You are here: MEDICA Portal. MEDICA Magazine. Topic of the Month. Volume archives. Our Topics in 2011. February 2011: Autoimmune Diseases. Organs.
The Accidental Fight Against a Butterfly-shaped Gland
The yearly examination at a trusted general practitioner is routine. Until now, the patient has not experienced any serious physical problems. At times, solely increased periods of fatigue, restlessness, insomnia and slight weight gain trouble him. While reviewing the blood test results, the physician detects that the patient’s TSH levels, the hormones of the pituitary gland, are elevated. The hormone levels of the thyroid gland, T3 and T4, are too low. Upon closer examination, attacking antibodies can be detected in the blood. After yet another examination by a medical specialist, the diagnosis is set: Hashimoto’s thyroiditis. Unfortunately, the patient has never heard of this disease before.
An unusual name for common symptoms
The fictitious patient represents many people in Germany, because “Hashimoto“ is neither an Asian car make nor some type of martial art, but rather one of the most common autoimmune diseases in the world. A thyroid gland disorder is not a rarity, though it often is not recognized during a routine examination. “Many people are affected by this disease who have never heard of Hashimoto’s thyroiditis“, explains Barbara Schulte, President of the German Thyroid Association in Bonn (Schilddrüsenliga e.V.), the umbrella organization of support groups for thyroid patients and their relatives. The reason for this is the often frequently asymptomatic disease type and the course of the disease with varying, undetermined symptoms. Patients complain about symptoms such as sensitivity to cold, nervousness, insomnia or listlessness. At first this sounds so innocent to where follow-up examinations are in many cases not performed.
This thyroid disease was discovered during the First World War by the Japanese physician Hakaru Hashimoto and has carried his name since then. In a German magazine he reported on his medical findings, an enlarged thyroid gland, the “Struma“ or ”goiter“. The disease appeared in young people, in which the thyroid gland showed inflammatory changes.
Professor Georg Benker, specialist in internal medicine and endocrinology at the Endocrinology Center in Bochum, Germany explains: “It is important to know that this type of Struma has nothing to do with iodine deficiency, which is unknown in Japan anyway. We are also familiar in Germany with Hashimoto’s disease with an enlargement of the thyroid gland, but it is not very common. This is the so-called ”hypertrophic form (size increase) of the disease. “ Here the thyroid gland is swelling more or less due to immune processes during inflammation.
Many people however are sick from a second type of inflammation, where the thyroid shrinks. “Here the thyroid gland atrophies and loses its function during the course of the disease. This can lead to hypofunction of the thyroid gland, hypothyreosis, in varying degrees of severity“, Benker adds. Both types of the disease, the atrophic and hypertrophic forms, can also merge with each other, which is especially the case in the initial stage of Hashimoto’s thyroiditis.
Surgery Network Radiology & Nuclear Medicine - Photo Gallery 1
Wrong programming of the immune system
There is much speculation on the causes that trigger chronic autoimmune thyroiditis and the factors are still not sufficiently researched. What is known is that the immune system accidently attacks the own body by identifying the body’s own cells as “foreign“. Consequently specialized white blood cells are being produced, the lymphocytes, and antibodies, that attack somatic cells. Thus the chronic destruction takes its course. What complete functions the antibodies assume during the immune response that triggers or develops Hashimoto’s thyroiditis, is still unknown. It is certain that the cause of the disease can be attributed to an immune system dysfunction.
“Antibodies against the thyroid gland tissue are being produced, which can disrupt the function and growth of the thyroid to varying degrees. The immune system should actually prevent something like this from happening – unfortunately, we don’t know yet, why these mistakes of the immune system happen to the thyroid of all things. However, there are many different theories“, Benker carries on.
Thyroid antibodies are very common in the human organism and their number increases with advancing age. Women are more often affected than men. “Though by far the largest number of people who show these antibodies in the blood serum never experience hypofunction, or just very simple forms. This is known through a large series of research. The diagnostic findings of thyroid antibodies therefore should not be equated with having a thyroid disease“, explains Benker.
Therefore Hashimoto’s thyroiditis only is present if aside from antibodies there also is a functional impairment of the thyroid. This means: tissue changes in the ultrasonic image of a thyroid or biopsy. A diagnosis is often difficult and cannot be detected without laboratory tests. An increase in TSH hormone which regulates the thyroid will also turn out a positive result.
