Delayed fomepizole initiation after massive ethylene glycol ingestion: a case report of survival with dialysis support

Abstract

Ethylene glycol poisoning is a rare but life-threatening intoxication. Early diagnosis is often difficult, as the initial presentation resembles ethanol intoxication, while later stages are characterized by severe high–anion gap metabolic acidosis. Diagnostic challenges are compounded by the fact that glycolic acid, a toxic metabolite of ethylene glycol, may be falsely detected as lactate by blood gas analyzers.

We report a 25-year-old man who ingested 500 mL of automobile antifreeze along with 10 fluoxetine tablets in a suicide attempt. He presented with dizziness, abdominal pain, agitation, and rapidly progressed to coma (Glasgow Coma Scale score 6). Laboratory tests showed severe metabolic acidosis (pH 7.09, HCO₃⁻ 3.2 mEq/L, anion gap 22.5 mEq/L), osmotic gap 83 mOsm/L, hyperlactatemia, hyperglycemia, mild hypocalcemia, and urinary calcium oxalate crystals. Immediate management included intravenous bicarbonate and calcium gluconate. Continuous hemofiltration was started shortly after admission to the intensive care unit, followed by conventional hemodialysis the next day. Since fomepizole was not available, ethanol was administered via nasogastric tube as an alternative antidote until fomepizole could be procured more than 20 hours after admission. Despite delayed antidotal therapy, the patient’s metabolic status improved and he was extubated on day 5. However, he developed acute kidney injury with persistent anuria, requiring ongoing dialysis. On day 8, he was transferred to his home country for continuation of renal replacement therapy.

This case demonstrates the importance of early recognition of ethylene glycol poisoning through the combined assessment of anion and osmotic gaps. When fomepizole is not immediately available, ethanol remains a reliable substitute to delay toxic metabolism. Prompt initiation of supportive therapy and dialysis is crucial for survival, even in cases with delayed presentation and massive ingestion.