Delayed admission for ethylene glycol poisoning: lack of elevated serum osmol gap.

In the absence of an immediately available serum ethylene glycol (EG) assay, the diagnosis of EG poisoning is usually based on anamnesis, clinical findings and presence of metabolic acidosis with elevated serum anion gap, elevated serum osmol gap, hypocalcemia and crystalluria. We report two cases of EG poisoning, both presenting without an elevated serum osmol gap and we discuss conditions which facilitate such a presentation, especially delayed hospital admission. Finally, we confirm the fact that determination of the osmol gap can fail as a screen for EG poisoning.