Chronic Kidney Disease USMLE Step 1 Practice Question
A 58-year-old man with chronic kidney disease presents with fatigue and dyspnea. Vital signs: BP 156/92 mmHg, HR 88/min, RR 18/min, SpO2 98% on room air. Serum creatinine is 3.2 mg/dL; eGFR is 18 mL/min/1.73m². He denies hematuria. During a research study, inulin—a substance freely filtered at the glomerulus but neither reabsorbed, secreted, synthesized, nor metabolized by the kidney—is infused. The clearance of this substance equals which of the following?
Answer choices
- AFiltration fraction
- BRenal plasma flow
- CGlomerular filtration rateCorrect answer
- DUrine flow rate
- ERenal blood flow
- FTubular secretory capacity for organic anions at the proximal tubule
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