what is the cause of rheumatic fever?

Answer 1

Rheumatic fever is an autoimmune disease which occurs after an untreated Group A streptococcal infection, typically a throat infection. The antibodies formed against the bacteria attack parts of the body, typically the joints and the heart. This occurs because the streptococcal M antigen can stimulate B cells which are cross reactive with cardiac myosin.

Group A Streptococcus pyogenes has a cell wall that is composed of branched polymers which sometimes contain "M proteins" which are highly antigenic. The antibodies formed against these proteins sometimes cross-react with normal tissue causing damage. Depending on the site of damage, this can lead to the clinical symptoms described above.

Answer 2

The exact cause of rheumatic fever isn't clear. In a few people, it seems that when the body fights a strep throat infection, other parts of the body develop inflammation. For example, the heart valves aren't necessarily infected with the streptococcal bacteria, but they can be injured or inflamed as the body fights strep throat.

Medical research has focused on an abnormal immune system response to the antigens produced by specific types of streptococcal bacteria. One possible cause for this is the similarities between streptococcal antigens and heart valve proteins and heart muscle cells. In addition, researchers are studying whether some people have a greater genetic disposition for an abnormal immune system response to streptococcal antigens.

Answer 3

It sometimes develops in the aftermath of a streptococcal infection, usually in children or adolescents. Streptococcus causes strep throat and sometimes scarlet fever, which was once known as the red death. I had scarlet fever as a baby, but they had antibiotics by then.

Answer 4

the exact cause is not known but the most likely theory is autoimmunity"abnormal immune reaction"
streptococcusA infection will stimulate antibody formation to act against microorganisms , sarcolemma of myocardium & endocardium have surface antigens similar to streptococcus antigens so antigen+complement will react against them "type II cytotoxic reaction" which produces damage to myocardial & endocardial cells with liberation of auto-antigens which by turn stimulate auto-antibodies causing type III & type IV reactions causin gallergic granuloma
this can be proved by:
3 high titre of anti streptolysin
2 abcent microorganisms
1 penicillin prevent recurrence
also predisposing factors include:
2 hereditery predisposition
1 cold climate & low living standard