Therapy
The therapy of hyperfunction is generally carried out primarily with thyrostatic drugs. This is the name given to drugs that reduce the production of thyroid hormones when thyroid levels are too high. Once a normal, i.e. “euthyroid”, metabolic state has been reached, further therapy depends on the type of cause: an autonomous adenoma, for example, which produces thyroid hormones continuously, can be removed surgically.
However, there is a risk that individual parts may be overlooked or cannot be completely removed. In general, a complete removal of the thyroid gland is indicated for carcinomas, as these have a high mortality rate in late stages.However, thyroid surgery can only be performed if the thyroid gland has previously been euthyroid. Radioiodine therapy is another therapeutic option: Here, a radioactive iodine isotope is administered – usually orally – which is then absorbed by the thyroid cells, thus irradiating and destroying them from within.
The special feature of this therapy concept is that only the thyroid cells absorb the radioactive iodine and the remaining body cells are not affected by the radioactive radiation. The half-life of the iodine is only 8 days. This means that in 8 days the radiation has already been reduced to half.
However, this also means that patients must remain in a radiation protection bunker for at least 48 hours after ingestion to protect their fellow human beings. An outdated method, which goes back to the American endocrinologist Henry Plummer, is “plummeting”. In the case of hyperthyroidism, large amounts of iodine are given (well over 200 micrograms per day), which causes the hormone synthesis and release as well as the iodine uptake to stop for a few days.
However, this method is no longer used today. Thyroid gland values are diagnosed in the laboratory by examination of the blood. A small amount of blood (usually 10-30 milliliters) is taken from the patient and sent to the laboratory within one day.
There the determination of the TSH takes place. The determination of the hormones T3 and T4 is much more costly and time-consuming and is only performed on special occasions. Since TSH usually represents the reciprocal value of the hormones, the determination of an under- or overfunction is also possible using TSH.
The thyroid gland values fluctuate strongly even in completely healthy patients, so that a reference range is relatively difficult to establish. A thyroid gland value outside the reference range does not necessarily mean over- or underfunction. For TSH the normal range is between 0.2 and 3.1 microU per milliliter.
The thyroid gland itself is almost always examined by the attending physician using ultrasound if under- or over-function is suspected. Since ultrasound is a cost-effective, easy-to-use and non-invasive procedure, ultrasound has become the “gold standard” in this context. By means of ultrasound – or sonography – volume, size, and any nodules or structural changes can be determined.
For further clarification, a scintigraphy is usually performed, in which radioactively marked substances such as technetium or iodine isotopes are injected and then displayed with a scanner (a gamma camera). Accumulations of certain areas in the thyroid gland or completely empty fields are called hot or cold nodules and can be the expression of an adenoma or carcinoma. For the examination of the thyroid gland values by the doctor, a small amount of blood is taken via a vein, usually in the crook of the arm.
Unlike certain other blood tests, you do not have to be fasting to get your thyroid gland values, which means that you can eat and drink normally. The only exception is for people who are already taking thyroid tablets. On the day of the blood test, these must be omitted before taking the blood sample, otherwise they will falsify the measurement result.
Only then should the tablet be taken. All other medication, such as for blood pressure, should continue to be taken as usual. During pregnancy the expectant mother needs more iodine than usual.
Thus, at least 230 micrograms of iodine are recommended daily. Furthermore, a slight enlargement of the thyroid gland is to be expected during this time – this is normal, however, and due to the increased demands on the thyroid gland. During pregnancy, normal thyroid gland function is particularly important to ensure the healthy and proper development of the child.
Depending on the time of pregnancy, slightly different limits apply. The most important hormone for determining function, TSH, should be between 2.5 and 0.1 in the first trimester of pregnancy. In the second trimester of pregnancy, however, the reference range is somewhat higher, with values between 0.2 and 3.0.
In the last three months of pregnancy, values below 0.3 are considered too low. The upper limit here is also 3.0. In the case of deviating values, the thyroid hormones T3 and T4 are usually also determined.
If these are also elevated or lowered, there is a particular risk to the child and appropriate treatment, usually in the form of tablets, should definitely be given.If TSH levels are too high, the thyroid antibodies that indicate Hashimoto’s disease (TPO-AK and TG-AK) are usually also determined, as this is the most common cause of the increase in TSH. Women who are already known to have a thyroid dysfunction must have their thyroid levels in their blood checked regularly during pregnancy. Hypothyroidism can cause serious developmental disorders in children.
Premature births or miscarriages can also occur during pregnancy as a result of low thyroid levels. Therefore, the thyroid gland values should always be clarified by the treating physician. In children, it is essential to clarify an underactive thyroid as soon as possible, otherwise developmental disorders such as dwarfism, malformations and, in the worst case, retardation (mental development that is not age-appropriate) can occur.
Iodine deficiency is the most common cause of avoidable retardation in childhood worldwide. Children with an unattached thyroid (“aplasia”) may have to take L-thyroxine daily throughout their lives. If the thyroxine is not taken for several days, symptoms such as listlessness and depression may develop in affected children.
These symptoms become worse if the child continues not to take the medicine. Monitoring thyroid levels is therefore particularly important during pregnancy and in children, as this is where the course for healthy child development is set. Women with a desire to have children and a thyroid dysfunction should be treated, as both under- and over-functioning can be responsible for the fact that this is not fulfilled.
If pregnancy does occur, there is a risk that the mother’s thyroid function will be disturbed, resulting in malformations and developmental disorders of the child or even a miscarriage. If there is a suspicion that a thyroid gland disorder may be present, women should therefore have their function clarified by a blood test at the doctor’s office. Even if no symptoms are noticed, as is often the case when only the regulatory hormone TSH is outside the normal range, the risks are increased.
The determination of thyroid gland values in the blood is also uncomplicated and fast. If these are in order, this can alleviate possible concerns. However, if they are not within the reference range, effective treatment is possible in most cases. Incidentally, the thyroid gland values of the man have no direct influence on the desire for children.