Acid-Base Disorders USMLE Step 1 Practice Question
A 28-year-old woman comes to the clinic because of recurrent kidney stones and progressive muscle weakness. She has a history of Sjogren syndrome. Laboratory studies show serum bicarbonate 15 mEq/L and potassium 3.0 mEq/L. Urine pH is 6.2 despite systemic acidosis. Which of the following is the most likely diagnosis?
Answer choices
- APrimary hyperaldosteronism
- BType 1 distal renal tubular acidosisCorrect answer
- CType 4 renal tubular acidosis
- DLactic acidosis
- EType 2 proximal renal tubular acidosis
- FMedullary sponge kidney
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