RHEUMATIC FEVER

 

RHEUMATIC FEVER

Rheumatism is used to describe inflammation of the joints, muscles and fibrous tissue. So rheumatic fever is a type of inflammatory disease that can damage the heart tissue and can lead to rheumatic heart disease.

Rheumatic fever is an acute condition occurring as a rare complication of untreated throat infection caused by Group A Beta Haemolytic Streptococcus affecting the child's joints, heart, skin, and brain characterized by high fever, polyarthritis, carditis, subcutaneous nodules, erythema marginatum, and Sydenham’s chorea.

The peak incidence occurs between 5-15 years, but affects even the very young beginning from the age of three. First attacks are rare after adolescence. The risk factors may include: age of 5-15 years, gender as it occur in both sexes but slightly more in females, insufficient nutrition, and untreated throat infection.

The pathogenesis mechanism of acute rheumatic fever are not completely understood, but in order for rheumatic fever to occur, it appears that a throat infection caused by Group A Beta Haemolytic Streptococcus must occur in a host.

Rheumatic fever develops in children and adolescents following untreated throat infection with Group A Beta Haemolytic Streptococcus. These organisms will first attach to the epithelial cells of the upper respiratory tract and produce enzymes called 'STREPTOLYSIN' that allows them to damage the epithelial cells and invade the tissues. Other than that, these microorganisms are covered with 'M Protein' which is highly antigenic. This means that the immune system sees it and recognizes it as a foreign molecule.

The immune response will be activated by producing antibodies against these proteins "M proteins of the bacteria". But again unfortunately the immune antibodies mistakenly further attack the cells of the heart, joints, skin and brain because the M Protein covering the bacteria is similar to that of the heart, joints, skin and brain. This is the reason why rheumatic fever is sometimes called an AUTOIMMUNE DISEASE. This will then lead to inflammation of the joints causing polyarthritis, inflammation of the heart called carditis, skin lamps causing subcutaneous nodules, red rash called ERYTHEMA MARGINATUM, and rapid movement of the face and arms called SYDENHAM'S CHOREA. The inflammation may heal causing fibrosis of the heart valves causing rheumatic heart disease.