What is Ethylene Glycol Toxicity?
Ethylene glycol (C2H6O2) is a harmful alcohol found in various everyday household and industrial items. When we talk about “toxic alcohols”, we are generally referring to substances like methanol, ethylene glycol, and isopropyl alcohol. Exposure to ethylene glycol can be extremely dangerous, potentially leading to serious health issues or even death if untreated.
Ethylene glycol is a clear, sweet-tasting liquid that is most commonly found in antifreeze, but it’s also occasionally used for other things like industrial solvents. It can cause harm if someone accidentally or deliberately swallows it, and its sweetness often leads to accidental poisonings. Some people might intentionally ingest it in a suicide attempt or as a substitute for alcohol if regular alcohol is not available.
The level of harm ethylene glycol can cause varies and the way it’s handled usually involves supportive care, closely watching for changes in the person’s condition through lab tests, and treatment with an antidote. The main treatments are either ethanol or fomepizole, and sometimes kidney dialysis (a process that removes waste and excess water from the blood as a substitute for normal kidney function) might be needed.
What Causes Ethylene Glycol Toxicity?
Ethylene glycol poisoning typically occurs when someone swallows it. In contrast to other types of alcohol like methanol, it does not easily get into the body through the skin. Most of the time, people ingest it on purpose, either as suicide attempts or occasionally to get drunk. Children can also accidentally consume a harmful amount because it has a sweet taste, which they might find when exploring their surroundings.
Risk Factors and Frequency for Ethylene Glycol Toxicity
There are certain groups of people who are at greater risk of encountering ethylene glycol, a toxic substance. These include toddlers and young children who are curious about their surroundings, people with an alcohol problem, and individuals who may be feeling suicidal.
- Toddlers and young children exploring their environment are at risk.
- Those with alcohol use disorder are another risk group.
- Suicidal individuals may also come into contact with ethylene glycol.
- According to data from the American Association of Poison Control Centers, there were 6,374 cases involving ethylene glycol in 2016.
- Most of these cases involved adults over 20 and were done on purpose.
- Out of these, 686 cases involved children under 12 years, with 13 cases of unknown child age.
Signs and Symptoms of Ethylene Glycol Toxicity
Identifying and diagnosing cases of self-harm or substance abuse can be challenging, as patients may feel embarrassed or unwilling to share the details of their situation. They might also downplay the severity of what they swallowed. On the other hand, accidental cases of substance ingestion are usually reported or witnessed, removing the guesswork. In certain instances, doctors have to deduce if the patient’s symptoms, like an abnormally high acidity in the blood or potential kidney damage, are due to harmful substances.
The seriousness of the condition can vary based on several factors – the time gap between exposure and medical attention, whether other substances like ethanol were consumed simultaneously, or the availability of early treatment. Toxicity from ethylene glycol, a harmful substance, usually begins with symptoms similar to drunkenness, potentially progressing to a state of reduced brain function. At this initial stage, there’s often an imbalance in blood osmolarity – how many chemicals the blood contains – with no abnormalities in anions or acid levels. The situation changes as the substance is metabolized and its by-products build up in the body, increasing the anion gap and leading to a condition of high acidity in the body.
As the harmful substance continues to break down in the body over a 4 to 12 hour period, the patient’s condition may worsen, and they may feel unwell with decreased brain function. The body may attempt to compensate by increasing breathing or heartbeat. However, after around 12 hours, kidney damage may also be evident by elevated levels of creatinine, a waste product, in the blood. This damage occurs due to calcium oxalate crystals clogging the kidney tubules and can lead to hypocalcemia – dangerously low levels of calcium in the body. This can put the patient at risk of muscle cramps, seizures, heart rhythm disorders, and the prolongation of the QT interval, a specific measure on an electrocardiogram.
- Increased brain function reduction
- Increased breathing or heart rate
- Evidence of kidney damage by elevated levels of creatinine
- Risk of muscle cramps, seizures, heart rhythm disorders, and QT interval prolongation due to hypocalcemia
Between 12 and 18 hours after exposure, the patient may start producing a reduced volume of urine. At this point, if treated in time, the kidney damage can usually be reversed, and dialysis may not be necessary. However, with greater delays in treatment, the condition may worsen and lead to acute kidney failure and widespread disease, potentially affecting the lungs, brain, and heart. These serious outcomes, including coma and death, are believed to be linked to the calcium oxalate deposits in the body. Therefore, early treatment is key to save lives.
Testing for Ethylene Glycol Toxicity
If a patient has swallowed ethylene glycol, a harmful substance found in some antifreeze products, their symptoms can range from no noticeable effect to severe damage and illness. The timing and amount swallowed, as well as the patient’s overall health, will influence the response to this toxic substance.
To identify and monitor the effects of ethylene glycol poisoning, doctors may ask for an electrocardiogram, a basic metabolic panel, and acetaminophen concentration tests. If self-harm is suspected, other tests, such as a complete blood count, liver function tests, lipase, pregnancy test, lactate, alcohol, and salicylate levels may also be necessary. The presence of salicylate toxins is particularly important to rule out if the patient shows signs of metabolic acidosis, a harmful condition where the body produces too much acid.
Detecting the exact levels of toxic alcohols in the patient’s body can be tricky. While some hospitals have the needed technology, many do not. Even when available, it can take hours or even days to get the results. This is a problem, as doctors need to make decisions quickly in cases of ethylene glycol poisoning.
