52-year-old healthy female presents to the hospital for 3 weeks of intermittent fever and progressive dyspnea on exertion. History only notable for multiple dental procedures in recent months.
Exam demonstrates new diastolic murmur, rales in the lung bases, and lower extremity edema. Echocardiogram reveals a large mitral vegetation.
Blood cultures are obtained and return positive in 72 hours with a morphology of gram-positive cocci in chains. This is streaked on blood agar plate but only grows in the presence of Staphylococcus aureus as pictured.