Bacteriology USMLE Step 1 Practice Question
A 47-year-old male with a history of sickle cell disease has had numerous hospitalizations requiring the placement of IV lines. The patient has poor peripheral venous access, and a catheter is placed in right subclavian vein. The patient subsequently develops right arm discomfort and swelling and a temperature of 40.1°C with chills. Multiple blood cultures are taken, and gram-positive cocci are isolated. The organism is catalase-positive and produces whitish colonies on mannitol salt agar. The colonies are gamma-hemolytic on sheep blood agar. Which of the following organisms is the most likely cause of this patient's symptoms?
Answer choices
- AEnterococcus faecalis
- BStaphylococcus aureus
- CStaphylococcus epidermidisCorrect answer
- DStreptococcus agalactiae
- EStreptococcus pyogenes
- FStaphylococcus saprophyticus
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