And whether you know...
March 3, 2012
The lymph node is body of lymphatic system which carries out function of the filter – through it the lymph which arrives from parts and body organs proceeds. In a human body there are 150 groups of lymph nodes, they are called regional.
Structure and main functions of lymph nodes
By outward lymph nodes represent formations of pinkish-gray color oval, round, fabiform, and sometimes even a tape-like form, their sizes fluctuate from 0,5 to 50 mm.
The arrangement of lymph nodes is close with absorbent vessels, and also with blood vessels, but most often – with large veins.
Course of a lymph to lymph nodes is provided on absorbent vessels which join a node from the convex party, and outflow – on the taking-out vessel which is connected with a node on the other hand. In a lymph node course of a lymph happens slowly where it filters on the internal spaces called lymphatic by sine. Sine have no free cavity, unlike vessels, they are partitioned by a network which clears a lymph during infiltration of foreign debris. Besides, proceeding through sine, the lymph is enriched with the antibodies synthesized by special cells.
The lymph which inflows in a lymph node brings alien antigens. It can provoke development of an immune response in nodes. Increase in this or that area of a lymph node depends on character of the brought antigens.
Thanks to the cleaning function, the lymph node represents a barrier to movement of cancer cells and an infection. In it lymphocytes – the special protective cells taking active part in fight against alien cells and substances are developed.
Localization of lymph nodes
Thanks to a special arrangement, lymph nodes are capable to become a barrier at cancer and an infection. So, they are inguinal area, a knee bend, an axillary hollow, an elbow bend, etc. of Limfouza, located on a neck, protect from tumors and infections the head and bodies which are located on a neck. In the same way and all other groups of lymph nodes are urged to protect any defined areas in a human body.
Disturbance of activity of lymph nodes can be caused by various reasons: cancer, immune and infectious diseases.
At diseases of immune system on lymph nodes, as a rule, the greatest influence is rendered by such diseases as a serum disease, an angioimmunoblastny lymphadenopathy, a dermatomyositis, a system lupus erythematosus, a pseudorheumatism, and also reaction to some medicines.
Increase in lymph nodes speaks about trouble of that zone near which they are. As a rule, increase in this body is connected with an infection.
- Purulent processes often bring to inflammations of lymph nodes, that is acute lymphadenitis. Inflammatory process develops because of penetration of microbes from wounds. The first symptom of increase in a lymph node – morbidity at a palpation, erubescence. If not to open a cavity in time, there can be a rupture of a cover of a lymph node and course of pus in fabric. In this case complication – a flegnoma develops.
- Increase in lymph nodes at children usually arises at tuberculosis. Usually at the same time the inflammation occurs in a chest cavity. Increase in lymph nodes and on a neck can be also observed.
- At HIV infection, as a rule, there is an increase in lymph nodes on a neck, in axillary hollows, in a stomach and on a breast.
- The illness of cat's scratch which causative agent is the microbe under the name a bartonella also quite often leads to increase in lymph nodes at children. For this disease an inherent purulent wound, and also a hyperadenosis, being most closer to not healing wound.
- The SARS can become the inflammation reason, especially at children's age. This process is result of an excess immune response in response to penetration of viruses into an organism. Usually lymph nodes in that case become painful at palpation, and their increase is insignificant.
- Venereal diseases can lead t to increase in lymph nodes in inguinal area therefore the chancre – ulcers on generative organs usually develops. Unlike other infections, at syphilis the lymph node can remain painless.
Defeat of lymph nodes can be result of both metastatic defeat of an organism, and limfoproliferativny diseases when the tumor originally proceeds from a lymph node. It is possible to carry a lymphosarcoma and a lymphogranulomatosis to limfoproliferativny diseases. At these diseases increase can happen to 3-4 cm, consolidation, painful feelings at palpation is observed.