Thyroid disorders can cause two diseases: hypothyroidism and hyperthyroidism. The consequences are important on the body and the quality of life. How to detect a thyroid disorder? What are the causes ? What treatments for thyroid disorders?
Thyroid disorder is manifested by a malfunction of the gland located at the base of the blow, the thyroid. The two main disorders of the thyroid are hypothyroidism and hyperthyroidism. How detect thyroid disorder? What are the causes a thyroid disorder? What treatments for thyroid disorder?
Definition: what is a thyroid disorder?
A thyroid disorder is characterized by a abnormal functioning of the thyroid, a gland located at the base of the neck. The thyroid produces two hormones that play a key role in regulating metabolism and affect the functioning of several organs such as the heart, muscles, nervous system or even the digestive tract. Thyroxine (also called T4) and triiodothyronine (also called T3). Certain metabolic disorders occur when the thyroid gland does not provide the proper amount of hormones in the blood. The two main thyroid disorders are hypothyroidism and hyperthyroidism. The repercussions of thyroid disorders (hypothyroidism and hyperthyroidism), if they are not taken care of quickly, can have more or less serious consequences on health.
What are the causes of a thyroid disorder?
Many causes are at the origin of a thyroid disorder:
- A autoimmune disease as in Graves’ disease (the most common hyperthyroidism), Hashimoto’s thyroiditis (the most common hypothyroidism) or spontaneous atrophic hypothyroidism;
- Of the adenomas (thyroid nodules) as in toxic adenoma or toxic multiheteronodular goitre which abnormally secrete excess thyroid hormones;
- A virus (coxsackie virus, mumps or adenovirus) in De Quervain’s thyroiditis;
- Of the medications : Cordarone®, iodinated contrast products used for medical imaging or thyroid hormones in certain illegal slimming cocktails, for example;
- A treatment : partial or total removal of the thyroid, treatment with radioactive iodine or external radiotherapy;
- A childbirth (between 6 weeks and 3 months) in postpartum thyroiditis;
- At birth due to malformation of the gland or malfunction;
- By iodine deficiency (rare in France since table salts are supplemented with iodine);
- Secondary to a disease of the pituitary or hypothalamus.
What are the symptoms of a thyroid disorder?
The symptoms of a thyroid disorder are multiple because the thyroid hormones have a role in many functions: production of energy, heat, use of elements from food (sugars, fats, proteins), functioning of muscles, heart, digestive tract, hair, etc. In children, they participate in the growth and development of the body through their action on the nervous system and the skeleton. In adulthood, they contribute to the functioning of the nervous system and the maintenance of bones.
What is hypothyroidism?
Hypothyroidism is characterized by a insufficient production of thyroid hormones. This is the most common malfunction. Hypothyroidism in infants and young children can be congenital or acquired. Congenital hypothyroidism affects about 1/2000 to 1/3000 newborns, in 10 to 20% of cases it is a hereditary form. Acquired hypothyroidism is the most common. It is usually due to a autoimmune thyroiditis (Hashimoto’s thyroiditis) and occurs later in childhood and adolescence. About 50% of affected children have a family history of autoimmune thyroid disease. Less commonly, hypothyroidism may occur after radiation therapy to the head and neck for certain cancers, or iodine deficiency. In adults, about 50% of hypothyroidism is autoimmune (including Hashimoto’s thyroiditis), about 40% are secondary to the treatment of hyperthyroidism (radioactive iodine, surgery, synthetic antithyroid drugs), and about 10% are caused by poor compliance with thyroid replacement hormone therapy, cervical radiotherapy or chest, or drug side effects (lithium, amiodarone, interferon). Hypothyroidism of central origin, linked to a disease of the pituitary gland, is rare.
What are the consequences of hypothyroidism?
Most infants with hypothyroidism are initially few or no symptoms and are only detected during newborn screening. Symptoms in infants include poor food intake and growth retardation. In older children and adolescents, symptoms are similar to those in adults, plus growth retardation and/or pubertal delay. In cases of iodine deficiency very early in pregnancy, infants may exhibit severe growth retardation, coarse facial features, intellectual retardation and spasticity. Hypothyroidism is responsible for physiological and psychological disturbances. The main symptoms are those of a general metabolic slowing : more or less intense fatigue (physical and intellectual), pallor and dryness of the skin, hypothermia (drop in body temperature), chilliness, thinning hair, with depilation and loss of eyebrows, difficulty concentrating and memory loss. There are also to varying degrees constipation, edema and weight gain despite loss of appetite, slow heart rate (bradycardia), high blood pressure, increased cholesterol levels, muscle cramps, pain and stiffness.
THE myxedema is a serious consequence of hypothyroidism that is characterized by facial edema (puffy appearance) with yellow, dry, cold skin, thickening of the tongue, and voice change (hoarse). This condition carries a risk of serious complications (coma).
What is hyperthyroidism?
Hyperthyroidism is characterized by a too much thyroid hormone released into the bloodstream. This is a rarer malfunction. The symptoms of hyperthyroidism are multiple. They vary from person to person: often rapid weight loss (in a few weeks) with a preserved appetite, acceleration of intestinal transit, nausea, thermophobia (heat is poorly tolerated) with excessive sweating and significant thirst. We also find heart palpitations, chest pain, rapid pulse and sometimes irregular, shortness of breath, trouble sleeping, fatigue, mood swings, irritability, and sometimes depression. There exists a decrease in muscle strength, and sometimes muscle volume (called amyotrophy), fine tremors in the hands, abnormal protrusion of the eyes outside the sockets (exophthalmos), associated with retraction of the eyelids giving a fixed gaze (especially in Graves’ disease). In women, periods are irregular or even absent. The most common causes of hyperthyroidism are Graves disease (3/4 of hyperthyroidism), the toxic multinodular goiter and toxic adenoma. We sometimes find the excessive administration of thyroid hormones, in particular within the framework of the treatment of a goitre.
What are the consequences of hyperthyroidism?
If left untreated, hyperthyroidism can lead to heart rhythm disturbances (tachycardia) and increase the risk of heart attack, osteoporosis in women at menopause, and lead to a thyroid crisis (thyroid hormone poisoning) which can lead to serious complications, such as heart failure or coma. On the other hand, hyperthyroidism can increase the risk of miscarriage, fetal death and pre-eclampsia serious in pregnant women.
When to consult in case of thyroid disorder?
“In case of palpation of a lump in the throat, or persistent fatiguea change in intestinal transit or appetite, a weight loss or weight gain, chilliness or difficulty tolerating the heat, or even in the event of depression or irritability, it is recommended to talk about it with your doctor, who will prescribe a thyroid check-up if necessary” says Dr. Claire Lewandowski, specializing in general medicine.
For the diagnosis and monitoring of thyroid pathologies, these are the TSH tests (thyroid stimulating hormone is a hormone produced by the pituitary gland and which acts on T3 and T4) and thyroid hormones T4 and/or T3 by means of a blood test:
- In the case of hyperthyroidism, the thyroid hormones (T3 and T4) are elevated and the TSH is very low.
- In the case of hypothyroidism, the thyroid hormones (T3 and T4) are low, the TSH is increased.
What treatments for thyroid disorder?
Treatment depends on the cause of the thyroid disorder. In many cases it is a hormone replacement therapy (temporary or permanent) with or without removal of the thyroid. Thyroid disorder may also require treatment with radioactive iodine or iodine substitution (in cases of deficiencies in particular).