A patient with metabolic acidosis has a low bicarbonate level and a high anion gap. What is the most likely cause of this condition?

A Diarrhea with excessive loss of bicarbonate ions
B Lactic acidosis due to tissue hypoxia ✓
C Renal failure with accumulation of sulfates and phosphates
D Aspirin overdose with increased production of acidic metabolites

Explanation

Lactic acidosis due to tissue hypoxia is a common cause of metabolic acidosis with a high anion gap. This occurs when tissues are not receiving enough oxygen, resulting in the production of lactic acid and other acidic metabolites.

Source

Harrison's Principles of Internal Medicine
Electrolytes and Acid-Base Balance Acid-Base Physiology Metabolic Acidosis Hard MEDICAL Confidence: high