Regarding the functioning problems of the thyroid gland, dysthyroidism has multiple causes and symptoms. The thyroid gland is a small gland located at the base of the neck that secretes several hormones that are involved in the regulation of metabolism. Explanations.

Dysthyroidism is a malfunction of the thyroid gland in its function of secreting hormones, especially thyroid hormones. It often affects women after 60 years, but sometimes also younger subjects for certain pathologies of the thyroid gland such as autoimmune diseases which will destroy the cells of the thyroid gland. The hormones secreted by this gland located at the base of the neck, under the glottis, will regulate the metabolism.

When these thyroid hormones are secreted in too large quantities, the metabolism will speed up with the manifestation of many symptoms (fever, tremor, weight loss, anxiety, increased heart rate, etc.). Conversely, if the level of these hormones decreases in the blood, the metabolism will slow down causing a feeling of cold, weight gain, slowing down of thought and movements (psychomotor slowing down). 

There are several possible causes for the manifestation of dysthyroidism. Some will cause an acceleration of the metabolism (hyperthyroidism), others a decrease in the metabolism (hypothyroidism), the last will be at the origin of alternation between hyper and hypothyroidism. Among these causes to look for are:

• Graves’ disease which is linked to the presence of antibodies that stimulate the production of thyroid hormones. It combines hyperthyroidism (fever, tremor, weight loss, anxiety, increased heart rate, etc.), exophthalmos (red eyes that protrude a little from the eye socket), an increase in the size of the thyroid gland (goiter) and sometimes difficulty in turning the eyes (oculomotor deficit);
• a toxic adenoma of the thyroid gland or several toxic nodules which autonomously secrete, most often in excess, thyroid hormones. The intake of iodine through the diet can promote this hypersecretion and symptoms of hyperthyroidism;
• subacute lymphocytic thyroiditis (inflammation of the thyroid gland) which sometimes occurs after childbirth and will gradually destroy the cells of the thyroid gland. After a brief period of hyperthyroidism, hypothyroidism will succeed which will rarely persist;
• De Quervain’s subacute thyroiditis which is locally painful, inflammatory in origin, often post-viral, with fever, pain in the area of ​​the thyroid gland and sometimes swelling of the gland. Hyperthyroidism will then be followed by hypothyroidism which will return to normal after a few weeks in most patients;
• hyperthyroidism caused by taking a medicine prescribed in cardiology, amiodarone, which will give the symptoms of hyperthyroidism;
• Hashimoto’s chronic hypothyroidism which is an autoimmune disease destroying the thyroid tissue which affects women (7 women for 1 man) and will give the symptoms of hypothyroidism (a feeling of cold, weight gain, slowing down of thought and movement (psychomotor slowing);
• Hypothyroidism following surgery removing part of the gland, radiotherapy on the thyroid region, after taking radioactive iodine or drugs (lithium, iodine, interferon, antithyroid drugs, etc.);
• Congenital hypothyroidism (1 in 4 births) which are detected at birth.

The first step in diagnosing dysthyroidism is questioning for symptoms of hyper or hypothyroidism. The clinical examination will sometimes find:

• speeding up or slowing down;
• heart problems such as heart or coronary insufficiency;
• hypertension or on the contrary hypotension (too low blood pressure);
• a goiter;
• exophthalmos;
• a fever or on the contrary a low temperature (hypothermia less than 36 °);
• anxiety or even a state of confusion or a psychomotor slowing down or even a comatose state;
• severe fatigue (severe asthenia).

Faced with such symptoms, an assessment will be carried out with, at the start, the dosage of TSH (thyroid stimulating hormone) which is the hormone that stimulates the production of thyroid hormones by the thyroid gland, free T4 which is one of the hormones produced. by the thyroid gland. 

The other biological or radiological examinations requested will depend on the suspected disease (thyroid ultrasound, thyroid nodule biopsy puncture, specific antibody dosage, etc.).

Treatments for dysthyroidism will depend on the diagnosis. They may range from biological observation of thyroid hormone levels in the presence of subacute lymphocytic or subacute De Quervain thyroiditis, to the prescription of thyroid hormones (Levothyrox, etc.) in the face of hypothyroidism in the elderly, that radioactive iodine or drugs that block the secretion of thyroid hormones in Graves’ disease or even surgery to reduce the size of the thyroid gland.

In all cases, these strategic diagnostic and therapeutic options will initially be entrusted to a doctor specializing in endocrinology, in particular for hyperthyroidism.