Chronic Kidney Disease USMLE Step 1 Practice Question
A 22-year-old woman presents with progressive fatigue and episodic muscle weakness. Vital signs: BP 118/76 mmHg, HR 92/min, RR 16/min, temp 37°C. Serum potassium 2.8 mEq/L, magnesium 1.4 mg/dL, pH 7.48 with HCO3− 32 mEq/L. Urinary calcium excretion is low. She denies diarrhea or diuretic use. Which of the following best describes her renal tubular disorder?
Answer choices
- AInherited defect of the thiazide sensitive Na Cl cotransporterCorrect answer
- BAldosterone deficiency due to adrenal destruction
- CResistance to antidiuretic hormone in the collecting duct
- DLoss of the loop Na K 2Cl cotransporter
- EConstitutive activation of the epithelial sodium channel
- FDefective alpha-intercalated cells causing impaired H+ secretion in the collecting duct
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