Final answer:
Rheumatic fever is a rare complication of an infection with Streptococcus pyogenes, leading to an autoimmune response that may cause irreversible damage to heart valves, known as rheumatic heart disease.
Step-by-step explanation:
Rheumatic fever is an inflammatory disease that is a rare complication which can occur following an infection with Streptococcus pyogenes, the bacterium that typically causes strep throat. This condition manifests as a result of an autoimmune response where the body's immune system mistakenly attacks its own tissues after being triggered by the strep throat infection. The most serious consequence of rheumatic fever is rheumatic heart disease, where the cross-reacting antibodies that were produced to fight off the Streptococcus pyogenes infection cause damage to heart tissues, particularly the heart valves.
One of the main concerns with rheumatic fever is that the damage to the heart valves can be irreversible and worsen with repeated attacks, which is more likely during the first 3-5 years after the initial occurrence of the disease. Joint pain and swelling may also be present, which typically resolve with time. Rheumatic fever is now rare in the United States thanks to the early diagnosis and treatment of streptococcal pharyngitis with antibiotics, but it remains a significant health issue in parts of the world where medical care is less accessible.