Pyroglutamic acid-induced metabolic acidosis: a case report.

High anion gap metabolic acidosis due to pyroglutamic acid (5-oxoproline) is a rare complication of acetaminophen treatment (which depletes glutathione stores) and is often associated with clinically moderate to severe encephalopathy. Acquired 5-oxoprolinase deficiency (penicillins) or the presence of other risk factors of glutathione depletion such as malnutrition or sepsis seems to be necessary for symptoms development. We report the case of a 55-year-old women who developed a symptomatic overproduction of 5-oxoproline during flucloxacillin treatment for severe sepsis while receiving acetaminophen for fever control. Hemodialysis accelerated the clearance of the accumulated organic acid, and was followed by a sustained clinical improvement.