What is hypothyroidism?
Hypothyroidism is a deficiency of thyroid hormones, there are several possibilities:
- A condition in which the thyroid itself can not make enough thyroid hormones (thyroxine and tri-jew thyronine); primary hypothyroidism
- A disorder of the pituitary gland, which regulates the functioning of the thyroid gland so the production of thyroid hormone; secondary hypothyroidism
- A disorder of the hypothalamus which largely regulates the functioning of the pituitary gland; tertiary hypothyroidism.
Iodine
In the past, a common cause (eg Switzerland, the Netherlands and the area around Kampen) iodine deficiency in the diet. Iodine is essential in the production of the thyroid hormones. Iodine deficiency leads to an endemic goiter and hypothyroidism. In some countries, this is still a major cause (Pakistan). When using iodized salt (Jozo) for cooking can be no shortage. In the Netherlands is also used iodized salt by bakers, which endemic goiter here practically no longer existent, although it is still seen among the immigrant population.
The main cause of primary hypothyroidism in the Netherlands is now the Hashimoto's disease, an autoimmune disease of the thyroid.
Causes of hypothyroidism
Possible causes of hypothyroidism include:
- Hashimoto's thyroiditis
- Treatment with radioactive iodine
- The use of iodine-containing drug
- After an operation in which the thyroid gland is removed (thyroidectomy)
- Thyroid inflammation (thyroiditis)
- A congenital defect (congenital hypothyroidism, this can lead to cretinism).
- Insufficient iodine in the diet (endemic hypothyroidism)
Hypothyroidism symptoms
Often a lot of vague symptoms that are not directly taken seriously by doctors, or the symptoms are attributed to psychological problems. Patients are some shivering, some are slow and tired more quickly, there may be a degree of constipation. The voice is a little lower and krakeriger, and there is often a somewhat typical facial shape and look, which is especially evident when comparing a photo with a photo from the time the patient was still good. The menstrual cycle can be upset. Depressive symptoms are frequently attributed to hypothyroidism, however, despite extensive research, the relationship between depression and hypothyroidism still ambiguous. In several large studies, there seems to be no connection between depression and hypothyroidism.
Possible symptoms are:
- fatigue
- chilliness
- goiter
- dry, cold, pale yellow skin
- slowness in thinking and acting
- myxoedema (e.g., of the face, eyelids, and thick ankles)
- eyebrow Loss
- hair loss and brittle hair
- slow speech
- weight gain
- amnesia
- impaired concentration
- shortness of breath (shallow breathing) distress
- hoarse, croaking voice
- muscle weakness
- apathy
- psychoses - sometimes act paranoid images.
- constipation
- fluid retention in limbs
- deafness
- nervousness
- fragile, brittle nails
- stiff, aching muscles and joints, especially in the arms, legs, hips and hands
- carpal tunnel syndrome
- heavier menstrual
- tepeluitvloed
- decreased sex drive (libido)
- fertility disorders
- precocious puberty (precocious puberty)
- heart problems (arrhythmias)
- eye problems (Exophthalmos)
- also classic symptoms that occur in hyperthyroidism may occur.
Congenital hypothyroidism
In congenital hypothyroidism occurs a complex of phenomena that is designated as cretinism - a typical face, dwarfism and severe to profound mental retardation. In areas with iodine deficiency was previously not rare; nowadays it is usually a congenital defect that if it is good with the heel prick is detected within a week of birth, and by early administration of thyroid hormone usually a normal physical and mental development can be guaranteed. The congenital form is quite rare, about 70 children are detected each year in the Netherlands, 1 in 3000 births.
Hypothyroidism Diagnosis
Diagnostics is carried out by determination of the active thyroid hormone T3 and / or for the phase thereof (T4), and of the regulating pituitary hormone (TSH: thyroid stimulating hormone). This can be in a clinical chemistry laboratory, where the free T4 (FT4), free T3 (FT3) and TSH are determined.
When blood too little thyroid hormone (FT3 and FT4) is, there is a hypothyroidism. In the diagnosis may then be made a distinction between primary, secondary and tertiary hypothyroidism. This requires TSH levels of interest.
- When there is an amount of TSH in the blood is higher than normal (the pituitary stimulates the thyroid gland so more than normal), there is a problem in the thyroid gland (primary hypothyroidism): the problem is located in the thyroid gland itself. Although the thyroid gland is stimulated, he is not able to (sufficiently) to release thyroid hormone.
- The pituitary TSH gives off when the thyroid should go give his thyroid. When there is little thyroid hormone in the blood and low TSH, then there is a problem with the stimulation of the thyroid gland (secondary hypothyroidism), because normally the pituitary with a low amount of thyroid hormone would stimulate the thyroid by TSH. Now the thyroid gland is not stimulated, he will also give little hormone.
In the diagnosis can also be made a distinction between the free hormone (FT4), and the total amount (including the bonded part). When there is a low amount of FT4 is normal but a total amount of T4, then there is a bonding problem: the blood protein albumin binds too much thyroid hormone. Conversely, too much FT4 course, you can be normal and total T4 than too little tied there.
To summarize: at low T3 / T4 exists hypothyroidism. When TSH is elevated and T3 / T4 decreased, the cause lies in the thyroid. TSH is reduced, then the problem is with the control (hypothalamus and pituitary). TSH is elevated but the T3 / T4 normal then there may be a latent hypothyroidism (sign).
When a problem thyroid autoantibodies often be determined by the thyroid gland.
Hypothyroidism treatment
The treatment of hypothyroidism with a non-functioning as the cause thyroid, consists of a small daily dose of the synthetic thyroid hormone levothyroxine. This generally gives a rapid improvement of symptoms. The patient should continue to use the hormone for life. Although the treatment is lifesaving quality of life of these patients will not always return to the level before the condition. A small proportion of complaints also holds good at initiation of therapy, which really is not well understood. One reason for this could lie in the inability of the current treatment methods (such as hormone replacement in hypothyroidism) to mimic the biological thyroid function.
Sometimes, it may set the proper amount of levothyroxine or synthetic thyroid hormone for a long time to complete. Partly because the Hashimoto may still be active, causing the thyroid 'rocks', partly because there are many misconceptions exist, doctors and even specialists about what his right blood values. The TSH should ideally be set to less than 1, but should not be unmeasurable, because that may result in bone loss. On the other hand there are many people who do not perceive any difference between different doses of thyroid hormone. The setting takes place especially on the TSH.
The treatment of hypothyroidism with iodine deficiency as a cause consists of additional iodine supplementation. This deviation occurs in the Netherlands actually not among the indigenous population.