Synonym
Medical: Tonsille(n) Latin: Tonsilla
Definition
Tonsils are secondary lymphatic organs in the area of the oral cavity and throat. They serve the immune defense. In the course of bacterial colonization they can become painfully inflamed, this is colloquially called angina. An enlargement of the tonsils (hyperplasia) is also not uncommon. It occurs mainly in children and can lead to obstruction of nasal breathing, among other things.
Anatomy
Four different tonsils are distinguished: The pharyngeal tonsil and the lingual tonsil, however, are unpaired, so there is only one each. The entirety of all tonsils is called Waldeyer’s pharyngeal ring, it is a part of the body’s immune defense.
- Tonsilla pharyngealis (pharyngeal tonsil) is located in the mucous membrane of the pharyngeal roof.
- The Tonsilla palatina (palatine tonsil) is located in the rear part of the oral cavity just before the transition to the pharynx between the front and rear palatal arch.
- The tonsilla lingualis (lingual tonsil) lies at the base of the tongue in the area of the root of the tongue.
- The Tonsilla tubaria is located at the mouth of the Tuba auditiva (Eustachian tube) in the nasopharynx. The palatal tonsil and the tubular tonsil are arranged in pairs, i.e. they occur on both sides of the throat.
Histology
The tonsils belong to the mucosa-associated lymphatic tissue (MALT). They contain numerous lymph follicles that are formed by cells of the immune system. The surface of the palatal tonsil and the lingual tonsil consists of multi-layered squamous epithelium.
Their surface is greatly enlarged by numerous crypts (indentations of the surface). The surface of the pharyngeal tonsil consists of respiratory epithelium (multi-row ciliated epithelium). The pharyngeal almond and the palatal almond are separated from their surroundings by a connective tissue capsule.
Function
With the tonsils one means colloquially the four secondary lymphatic organs of the pharynx, which are called Waldeyer’s pharyngeal ring. This description means that the tonsils belong to the body’s own defense system, the immune system. Lymph nodes and spleen, as well as bone marrow, thymus and even the appendix in the intestine form this defense system together with the tonsils.
If the tonsils come into contact with an antigen via the lymph or blood, i.e. with bacteria or viruses, or other components that the body recognizes as a danger, the so-called immune response is initiated in the tonsils. This immune response takes place through cells that are located in the tonsils and are also partially produced there. These cells are called B and T lymphocytes and belong to the white blood cells.
B- lymphocytes can produce antibodies that are specifically directed against the recognized antigen. T- lymphocytes are directed against already infected cells and kill them. For this system to work, it is important that the surface area that can come into contact with antigens is as large as possible.
This is the case with the tonsils due to many deep furrows. In total, the surface of the almonds would be over 300cm2 when spread out. The active defense function of the tonsils was previously estimated to be much lower, which is why the removal of the tonsils was often performed as a preventive measure, for fear of tonsillitis.
In the meantime it is known that the tonsils play a major role as a defense organ in the immune system and that a considerable disadvantage is caused if they are removed too early. For this reason, a tonsillectomy is nowadays only performed on children who are over 6 years old. The immune system in children over the age of six is usually so developed that there is little reason not to have the tonsils removed if they cause inflammation or other problems. From the beginning of puberty, it can be assumed that the tonsils no longer have a major function, and that they slowly recede.
