Local inflammation is inflammation that occurs in an isolated area of the body, as opposed to systemic inflammation, which affects the whole body. Inflammation is the body's normal response to injuries and infections. In the case of local inflammation, the affected area typically becomes red, hot, swollen and sore. As inflammation protects the body and normally resolves by itself, treatment is not always necessary. An infection that arises inappropriately or continues for too long may require treatment with drugs such as steroids.
Causes of inflammation include accidental injuries, such as a small cut, or an insect bite. Immune system disorders, where the body reacts against itself, can also lead to inflammation. This is seen in diseases like eczema, where the skin becomes inflamed. Inflammation can also occur in response to extremes of temperature, chemical damage and an insufficient blood supply to tissues.
The symptoms of inflammation result from changes that take place at a cellular level. During the inflammatory process, white blood cells at the injury site release substances such as histamine, which trigger the changes of local inflammation. The blood flow to the damaged area increases, causing redness and warmth, and tiny blood vessels at the site become leaky. Fluid leaks out of these vessels, leading to swelling of the inflamed region. The release of certain chemicals by white blood cells affects nearby nerves, causing pain.
Local inflammation has many positive effects. It limits damage to a specific part of the body, preventing harmful substances from spreading elsewhere. The increased blood flow associated with inflammation enables helpful white blood cells to reach the injured site. Some white cells are able to remove potentially harmful agents, such as bacteria and toxic particles, by consuming them. They are also able to clean up dead tissue.
The heat that results from the increased blood flow associated with local inflammation makes it more difficult for bacteria to survive in the inflamed area. All of the signs of inflammation serve to draw a person's attention to the damaged part of the body. This helps prevent further injury, as the person becomes more likely to protect the affected area and seek treatment.
Treating inflammation may involve using medication. In the case of eczema, steroid ointments may be applied to inflamed areas of skin. This treatment suppresses the immune system's abnormal response, which is causing the disorder, and allows the skin to heal.