False-positive ethylene glycol levels in patients with diabetic ketoacidosis

Endocr Pract. Sep-Oct 1998;4(5):272-3. doi: 10.4158/EP.4.5.272.

Abstract

Objective: To describe two patients with diabetic ketoacidosis and positive ethylene glycol levels and to call attention to the possibility of a false-positive ethylene glycol determination in patients with ketoacidosis.

Methods: Clinical manifestations and laboratory tests in the two patients were summarized. Serum specimens for both patients were analyzed for ethylene glycol, serum ketones, glucose, osmolality, pH, and electrolytes.

Results: Respective laboratory findings in our two patients were as follows: serum glucose levels, 56.4 and 45.7 mmol/L; serum acetone, positive in 1:80 and 1:128 dilution; serum osmolality, 366 and 377 mmol/kg; pH, 6.9 and 7.2; and ethylene glycol, 3.46 and 2.45 mmol/L.

Conclusion: Neither of these two elderly women had ingested ethylene glycol; nevertheless, both had positive results for ethylene glycol on a blood toxicology screen. Review of the literature demonstrates that false-positive ethylene glycol levels can be detected in patients with ketoacidosis. This information is documented in this report and should alert practicing physicians to such a possibility.