Cardiac involvement is dependent on the cross-reaction of antibodies directed against M proteins produced by bacteria with human proteins present in the myocardium or endocardium (although acute rheumatic fever may present as pancarditis with additional involvement of the pericardium). This results in generalized inflammation in the heart, producing acute erosions and vegetations with fibrin deposition in the mitral valve that may be followed by chronic changes over years to decades, including shortening of the chordae tendinae and thickening or fusion of the mitral leaflets, leading to a severely compromised "buttonhole" or "fish mouth" valve.In 70% of cases rheumatic heart disease involves only the mitral valve, while 25% of cases involve both the aortic and mitral valves. Involvement of other heart valves without damage to the mitral is exceedingly rare. Mitral stenosis is almost always caused by rheumatic heart disease. Less than 10% of aortic stenosis is caused by rheumatic heart disease. Rheumatic fever can also cause chronic mitral and aortic regurgitation.While developed countries once had a significant burden of rheumatic fever and rheumatic heart disease, medical advances and improved social conditions have dramatically reduced their incidence. Many developing countries, as well as indigenous populations within developed countries, still carry a significant burden of rheumatic fever and rheumatic heart disease and there has been a resurgence in efforts to eradicate the diseases in these populations. Among persons who have experienced rheumatic fever, long-term intramuscular antibiotic therapy is used as secondary prophylaxis against additional streptococcal infections, which can contribute to progression of rheumatic heart disease.
20% of people with lupus will have a parent or sibling who already has lupus or may develop lupus. about 5% of the children born to individuals with lupus will develop the illness. United Kingdom
Females in the UK are seven times more likely to be diagnosed with SLE than males. The estimated number of females in the UK with SLE is 21,700, and the number of males is 3000 — a total of 24,700, or 0.041% of the population. SLE is more common amongst certain ethnic groups than others, especially those of African origin. United States
Lupus occurs from infancy to old age, with peak occurrence between ages 15 and 40. Lupus affects females in the US 6 to 10 times more often than males. Prevalence data are limited. Estimates vary and range from 1.8 to 7.6 cases per 100,000 persons per year in parts of the continental United States. Culture and society
In the early seasons of the television show House, members of the eponymous characters medical team often suggested lupus as a diagnosis for their patients, only to be rebuked. The rarity of legitimate lupus diagnoses in the show eventually became described as a running gag. See also
List of cutaneous conditions
List of target antigens in pemphigoid
List of immunofluorescence findings for autoimmune bullous conditions
List of human leukocyte antigen alleles associated with cutaneous conditions
List of people with lupus

References


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