Definition
A swelling is a tissue protrusion caused by various causes, which can occur in different parts of the body. Swelling is often combined with a redness and also with pain from pressure.
Causes of swelling
There are numerous causes of swelling. Probably the most common cause is inflammation, which in principle can occur in all regions of the body. During inflammation, the immune system is activated by the immigration of pathogens.
Thereupon cells of the blood, which are responsible for the immune response, but also other substances, so-called mediators, are brought into the inflammation area. In order to bring as many cells of the immune system as possible to the site of action as quickly as possible, the flow of blood into the area is accelerated, resulting in vascular dilatation. Inflammatory fluid accumulates in the area where the pathogens have entered.
As a result, the area swells and also reddens. Swelling can also be caused by a non-inflammatory edema. Here, an influx of fluid occurs for various reasons.
The most common cause is congestion in the area of the lymph vessel system. If the leg is bent for a long time, for example, the lymph fluid may not be able to drain off in the usual way and accumulate around the blood vessel, which can lead to these swellings. Unilateral swelling in the leg area can also always be an indication of thrombosis and must be clarified.
and recognize thrombosis An allergic reaction can also cause tissue swelling due to fluid. In addition to the inflammatory and non-inflammatory oedemas, where increased fluid leads to swelling of the body area, there may also be swelling due to tissue proliferation. In the case of tumor formation, for example, diseased tissue proliferates to such an extent that swelling in this area occurs.
However, a tumor is not always to blame for the proliferation of tissue under the skin. Infections, for example, can also cause a swelling of lymph nodes, which are enlarged and have to be palpated in the classic areas of the body, such as the armpits or neck, causing swelling. In some cases, edema may also occur due to reduced excretion.
For example, patients whose kidneys are not working properly often have kidney related edema in one part of the body. The reason is reduced protein production by the kidneys. As a result, there is less protein in the bloodstream and the fluid is drawn from the blood vessels to the periphery, which can lead to swelling of the tissue.
