Symptomatic Diethylene Glycol Ingestion Successfully Treated with Fomepizole Monotherapy.

BACKGROUND: Diethylene glycol (DEG) is an industrial solvent with many uses, including brake fluids. It has also caused mass poisonings after use as an inappropriate substitute for propylene glycol or glycerin, though individual ingestions are rare. Like other toxic alcohols, DEG is metabolized by alcohol dehydrogenase and aldehyde dehydrogenase, with toxicity likely mediated by the resulting metabolites. Fomepizole, an alcohol dehydrogenase inhibitor, is used to prevent metabolite formation with other toxic alcohol exposures. Fomepizole is recommended for DEG poisoning, though supporting clinical evidence is limited. CASE REPORT: A 31-year-old man presented after ingestion of DEG-containing brake fluid and hydrocarbon-containing "octane booster." He was noted to be clinically intoxicated, with a mildly elevated anion gap metabolic acidosis and no osmolar gap. DEG level was later found to be elevated, consistent with his ingestion. He was treated with fomepizole alone, with resolution of metabolic acidosis and clinical findings over the next 2 days. No delayed neurologic sequelae were present at 52-day follow-up. Our case provides additional evidence supporting the use of fomepizole for DEG poisoning. Consistent with other toxic alcohols, DEG poisoning, especially early presentations, may benefit from empiric fomepizole administration. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: DEG poisoning is potentially life threatening, but treatable if identified early. An ingestion can be toxic despite a normal osmolar gap, leading to false reassurance. Finally, it is rare, so emergency physicians must be made aware of its potential dangers.