A patient has an abscess with gram-positive cocci in clusters that are catalase and coagulase positive. Which organism is it?
Answer and explanation
Correct answer: A. Staphylococcus aureus
- Step 1: Coagulase positivity identifies S. aureus. Answer: Staphylococcus aureus. Why not the others: S. epidermidis is coagulase negative and the others are catalase-negative cocci in chains.
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