What surrogate marker best correlates the glycolate concentration in ethylene glycol poisoned patients?
Anion gap. In a recent systematic review by Roberts DM et al., the anion gap was the surrogate marker that best correlated with the glycolate concentration. The anion gap outperformed other acid-based markers such as pH, base excess and HCO3-. The authors estimate that each mmol of glycolate decreases the HCO3- and increases the anion gap by 1 mmol/L.
Roberts DM et al. The serum glycolate concentrations: its prognostic value and its correlation to surrogate markers in ethylene glycol exposures. Clin Tox Published online 24 March 2022. doi/full/10.1080/15563650.2022.2049811