Glycols (Ethylene and Propylene)

Label Mnemonic:	GLYCOL
Epic code:	LAB615
Downtime form:	A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery

Chemistry
6240 RCP
356-3527

Specimen(s):

Plasma

Collection Medium:

Plasma Separator Tube 4.5 mL

Alternate Collection Media:

Call laboratory for additional acceptable specimen collection containers.

Minimum:

3 mL whole blood from light green top tube or TWO Microtainer^® devices for pediatric patients

Rejection Criteria:

Medico-legal specimens are not accepted.

Testing Schedule:

This test is not run routinely and requires approval of Clinical Pathology Resident on-call (pager #3724 M-F 08:00-17:00; pager #3404 all other times).

Turn Around Time:

4 hours (upon receipt in laboratory)

Reference Range:

Negative (< 10 mg/dL)

Propylene glycol toxicity range not well defined but clinical toxicity more likely if plasma concentration exceed 100 mg/dL.

Critical values:
Ethylene glycol 20 mg/dL or greater
Propylene glycol 100 mg/dL or greater

Comments:

Note that the "Ethylene Glycol, Rapid Assay" (LAB7453) provides more rapid determination of ethylene glycol plasma concentrations. The "Ethylene Glycol, Rapid Assay" test is reflexively ordered if the unexplained osmolar gap is greater than 15 and may also be directly ordered in cases of suspected ethylene glycol ingestion or for monitoring ethylene glycol plasma concentrations in patients receiving treatment for ethylene glycol ingestion.

The glycols by gas chromatography tests may be ordered if there is an interference with the "Ethylene Glycol, Rapid Assay" test or if quantitation of propylene glycol is needed. This procedure individually quantitates ethylene glycol and propylene glycol. Ethylene glycol is commonly found in many automobile antifreezes. Propylene glycol is found in some intravenous drug formulations as a solvent/diluent (e.g., diazepam, lorazepam, etomidate, and phenytoin) and is also found in a small number of automobile antifreezes (e.g., Sierra).

References:
(1) Wilson KC, Reardon C, Theodore AC, and Farber HW.  Propylene 
    glycol toxicity: a severe iatrogenic illness in ICU patients 
    receiving IV benzodiazepines: a case series and prospective, 
    observation pilot study.  Chest 128: 1674-1681, 2005.

(2) Eder AF et al.  Ethylene glycol poisoning: toxicokinetic and
    analytical factors affecting laboratory diagnosis.  Clin Chem 
    44: 168-177, 1998.

(3) Juenke JM et al. Rapid and specific quantification of ethylene
    glycol levels: adaptation of a commercial enzymatic assay to
    automated chemistry analyzers. Am J Clin Pathol 136: 318-324, 
    2011.

(3) Lynd LD et al. An evaluation of the osmole gap as a screening 
    test for toxic alcohol poisoning. BMC Emerg Med 8: 5, 2008. 

Profile result codes:  GLYC, PGLY

Methodology:

Gas Chromatography

CPT Code:

80320

See Additional Information:
Osmolality Gap Calculator
Osmolality Gap - Calculation and Interpretation
Chemistry Critical Lab Values