title: Increased anion gap metabolic acidosis as a result of 5-oxoproline (pyroglutamic acid): a role for acetaminophen.
abstract: The endogenous organic acid metabolic acidoses that occur commonly in adults include lactic acidosis; ketoacidosis; acidosis that results from the ingestion of toxic substances such as methanol, ethylene glycol, or paraldehyde; and a component of the acidosis of kidney failure. Another rare but underdiagnosed cause of severe, high anion gap metabolic acidosis in adults is that due to accumulation of 5-oxoproline (pyroglutamic acid). Reported are four patients with this syndrome, and reviewed are 18 adult patients who were reported previously in the literature. Twenty-one patients had major exposure to acetaminophen (one only acute exposure). Eighteen (82%) of the 22 patients were women. Most of the patients were malnourished as a result of multiple medical comorbidities, and most had some degree of kidney dysfunction or overt failure. The chronic ingestion of acetaminophen, especially by malnourished women, may generate high anion gap metabolic acidosis. This undoubtedly is an underdiagnosed condition because measurements of serum and/or urinary 5-oxoproline levels are not readily available.
authors: Department of Internal Medicine, Baylor University Medical Center, 3500 Gaston, Dallas, TX 75246, USA. fenvesa@dneph.com
authors: Andrew Z
authors: AZ
authors: Fenves
authors: Haskell M
authors: HM
authors: Kirkpatrick
authors: Viralkumar V
authors: VV
authors: Patel
authors: Lawrence
authors: L
authors: Sweetman
authors: Michael
authors: M
authors: Emmett
mesh_terms: D000082:Acetaminophen / Q000009:adverse effects*; D000137:Acid-Base Imbalance / Q000139:chemically induced*; D000138:Acidosis / Q000139:chemically induced*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008875:Middle Aged; D011761:Pyrrolidonecarboxylic Acid / Q000378:metabolism*
chemical_list: D000082:Acetaminophen; D011761:Pyrrolidonecarboxylic Acid