Since the test results take time to arrive, doctors use a strategy of watching and waiting. They monitor the patient closely, checking for changes in their symptoms and running tests every 2 to 4 hours. This process is important to identify any increases in anion gap metabolic acidosis. This type of acidosis happens when the body can’t remove enough acid or produce enough bicarbonate, a chemical that helps neutralize acid in the body.
Doctors often use a number called the osmolar gap to estimate the effects of the poisoning. This number indicates the presence of substances like ethylene glycol that affect the body’s chemical balance. It can provide a clue on when to start treatment. However, doctors must interpret it carefully and consider other information, as its level can change during the course of poisoning.
If a patient comes in with symptoms that suggest ethylene glycol toxicity, doctors will also check for signs of kidney damage. Importantly, they have to rule out other possible causes of the patient’s symptoms. If the patient shows signs of acidosis but is otherwise stable, they will often be given fluids to help their body process and remove the poison.
Doctors may also calculate a theoretical level of alcohol (including not only ethanol or drinking alcohol but also other types of alcohol like ethylene glycol) in the bloodstream, based on the amount and type of substance the patient swallowed. While this method has its limits, it can give useful information for cases of small unintentional exposures, which are quite common in children.
Confirmation of ethylene glycol poisoning comes when lab tests detect a certain level of this substance in the blood. However, other signs like changes in the patient’s acid-base balance and symptoms are also crucial. Additional signs of ethylene glycol poisoning may include the presence of certain types of crystals in the urine, abnormal urine fluorescence due to some additives found in antifreeze products, low levels of calcium in the blood, changes in heart rhythm, and elevated levels of lactic acid in the blood.
Treatment Options for Ethylene Glycol Toxicity
There are several treatment options if someone has consumed a harmful chemical known as ethylene glycol. These options include supportive care to manage symptoms, the use of medication, and in severe cases, dialysis – a procedure that filters waste and excess fluid from the blood.
Fomepizole, a medicine, is often used to handle this kind of poisoning. It works by blocking the chemical reactions that allow ethylene glycol to damage the body. Another potential treatment is ethanol, a type of alcohol that can also block these harmful reactions. There are pros and cons to both of these treatments. Fomepizole is easy to give, does not make the patient feel drunk, and blocks the harmful reactions more effectively than ethanol. However, it tends to be quite expensive. Ethanol, on the other hand, is cheaper but harder to manage, can make the patient feel drunk, and needs careful monitoring.
The decision to use one of these treatments depends on the individual’s medical condition. If the ethylene glycol levels in the patient are high enough or if there are signs of severe acid build-up in the body, it is advised to initiate the antidote treatment immediately.
After fomepizole is given, the metabolism process of ethylene glycol can be halted for approximately 12 hours. This provides enough time to measure the ethylene glycol concentration and decide if dialysis is needed.
If Fomepizole isn’t available, ethanol can be used instead. However, it’s trickier to use ethanol as a treatment because it needs to be closely controlled and can make the patient drunk. Despite being cheaper than Fomepizole, the total cost during hospital stays can be higher due to these complexities.
Another important part of the treatment process is filtering out the harmful substances from the patient’s body, a process called dialysis. However, if the patient’s kidneys are still healthy and the other symptoms aren’t too severe, doctors might opt to use fomepizole alone instead of combining it with dialysis, as the latter can increase the risk and cost to the patient.
In addition to these treatments, there are other options that can be employed. For instance, a substance called sodium bicarbonate might help, especially in cases where acid levels are dangerously high. If the patient’s calcium levels drop too low, a substance called calcium gluconate might be helpful. Seizures resulting from low calcium levels can be managed with a type of medication called benzodiazepines. Also, thiamine, pyridoxine, and magnesium may potentially help divert the harmful reactions of ethylene glycol by directing them toward less harmful substances.
Based on seriousness of the symptoms and complexity of the treatment, admission to the intensive care unit may be considered. This is particularly so if dialysis or ethanol treatment is required.
What else can Ethylene Glycol Toxicity be?
If someone has ingested a harmful substance, such as a toxic form of alcohol, doctors would need to consider several possibilities when diagnosing their symptoms. These include:
- Common symptoms due to a harmful substance build-up in the body, known as metabolic acidosis,
- Ingestion of other harmful substances, for example, overdose of painkillers like aspirin or paracetamol, iron, other forms of alcohols, carbon monoxide, and cyanide,
- Presence of more than one harmful or toxic substance in the body,
- Health conditions that aren’t related to toxins such as alcoholic ketoacidosis (a complication from drinking too much alcohol), diabetic ketoacidosis (a severe diabetes complication), sepsis (an overwhelming infection), or uremia (a kidney disease).
It’s essential that doctors review all these potential causes to ensure they make an accurate diagnosis.
What to expect with Ethylene Glycol Toxicity
When a diagnosis is made quickly and treatment is provided promptly, people usually get better. However, if the diagnosis is delayed or not recognized on time, serious health complications or even death can occur.
Possible Complications When Diagnosed with Ethylene Glycol Toxicity
If people manage to overcome ethylene glycol poisoning, there is usually an improvement in any related kidney disease. However, they might still need ongoing kidney treatment and dialysis after they leave the hospital.
Patients usually see an improvement in kidney disease after surviving ethylene glycol poisoning. However, after being discharged from the hospital, they may still need further kidney care and dialysis.
Preventing Ethylene Glycol Toxicity
It’s crucial to store all products containing antifreeze and similar substances in clearly marked containers, and to keep them somewhere children can’t access. This preventive step can help keep your kids safe from accidentally coming into contact with these harmful substances.
