Hello,
Ethylene glycol is an alcohol that is used as an automotive antifreeze. The toxicity form ethylene glycol ingestion is due to its metabolic end products which result in acidosis and the formation of oxalate crystals that accumulates in the body and excreted in the urine.
Its precipitation in the kidney results in renal insufficiency. Consumption of the blood calcium results in hypocalcemia. The main effects of ethylene glycol intoxication are on the CNS and the kidney.
So patients will have rapid deep breathing, altered mental status. Renal damage causes oliguria (decline in the 24 hours urine amount) and increased levels of
creatinine and
urea. Urinary excretion of calcium is high and blood level of calcium is low. Hypocalcemia results in abnormal muscle contraction, altered conscious level and cardiac
arrhythmias.
Essential investigations include, ethylene glycol level, calcium level in urine and blood, arterial blood gases, blood Na,
blood Glucose,
creatinine,
urea, blood osmolality (amount of solute in a liter of body fluids) and urine analysis. When blood solutes increase (in this case ethylene glycol) the osmolality and the osmolal gap increase.
Diagnosis is primarily based on a history of exposure or suspicious exposure to ethylene glycol intoxication confirmed by the presence of any of the following 3 findings:
1- The blood level of ethylene glycol is 20 mg/dL or more.
2- Ethylene glycol ingestion is confirmed in the presence of an osmolal gap of >10 mOsm/L.
3- Suspicion of ethylene glycol intoxication with 2 of the following findings that suggest either acidosis or excess blood solutes, or excess calcium in urine as follows:
I. Arterial pH level < 7.3 (acidosis).
II. NaHCO3 < 20 mg/dL.
III. Osmol gap > 10 mOsm/L.
IV. Urinary oxalate crystals.
Postmortem evidence of changes in the body organs like brain edema and acute renal tubular necrosis are indicative of ethylene glycol intoxication. Oxalate crystals are usually found in these organs and support also the diagnosis. Ethylene glycol concentration can be measured in different tissues and body fluids.
Hope you find this information useful.
Best regards.
This answer does not substitute for direct medical consultation.
Dr. Safaa Mahmoud.
MB BCh, MSc Internal Medicine. MD Medical Oncology.
PhD Experimental Medicine and Biochemical Science.