Bacterial Infections USMLE Step 1 Practice Question
A 21 year old sexually active woman comes to clinic with dysuria, urinary frequency, and suprapubic discomfort for 2 days. She has no fever or flank pain. Urinalysis shows positive leukocyte esterase and nitrites are negative. Urine culture grows gram positive cocci in clusters that are catalase positive, coagulase negative, and resistant to novobiocin. Which of the following organisms is the most likely cause of this patient’s symptoms?
Answer choices
- AEscherichia coli
- BEnterococcus faecalis
- CStaphylococcus epidermidis
- DStaphylococcus saprophyticusCorrect answer
- EProteus mirabilis
- FStaphylococcus aureus
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