Keywords: lactate, lactic acid, ethylene glycol (PubMed Search)
Ethylene glycol can result in elevated lactate concentrations secondary to hypotension and organ failure in severely poisoned patients. However, lactate production by these mechanisms tends to result in serum concentrations less than 5 mmol/L.
Unfortunately, higher lactate levels don't necessarily rule out ethylene glycol. The glycolate metabolite causes a false-positive lactate elevation when measured by some analyzers, particularly with whole blood arterial blood gas analyzers. Specific models implicated include: ABL 625, Radiometer ABL 700, Beckman LX 20, Chiron 865, Bayer (formerly Chiron) 860, Rapidlab (Bayer) 865, Integra and to a lesser extent, Hitachi 911 analyzers, but not the Vitros 950 or Vitros 250.
The degree of lactate elevation directly correlates with the concentration of glycolate present, and the artifact probably results from the lack of specificity of the lactate oxidase enzyme used in these machines.
Woo MY, et al. Artifactual elevation of lactate in ethylene glycol poisoning. J Emerg Med. 2003;25:289-93.
Fijen J, et al. False hyperlactatemia in ethylene glycol poisoning. Intensive Care Med. 2006;32:626-7.
Brindley PG, et al. Falsely elevated point-of-care lactate measurement after ingestion of ethylene glycol. CMAJ. 2007;176:1097-9.
Manini AF, et al. Relationship between serum glycolate and falsely elevated lactate in severe ethylene glycol poisoning. J Anal Toxicol. 2009;33:227-9.
Morgan TJ, et al. Artifactual elevation of measured plasma L-lactate concentration in the presence of glycolate. Crit Care Med. 1999;27:2177-9.
Porter WH, et al. Interference by glycolic acid in the Beckman Synchron method for lactate: a useful clue for unsuspected ethylene glycol intoxication. Clin Chem. 2000;46:874-5.
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