Symptoms Of Strep Arthritis

By | October 8, 2018

Rheumatic fever heart disease

“Rheumatism� is used to describe inflammationin the joints, muscles, and the fibrous tissue, so rheumatic fever is a type of inflammatorydisease that can damage the heart tissue, and lead to rheumatic heart disease. Rheumatic fever develops after streptococcalpharyngitis, inflammation of the throat due to Streptococcus pyogenes where pyogenes literallymeans “makes pus�. The bacteria is sometimes referred to as “Group A beta hemolytic�streptococcus, and the infection itself is most often just called Strep throat. Thisparticular group of streptococcus has an antigen that lumps it into a group called “groupA�, and it also produces an enzyme called

streptolysin, that completely lyses nearbyred blood cells, or causes them rupture—rupturing red blood cells is called hemolysis, rightéAnd when those red blood cells rupture and are destroyed, it's called betahemolysis—asopposed to alphahemolysis, where cells aren't actually destroyed, they're just damagedor bruised. Some of these strep bacteria have a proteinon their cell wall called “M proteinâ€�, and this particular protein is highly antigenic,meaning the immune system sees it and recognizes it as a foreign molecule, and mounts an immuneresponse, which rightfully so, produces antibodies against these proteins. Those antibodies,though, are thought to crossreact with proteins

on some of our body's own cells, like cellsin the myocardium (or heart muscle) and heart valves, but also cells in the joints, theskin and the brain. This phenomenon, where antibodies accidentally target proteins onour own cells because they look like the proteins on foreign cells, is called molecular mimicry,and is an example of what's called a type 2 hypersensitivity reaction. Once bound tocardiac tissue, the antibodies activate nearby immune cells, which causes a cytokinemediatedinflammatory response and tissue destruction. Obviously though, not everyone that gets strepthroat gets rheumatic fever, and it's actually only a small minority that get it, estimatedaround 3%, and it's more likely in children

or people in areas of poverty and crowding. A lot of patients that do have rheumatic feverfrom strep, sometimes called acute rheumatic fever, will have a variety of of alfindings. The most common of which is migratory polyarthritis of the joints—where multiplelarge joints become inflamed, swollen and painful, one after another, although thisdamage isn't permanent. Secondly, some patients have pancarditis, or inflammation of all threelayers of the heart tissue. The first, endocarditis, is inflammation of the inner lining whichincludes the valves. The mitral valve is most commonly affected, although the aortic valvemay also be affected. The next is myocarditis,

inflammation of the myocardium, or heart muscle.Inflamed areas in the myocardial tissue are called Aschoff bodies, which are areas withfibrinoid necrosis, with immune cells like T cells and these characteristic Anitschkowcells, enlarged macrophages which have characteristic caterpillarlooking nuclei. It turns out thatmyocarditis is the most common cause of death in acute rheumatic fever because this inflammationand necrosis makes the heart wall unable to contract with full force, which results inheart failure. Finally there's pericarditis, or inflammation of the outer covering of theheart called the pericardium, which can cause pain as well as a friction rub from the inflamedvisceral pericardium rubbing against the inflamed

parietal pericardium which can be heard witha stethoscope. In addition to joint and heart problems, thehypersensitivity reaction in rheumatic fever can affect other tissues as well. Patientscan develop subcutaneous nodules, these firm lumps under the skin made up of collagen.They might also have erythema marginatum, a reddish rash that shows up as rings on thearms or trunk. Also, Sydenham's chorea, which is a set of rapid movements of the faceand the arms, from an autoimmune reaction against basal ganglia of the brain, and thisone typically won't appear until late in the disease, at least 3 months after infection.These five signs constitute the major diagnostic

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