As effective as the body's own defense mechanisms usually are, it is so dangerous if the regulatory mechanisms fail and the immune system is directed against the body's own tissue. An important member of the defense force are the T-cells, which were trained in the thymus during childhood and adolescence to test and recognize the body's own MHC identity papers.
How does an immune deficiency disease develop?
For reasons not yet clarified, these T cells can become saboteurs: Instead of attacking foreign invaders, they plunge onto body tissue and destroy its cells. In doing so, they draw additional defense cells on their side, so that the body's own structures are treated like antigens of foreign cells and subsequently exposed to a massive attack.
The immunoglobulins directed against the body's own tissue are also called autoantibodies (auto = self). While the body's repair crew does its best to repair the damage, it's on the losing track - sooner or later the attacked organ will be destroyed to lose its function.
Another consequence is that the immune system by its permanent attacks in the wrong place no longer has sufficient forces for its actual tasks. This is why both external and cancerous cells can spread from the inside and lead to corresponding diseases - in other words, symptoms of an immune deficiency disease develop in addition.
Hereditary factors and environmental factors
The cause is thought to be a combination of innate receptivity and certain environmental factors, which means that certain triggers such as stress, pregnancy, or infection only lead to autoimmune disease in those individuals who have a genetic predisposition to it.
When exactly and why it then comes to a disease is still unclear. However, it is known that certain pathogens can trigger an autoimmune disease, namely, when their surface is very similar to the structure of the body's own cells. If the immune system now forms antibodies against the germ, these also attack the similar endogenous tissue.
This is the case, for example, with rheumatic fever: antibodies against certain streptococci (eg scarlet fever) are later also directed against the joints, kidneys or myocardial tissue. But this probably only happens to people who have a hereditary predisposition.
The extent to which the psychological aspect plays a role, not only in the management and the course, but also in the development of the disease, is shared by the opinions.
Autoimmune diseases usually start between the ages of 20 and 50 years. The symptoms that occur in detail depend on the tissue against which the autoimmune and inflammatory process is directed. Currently, about 60 autoimmune diseases are known, which are either limited to specific organs (organ specific) or manifest in the entire body (systemic), for example, because they are directed against vessels, joints or connective tissue; both forms can be mixed (intermediate).
Typical examples of affected tissue are:
- Organ-specific autoimmune diseases: diabetes mellitus type 1 (pancreas), multiple sclerosis (nerve cells), glomerulonephritis (kidney), Hashimoto's thyroiditis (thyroid), Basedow's disease (thyroid), chronic gastritis (stomach), ulcerative colitis (colonic), vitiligo ( Skin), Addison's disease (adrenals)
- Systemic autoimmune diseases: Churg-Strauss syndrome (vessels), collagenosis (connective tissue), rheumatoid arthritis (connective tissue of joints and tendons), psoriasis (skin, joints, fingernails).
The diagnosis is made primarily by determining the antibodies in the blood - which are examined depends on the symptoms and the suspected diagnosis.