After extensive oral surgery, a 68-year-old patient who had rheumatic fever as a child and who did not take the prescribed perioperative prophylactic antibiotics subsequently developed subacute infective endocarditis. Which of the following is the most likely causative agent?

Question

Quizplus · Accepted Answer

Viridans streptococci, which are part of the normal oral flora in humans, are noted for their ability to attach to damaged heart valves when they enter the circulation after oral surgery. If you answered Strep. pyogenes, the original trigger for rheumatic fever was an untreated Strep. pyogenes pharyngitis. Each additional exposure creates the risk of additional damage. So if his school-age grandkids were coming for a week during Kwanza, then he would probably need to have prophylactic antibiotics. But the question only asks about major dental work.

After Extensive Oral Surgery, a 68-Year-Old Patient Who Had Rheumatic