Chronic Kidney Disease USMLE Step 1 Practice Question
A 47-year-old woman with recurrent urinary tract infections presents with persistent bilateral flank discomfort. Vital signs: BP 142/88 mmHg, HR 88/min, RR 16/min, Temp 37.2°C, SpO2 98% on room air. CT abdomen shows a large branching staghorn calculus in the right renal pelvis. Urinalysis reveals alkaline urine (pH 8.2) and positive nitrites. Serum creatinine is 1.8 mg/dL. No hematuria on urinalysis. Which organism type most likely contributed to stone formation?
Answer choices
- AEncapsulated gram positive cocci
- BUrease positive bacteriaCorrect answer
- CAnaerobic gram negative rods
- DAcid fast bacilli
- ESpirochetes
- FOxidase positive gram negative cocci
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