of the blood test so a very low TSH.
FT4 (Free Thyroxine 4)
FT4 is released into the blood common variant of one of the T4 thyroid hormone. This hormone is also bound to other molecules in the blood is called for and then just T4, here is not only looked at in the blood test. FT4 is a hormone that after conversion in certain cells in the body ensures greater energy production. This may be necessary when the body has to work hard, for example, during exercise, stress or other strenuous moments. But even if the body is at rest, it has a certain amount of thyroid hormone is needed.
At Graves disease are the aforementioned TSH receptors if it were attacked by the antibodies of the body. The active becoming TSH receptors provide an activation of the thyroid gland causing it to produce a lot of thyroid hormone. In the blood is therefore so far too large amount of FT4 seen.
On physical examination can in some cases be seen swelling under the skin of tibiae (peridermaal myxoedeem), the aforementioned goiter, and the coming forward of the eyes (exophthalmos). However, this clinical signs are nowadays not much more because they only occur in an advanced stage of the condition. People consult a doctor with complaints nowadays much faster so that the disease can be treated at an earlier stage.
Graves disease treatment
In order to treat hyperthyroidism by Graves disease is in practice always first selected for a drug blocking of the thyroid gland. These thyroid blocking agents, which are called antithyroid agents, inhibit the production of thyroid hormone, so that after a few weeks, and often even reduce the symptoms disappear. That it takes a few weeks before has the effect, is due to the fact that there is still a supply of thyroid hormone is present which will be released despite the medication. These antithyroid drugs, of which carbimazole and methimazole (also known as Strumazol) are the most important, are then given in doses sufficient is achieved a normal amount of FT4 in the blood.
After one year, will be then checked whether the blocking of the thyroid gland, ensures that it is also go back to normal operation (or there healing has occurred). This is in most cases not the case, then there are two subsequent treatment options are:
- Destruction of (part of) the thyroid cells with radioactive iodine (the swallow).
- Surgical removal of (part of) the thyroid gland.