Inflammation is the process involving the cells and chemicals released by the Immune system. It is the appropriate response of the body to any tissue injury, and is largely, the responsibility of the Immune system.
It is useful to differentiate inflammation and infection as there are many pathological situations where inflammation is not driven by microbial invasion.
There are many varied causes of inflammation. The main ones are:
- Tissue trauma (e.g. fractured bones, bruising from a fall)
- Death of cells due to anoxia (e.g. Strokes and Heart Attacks)
- Autoimmune diseases
- Allergic reactions (e.g. Hayfever)
Cells of the Immune system are attracted to the affected areas in an attempt to clear up any unwanted particles - infective microbes, dead tissue cells, blood (bruising) from tissue trauma.
The inflammatory process also initiates the process of wound and tissue healing. In certain circumstances however, the inflammatory process can damage the healthy cells surrounding the area of infection. These unfortunate cells are ‘caught up’ in the infective / inflammatory process, and can be damaged or even destroyed.
This is seen particularly with the Autoimmune illnesses where, apart from the normal tissue cells which are being inappropriately attacked, the surrounding healthy tissue is involved in the inflammatory process and become damaged.
The example of Rheumatoid Arthritis can be used to illustrate this. In this condition, the Autoimmune process appears to be directed against certain cells in the lining of the joints. The inflammatory process which results leads to an increased secretion of fluid from these joints and a swollen joint is the outcome.
This swelling puts pressure onto the surrounding tissue, and together with the spread of the inflammatory exudate (chemicals and cells), the ligaments, tendons and other structures of the joint becomes involved, and inflamed. This results in a joint which can in certain cases, be exquisitely tender and unable to perform it's normal function.