What Are Lymph Node, Locations And Diseases
Humans generally have immunity against pathogens and accidental infections that is owed to the presence of lymph nodes which form a part of the lymphatic system. They behave like mechanical filters and kill and eliminate microbes present in the blood stream. The white blood cells or lymphocytes produced by these lymph nodes kill bacteria and viruses entering the body. Lymph nodes are very small organs, only about 1-2 cm in size and are found as a network throughout the body. There are about 500 lymph nodes spread across various organs in the body.
These structures are named according to the lymph node locations and relation with the body organs. The cervical lymph nodes are found in the neck or cervical region of the body and protect the tonsils and the pharynx. Axillary lymph nodes are found in the armpit and drain the chest region. Mediastinal nodes are found near the sternum and the lung sacs. The abdominal organs are drained by the mesentery nodes, and so on.
Fun Facts About Lymph Nodes
- The lymphatic system is compared to a sewer with networks or pipes to drain waste from every single body cell. The pipes in this system are defined as lymph vessels which transport clear interstitial body fluid, called lymph.
- The lymph or watery fluid helps in effective draining mechanism.
- The entire mechanism of draining is co-ordinated by muscle movements, as the lymphatic system has no specific pumping organs.
- The lymph nodes bulge out in the presence of an infection, as they have to work hard to get rid of it.
- Other protective organs such as spleen, tonsils, thymus and the adenoids are complementary to the lymph nodes to form the immune system of body.
- About 2 litres of lymph fluid circulate in the body every day while collecting, destroying and eliminating foreign agents and disease causing microbes.
- There are two types of lymphocytes or white blood cells produced in the lymph nodes, called B & T lymphocytes. The B-lymphocytes target bacteria and some viruses, whereas the T - cells attack viruses.
Functions Of Lymph Nodes
The lymphatic system behaves like a middle-man between the tissues and the blood vessels. When tissues transport impure or deoxygenated blood back to the blood stream for oxygenation, the microbes and impurities in the blood are collected by the lymphatic system, before they could enter back into the blood stream. The lymph nodes function like sewers and extract pathogens from the blood stream, which are later killed by white blood cells. The interstitial fluid that enters the lymphatic system is absorbed by lymphatic capillaries. The purified liquid is later transferred back into the cardiovascular or blood circulatory system for oxygenation. Lymph nodes also serve as the major factories of the body, where the white blood cells, the defence force of body, are synthesised. These are responsible for auto-immune response and target & eliminate infections at different locations in the body.
Diseases of The Lymph Nodes
Hodgkin's disease is one of the serious lymph nodes diseases, and it is a type of cancer, in which the lymphocytes are commonly affected and the victim with this type of cancer becomes vulnerable to many other diseases as the immune system is going be to partially or completely destroyed. The cancer can be managed with radiation therapy and medication, but the prognosis is usually poor.
Swollen Lymph Glands
Lymphadenopahty is the medical term used for the condition of swollen lymph nodes. Lymph nodes often swell up in the presence of an infection or tumour of the adjoining organs. It is also one of the main symptoms of many abnormalities and disorders of the body. Depending on the location of the swelling, the exact disease in the body can be diagnosed by the physicians, for example, nodes in the armpit swell in breast cancer.