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'Calcium Oxalate Crystals in Ethylene Glycol Toxicity'

'An 80-year-old man with a remote history of alcohol-use disorder presented to the emergency department with altered mental status after a fall at home. He was somnolent and unable to provide any further history...'

‘The patient later reported that he had unintentionally ingested antifreeze.’

['Calcium Oxalate Crystals in Ethylene Glycol Toxicity'](


Random, this is Car Talk, not the Dumb things people do site.

It is car related though.

Fortunately the antidote to antifreeze ingestion is fun. High-proof alcohol. Bottoms up!

‘Lessons Learned From Yet Another Episode of Diethylene Glycol Poisoning: It Happened Before and It Happened Again’

'If DEG poisoning is suspected, inhibition of its metabolism by inhibiting alcohol dehydrogenase enzymes is a logical treatment and has been shown to be effective in the rat model. Fomepizole is the preferred antidote for this purpose, although in situations where it is not available ethanol could be used.'

The lesson for the Car Talk community: keep the antifreeze away from grandpa.

My “take-home”: after working on the cooling system of my vehicle, have several beers, just to be pro-active, mind you! (Or in med-speak, "Oral application of a 5% EtOH solution in a prophylactic manner.’)


Seriously this is why coolant must be stored and disposed of properly. Children and animals are attracted to the smell and taste of ethylene glycol.

It was used to sweeten medicines in the '30s, to sweeten toothpaste and similar stuff in China recently (the reason for that second article from Archives of Internal Medicine). There are ‘safe’ anti-freezes that have a bittering agent added.

The physicians looked for an alternative treatment for DEG poisoning when they figured out that rummies were drinking just enough to get a diagnosis and alcohol ‘treatment’.

Heard about dogs and cats licking the stuff up but never thought someone would drink it. Here’s how I do cooling system repairs now: “Dave, can you get me in sometime to change my antifreeze?”

There are also safe anitfreezes that use propylene glycol instead of ethylene glycol. PG is safe enough that it’s used as food ingredients. And you will find it in RV water system antifreeze, as you don’t want someone to incompletely flush the system in the spring and then end up with poison in the water tank.

Don’t freak out if your urine contains CaOx crystals, they are common. But when the rest of the labs and patient history are reviewed you get a different picture. Our ‘people’ lab also received veterinary specimens. Ethylene glycol is usually a death sentence for animals.
Full write up of OP post.

An 80-year-old man with a remote history of alcohol-use disorder presented to the emergency department with altered mental status after a fall at home. He was somnolent and unable to provide any further history. Serum studies revealed a creatinine level of 2.4 mg per deciliter (212 μmol per liter; reference range, 0.6 to 1.3 mg per deciliter [53 to 115 μmol per liter]), a bicarbonate level of 9 mmol per liter (reference range, 21 to 32), an anion gap of 26 mmol per liter (reference range, 7 to 16), and a serum osmolality of 357 mOsm per kilogram of water (reference range 275 to 295), with an osmolal gap of 49 mOsm per kilogram of water (reference range, <10). Examination of urine sediment by means of light microscopy revealed calcium oxalate monohydrate crystals with two different morphologic features: narrow rectangles with pointed ends (Panel A, arrows) and dumbbell-shaped crystals (Panel B). Under polarized light, the crystals were positively birefringent; crystals were blue when parallel to the light and yellow when perpendicular to the light (Panel C). Given the high clinical probability of ethylene glycol toxicity, blood was drawn for measurement of the ethylene glycol level, and treatment with fomepizole and dialysis were initiated immediately. Ethylene glycol poisoning most commonly occurs after the ingestion of antifreeze or deicing solution. The patient’s ethylene glycol level, which became available 40 hours after the serum was drawn, was 211 mg per deciliter (34 mmol per liter; reference range, <1 mg per deciliter [<0.2 mmol per liter]). His mental status and renal function normalized after treatment with fomepizole for 3 days and four hemodialysis sessions over 5 days. The patient later reported that he had unintentionally ingested antifreeze.

As I said ethylene glycol coolants must be stored and disposed of safely. Do not drain it into the street.

Check with your local waste water treatment plant, I was told it is fine to dump coolant, antifreeze, whatever your terminology into the toilet as the bugs that clean stuff at the treatment plant love it. Check with a septic service if you are on a holding tank or septic service. Evidently a waste water treatment plant will spend much time with aeration, temperature and environment to keep the digesting bugs happy.
Note the catch basin or street drainage drain for rain in the street is probably not connected to the sanitary sewer system so that is not a good place to dump stuff.
Just to go green, our wwtp plant collects the methane produced in the digesters, filters it and uses it to maintain the happy temp for the bugs and also dry solids for lees crap going to the landfill! Great stuff!

That is exactly how I do it except it is “Steve”.

‘Our patient, a 62-year-old man with a history of depression, presented to an emergency department 5 hours after ingesting antifreeze (Fleet Charge SCA Precharged Coolant/Antifreeze [Peak]).’

Ever stop at a rest stop on a freeway in Nebraska (or many other states up that way)? They have warnings against giving the water to babies because of the danger of methemoglobinemia (a methyl group attaching itself to your hemoglobin).