A dysfunctional hormonal control mechanism
The hormonal lopsidedness of the affected person leads to different symptoms. Since hormones are responsible for the communication and signal transmission, respectively, between the brain and organs and vice versa, but also between organs among each other, they play a big role in all functional sequences. The hormonal regulation however is very complicated and not completely researched.
In connection with Hashimoto’s thyroiditis is a hormone that stimulates the thyroid and is of particular importance: the thyroid-stimulating hormone, TSH. Simply put, it originates in a chain of sequences. At first the hypothalamus transmits a message in the form of a hormone, the thyrotropin-releasing hormone (TRH) to the pituitary gland (hypophysis). It is to make sure that the thyroid produces hormones. Subsequently it sends the hormone TSH into the bloodstream. The message now is directed to the thyroid gland, who is asked to produce T3 (triiodothyronine) and T4 (tetraiodothyronine). The healthy thyroid carries out the message. T3 and T4 thus enter the bloodstream and decrease the release of TRH and TSH, since the need for thyroid hormones for now is balanced. This way changes, for example a decreasing production of T3 and T4 as well as the need for thyroid hormones can be detected. The TSH level has an enormous importance for the diagnosis and evaluation of thyroid function.
If hormone levels during pregnancy are changing, female “Hashimoto“ patients should pay attention to the right adjustments of thyroid readings for fT3, fT4 and TSH. The readings should be in the standard range. “Pregnancy represents ’stress’ on the thyroid gland, because the hormone production of thyroxine needs to increase by about 30 to 50 percent. A normal supply with thyroid hormones is important for the course of a pregnancy, for example for the child’s development and to decrease the risk of miscarriage“, as known by the endocrinologist from Bochum.
Surgery Network Radiology & Nuclear Medicine - Photo Gallery 2
Side effects of thyroid disease
In some patients other autoimmune diseases can occur or already exist in conjunction with Hashimoto‘s thyroiditis. It’s not uncommon for instance for a chronic skin disease like rosacea or joint pains with rheumatic diseases to appear. However, the ranges of variations of these autoimmune diseases of the thyroid gland are varied.
Benker points out: “If a patient already has another autoimmune disease, for instance rheumatoid arthritis, the likeliness is high that he or she also has Hashimoto’s thyroiditis. This is not true in the reverse. Most people with thyroid antibodies, and there are very many of them, do not contract another autoimmune disease. “
A balanced human being
Severe forms of hypofunction are marked by an increasingly high TSH value, which normally is at most 4.0 mU/L. This needs to be well treated. “There are values of over 100 mU/L and above“, says Benker. “This type of progression however is relatively rare. The basal metabolic rate and energy consumption for example drastically decrease in these people. If such a severe hypofunction doesn’t get treated, it will lead to heart- and vascular diseases and metabolic disorders. “
The hormonal balance though should reach normal levels in every patient by taking thyroid hormones, regardless of severity of the disease. The requirements for the thyroid hormone is individually adjusted to the organism and in most cases replaces the partially or completely destroyed thyroid hormone producing cells for the rest of a person’s life. The hormone requirements are not constant during the course of one’s life, but fluctuate. That’s why drugs should time and again be newly adjusted. Based on blood test results you can then determine whether the levels are in the normal range. A TSH value of below 1.0 mU/L is ideal –of course the well-being of the patient also plays an important role.
New research approaches deal with the intake of selenium. It was discovered that taking in selenium positively influences the autoimmune process. However, it is important to have the selenium levels checked during intake intermittently. “There is a consideration on whether the disease could possibly be prevented by taking selenium. There is no scientific proof for this. Two studies have shown, that antibody concentration decreases through selenium intake“, Benker explains. So there also is no evidence whether the course of the disease can be slowed down by it or perhaps prevented.
Unfortunately, curing Hashimoto’s thyroiditis thus far is not possible. The disease is chronic, which means it persists for life and often results in the complete destruction of the thyroid gland. The developed hypofunction and the thus associated ailments can merely be regulated by intake of thyroid hormones. But patients don’t need to be afraid of such a possible course of the illness: “In many cases you can live much better without a thyroid. The patients can be adjusted better, because they don’t have an adversary anymore“, Mrs. Schulte assures us drawn on her own experience.
(Translated by Elena O'Meara)
Topic Preview March
In March our focus lies on "emergency medicine ". Here we will concentrate on the topics education and telemedicine.