Bacterial Infections USMLE Step 1 Practice Question
A 58-year-old woman with recurrent urinary tract infections presents with acute left flank pain and gross hematuria. Vital signs show BP 138/82, HR 94, RR 18, temperature 37.8°C, SpO2 98% on room air. Urinalysis demonstrates pH 8.5, numerous struvite crystals, and pyuria; serum creatinine is 0.9 mg/dL. CT scan reveals a branching staghorn calculus filling the left renal pelvis. She denies dysuria. Which organism most likely caused these recurrent infections?
Answer choices
- AKlebsiella pneumoniae
- BEscherichia coli
- CEnterococcus faecalis
- DPseudomonas aeruginosa
- EProteus mirabilisCorrect answer
- FStaphylococcus saprophyticus
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