Acid-Base Disorders USMLE Step 1 Practice Question
A 45-year-old woman with idiopathic intracranial hypertension is started on acetazolamide. Two weeks later she presents with fatigue and mild paresthesias. Vital signs show BP 128/82, HR 88, RR 16, temperature 37°C, SpO2 98%. Laboratory studies reveal bicarbonate 18 mEq/L, serum potassium 3.2 mEq/L, and normal anion gap. Chest X-ray shows no acute cardiopulmonary process. Which acid-base abnormality is most likely developing with this therapy?
Answer choices
- ARespiratory alkalosis
- BAnion gap metabolic acidosis
- CMetabolic alkalosis
- DRespiratory acidosis
- ENonanion gap metabolic acidosisCorrect answer
- FMixed metabolic acidosis and respiratory alkalosis
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