The thymus is a gland that plays a very important role in the body - it is responsible for the proper development of the immune system. When the functioning of the thymus is disturbed, e.g. by its hypertrophy, many diseases, including potentially fatal ones, may develop.
The thymusis a gland that is part of the body's immune system. It is located behind the sternum, in the mediastinum, and is made of a cortex divided into lobules and a core. The thymus is already developing in utero. After about 2 years of growth, it reaches its largest size (weighs about 15 grams). After this period, mainly due to sex hormones, it gradually disappears and is replaced by adipose tissue. In an elderly person, the thymus weighs about 5 grams.
What is the function of the thymus?
The thymus is responsible for the proper development of the immune system by controlling the development of peripheral lymphatic tissues (lymph nodes, spleen).
The thymus prevents the development of allergies, affects reproductive ability, growth and metabolism.
In addition, T lymphocytes mature in the thymus. The gland is responsible for the elimination of autoreactive lymphocytes, ie those that could attack the cells and tissues of the body, and leaving those that can correctly recognize foreign tissues (the phenomenon of the so-called central tolerance). The latter, already ripe, are sent to the peripheral lymphatic tissues and inhabited them.
Consequences of thymus dysfunction
The thymus is an organ susceptible to the action of antibiotics, stress, excess estrogens in contraception and steroids. She also reacts poorly to alcohol abuse, smoking or taking drugs, which may lead to pathological changes in the thymus, e.g. thymus hyperplasia (also of a cancerous nature).
Thymus hyperplasia, with increased activity, usually causes myasthenia gravis, but it can also appear in the course of other diseases, such as:
- systemic lupus
- hyperthyroidism
- aplastic anemia.
The cause of thymic hyperplasia may also be neoplasms: thymoma and lymphomas. About 10-15 percent of patients with myasthenia gravis are diagnosed with thymoma.
In turn, diseases related to thymic atrophy include di Georg's syndrome and SCID syndrome.