Pyroglutamic acidosis is a cause of increased anion gap metabolic acidosis in patients receiving therapeutic doses of acetaminophen on a chronic basis. Clinical manifestations are limited to mental status changes and increased anion gap metabolic acidosis. The syndrome most commonly occurs in patients with critical illness, poor nutrition, liver disease, or chronic kidney disease as well as in persons on a vegetarian diet. Diagnosis can be confirmed by measuring urine levels of pyroglutamic acid.