Final answer:
Rheumatic fever is a serious complication of inadequately treated pharyngitis caused by Streptococcus pyogenes. It leads to autoimmune damage, notably to the heart valves, and can cause lasting cardiac issues. Early treatment of strep throat with antibiotics reduces the risk of developing rheumatic fever.
Step-by-step explanation:
Rheumatic fever is an inflammatory disease that is a rare but severe complication of untreated or inadequately treated pharyngitis, specifically when caused by the bacterium Streptococcus pyogenes. This condition arises due to an autoimmune response where antibodies developed to fight the S. pyogenes mistakenly begin to attack the body’s own tissues, particularly heart valves, leading to carditis and possible rheumatic heart disease. Rheumatic fever typically presents itself 2-3 weeks after the onset of the strep throat infection.
The damage induced by rheumatic fever can vary: joint pain and swelling are reversible, while cardiac damage can lead to lasting issues such as scarring and stiffening of the heart valves, producing murmurs. Prompt diagnosis and treatment of the initial S. pyogenes infection with antibiotics are critical to prevent the development of rheumatic fever, which at one time was a major cause of mortality in children in the United States.
Despite being rare today in the US due to advanced medical interventions, in parts of the world where medical care is less accessible, rheumatic fever and the resulting rheumatic heart disease continue to be significant health concerns.