Following a bout of streptococcal pharyngitis, what explains the development of acute rheumatic fever despite antibiotic treatment that eradicated the bacteria?

💡 Explanation

Acute rheumatic fever arises due to molecular mimicry. Antibodies targeting streptococcal antigens cross-react with cardiac tissue because streptococcal M proteins share structural similarities with myosin; therefore, the immune system attacks the heart, rather than direct bacterial damage causing the condition.

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