Thymus Gland Diseases

Not commonly heard about, thymus gland is a specialized organ that is a part of the immune system. The word thymus comes from the Greek word thymos. It means heart, soul, desire, life. This word was probably coined because of the gland's location. This gland is located between the lungs in the chest. It may also arise from another Greek word thyme that means something that has a bumpy appearance.

The gland resembles a bunch of thyme, and hence may be named so. The only known function is production and education of the T-lymphocytes. These cells are very important to help the immune system distinguish between infectious cells and normal body cells. There are a few thymus gland diseases that have an effect on the immune system. These diseases are covered below.

This gland is the largest gland in the body that is most active in infants and in adolescents. This gland helps the immune system develop during the early years. So, until the T-cells are mature enough to protect the body against infectious agents till puberty, the gland continues to function. After puberty, it begins to shrink in size and most of the tissues get replaced with adipose tissues.

This is a genetic condition that is caused by deletion of a short section of chromosome 22. This disorder leads to heart defects, poor immune system, cleft palate, behavioral problems and parathyroid gland problems in children. The symptoms of DiGeorge syndrome vary according to the severity of the condition, and the part affected.

These symptoms may appear immediately after birth, or appear later during infancy or early childhood. Some of the symptoms of DiGeorge syndrome are:

• Bluish tinge on skin
• Weakness
• Poor muscle tone
• Twitching around the mouth, hands, arms, throat
• Recurrent infections
• Delay in development as well as achieving infant milestones
• Cleft palate
• Learning difficulties

Thymus gland is prone to two types of cancers. First one is a tumor, called thymoma. The cancerous cells formed in thymoma are very similar to the normal cells of thymus gland. The other cancer is called thymic carcinomas. The cells in this cancer do not resemble the normal thymus cells.

These cells are very aggressive and divide rapidly. Thus, they easily spread to other tissues. Both these cancers can exist without any symptoms. If at all the symptoms do occur, it involves cough and chest pain.

This is a rare, benign tumor that contains thymic as well as adipose tissues. This tumor does not invade or spread to the surrounding tissues or organs of the thymus gland. These tumors can grow very big and show no symptoms at all.

Also called thymus hyperplasia, it is a condition where enlargement of the thymus occurs. This condition is usually associated with myasthenia gravis.

This is an autoimmune disease that is caused by blockage of acetylcholine receptors by antibodies. This condition is often associated with thymic hypertrophy. The muscles become weak and this affects eye control, eyelid movement, chewing, talking as well as swallowing.

The symptoms vary in different patients. It includes drooping eyelid(s), double vision, shortness of breath, dysarthria, weakness of arms, hands, legs, neck muscles, etc.

Any kind of malfunction or disease related to thymus gland leads to either hypersensitivity, autoimmune disease or immunodeficiency. One of the deadly diseases associated with this gland is HIV/AIDS. The virus tends to kill the CD4+ T cells that are produced by thymus.

The virus also destroys the thymocytes that are developing in the thymus, thus, causing immunodeficiency in the body.