Profound metabolic acidosis from pyroglutamic acidemia: an underappreciated cause of high anion gap metabolic acidosis

CJEM. 2010 Sep;12(5):449-52. doi: 10.1017/s148180350001263x.


The workup of the emergency patient with a raised anion gap metabolic acidosis includes assessment of the components of “MUDPILES” (methanol; uremia; diabetic ketoacidosis; paraldehyde; isoniazid, iron or inborn errors of metabolism; lactic acid; ethylene glycol; salicylates). This approach is usually sufficient for the majority of cases in the emergency department; however, there are many other etiologies not addressed in this mnemonic. Organic acids including 5-oxoproline (pyroglutamic acid) are rare but important causes of anion gap metabolic acidosis. We present the case of a patient with profound metabolic acidosis with raised anion gap, due to pyroglutamic acid in the setting of malnutrition and chronic ingestion of acetaminophen.

Publication types

  • Case Reports

MeSH terms

  • Acetaminophen / poisoning*
  • Acid-Base Equilibrium
  • Acidosis / etiology*
  • Acidosis / therapy
  • Adult
  • Diagnosis, Differential
  • Female
  • Humans
  • Opioid-Related Disorders / complications
  • Opioid-Related Disorders / rehabilitation
  • Pyrrolidonecarboxylic Acid / metabolism*


  • Acetaminophen
  • Pyrrolidonecarboxylic Acid