Bacteriology USMLE Step 1 Practice Question
A 44-year-old woman with type 2 diabetes mellitus comes to the physician with a 3-day history of fever, right calf pain, and swelling. Her temperature is 38.7°C (101.7°F). Physical examination shows a 5 x 6-cm erythematous, warm, raised skin lesion with well-defined margins over the right upper posterior calf. The organism isolated from the lesion forms large mucoid colonies on blood agar. Further evaluation shows that the organism has a thick hyaluronic acid capsule. The causal organism of this patient's condition is most likely to have which of the following additional characteristics?
Answer choices
- AGamma hemolysis
- BSolubility in bile
- CResistance to novobiocin
- DSusceptibility to bacitracinCorrect answer
- ENegative pyrrolidonyl arylamidase test
- FPositive coagulase test
- GResistance to optochin
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