Ethylene glycol toxicity

Metabolic acidosis with a high anion gap and high osmolar gap is seen in ethylene glycol poisoning

Ethylene glycol is a type of alcohol used as a coolant or antifreeze

Features of toxicity are divided into 3 stages:

• Stage 1: symptoms similar to alcohol intoxication: confusion, slurred speech, dizziness
• Stage 2: metabolic acidosis with high anion gap and high osmolar gap. Also tachycardia, hypertension
• Stage 3: acute kidney injury

Management has changed in recent times

• ethanol has been used for many years
• works by competing with ethylene glycol for the enzyme alcohol dehydrogenase
• this limits the formation of toxic metabolites (e.g. glycoaldehyde and glycolic acid) which are responsible for the haemodynamic/metabolic features of poisoning
• fomepizole, an inhibitor of alcohol dehydrogenase, is now used first-line in preference to ethanol
• haemodialysis also has a role in refractory cases