Chronic Kidney Disease USMLE Step 1 Practice Question
A 44-year-old woman with a history of recurrent urinary tract infections presents with fever (38.9°C), dysuria, and left flank pain. Vital signs show BP 128/82 mmHg, HR 102/min, RR 18/min, SpO2 98% on room air. Urinalysis demonstrates alkaline urine (pH 8.2), pyuria, and bacteriuria. Serum creatinine is 1.1 mg/dL. Non-contrast CT imaging reveals a large branching stone completely filling the left renal pelvis. She denies hematuria. Which organism is most likely responsible for this stone type?
Answer choices
- AAdenovirus
- BStaphylococcus saprophyticus
- CProteus mirabilisCorrect answer
- DEnterococcus faecalis
- EEscherichia coli
- FKlebsiella pneumoniae
See the full explanation
Get the correct-answer rationale, why each distractor is wrong, the underlying mechanism, and high-yield associations — plus adaptive practice that targets your weak areas — with a free MedBoardPRO account.