Electrolyte Disorders USMLE Step 1 Practice Question
A 35-year-old woman on long-term proton pump inhibitor therapy presents with weakness and recurrent palpitations. She has had two prior admissions for torsades de pointes. Laboratory studies show magnesium 1.0 mEq/L, calcium 7.8 mg/dL, and potassium 3.2 mEq/L. Which of the following is the most likely primary abnormality driving this constellation?
Answer choices
- AHypomagnesemiaCorrect answer
- BHypophosphatemia
- CHypercalcemia
- DHyperchloremia
- EHypernatremia
- FHypokalemia
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