Ethylene glycol ingestion treated only with fomepizole

Extracorporeal treatment for ethylene glycol poisoning: systematic review and recommendations from the EXTRIP workgroup

Ethylene glycol (EG) is metabolized into glycolate and oxalate and may cause metabolic acidemia, neurotoxicity, acute kidney injury (AKI), and death. Historically, treatment of EG toxicity included supportive care, correction of acid-base disturbances and antidotes (ethanol or fomepizole), and extracorporeal treatments (ECTRs), such as hemodialysis. With the wider availability of fomepizole, the indications for ECTRs in EG poisoning are debated. We conducted systematic reviews of the literature following published EXTRIP methods to determine the utility of ECTRs in the management of EG toxicity. The quality of the evidence and the strength of recommendations, either strong ("we recommend") or weak/conditional ("we suggest"), were graded according to the GRADE approach. A total of 226 articles met inclusion criteria. EG was assessed as dialyzable by intermittent hemodialysis (level of evidence = B) as was glycolate (Level of evidence = C). Clinical data were available for analysis on 446 patients, in whom overall mortality was 18.7%. In the subgroup of patients with a glycolate concentration ≤ 12 mmol/L (or anion gap ≤ 28 mmol/L), mortality was 3.6%; in this subgroup, outcomes in patients receiving ECTR were not better than in those who did not receive ECTR. The EXTRIP workgroup made the following recommendations for the use of ECTR in addition to supportive care over supportive care alone in the management of EG poisoning (very low quality of evidence for all recommendations): i) Suggest ECTR if fomepizole is used and EG concentration > 50 mmol/L OR osmol gap > 50; or ii) Recommend ECTR if ethanol is used and EG concentration > 50 mmol/L OR osmol gap > 50; or iii) Recommend ECTR if glycolate concentration is > 12 mmol/L or anion gap > 27 mmol/L; or iv) Suggest ECTR if glycolate concentration 8-12 mmol/L or anion gap 23-27 mmol/L; or v) Recommend ECTR if there are severe clinical features (coma, seizures, or AKI). In most settings, the workgroup recommends using intermittent hemodialysis over other ECTRs. If intermittent hemodialysis is not available, CKRT is recommended over other types of ECTR. Cessation of ECTR is recommended once the anion gap is < 18 mmol/L or suggested if EG concentration is < 4 mmol/L. The dosage of antidotes (fomepizole or ethanol) needs to be adjusted during ECTR.

High risk and low prevalence diseases: Toxic alcohol ingestion

INTRODUCTION

Toxic alcohol ingestion is a rare but serious condition that carries with it a high rate of morbidity and mortality.

OBJECTIVE

This review highlights the pearls and pitfalls of toxic alcohol ingestion, including presentation, diagnosis, and management in the emergency department (ED) based on current evidence.

DISCUSSION

Toxic alcohols include ethylene glycol, methanol, isopropyl alcohol, propylene glycol, and diethylene glycol. These substances can be found in several settings including hospitals, hardware stores, and the household, and ingestion can be accidental or intentional. Toxic alcohol ingestion presents with various degrees of inebriation, acidemia, and end-organ damage depending on the substance. Timely diagnosis is critical to prevent irreversible organ damage or death and is based primarily on clinical history and consideration of this entity. Laboratory evidence of toxic alcohol ingestion includes worsening osmolar gap or anion-gap acidemia and end organ injury. Treatment depends on the ingestion and severity of illness but includes alcohol dehydrogenase blockade with fomepizole or ethanol and special considerations for the initiation of hemodialysis.

CONCLUSIONS

An understanding of toxic alcohol ingestion can assist emergency clinicians in diagnosing and managing this potentially deadly disease.

Treating ethylene glycol poisoning with alcohol dehydrogenase inhibition, but without extracorporeal treatments: a systematic review

CONTEXT

Ethylene glycol is metabolized to toxic metabolites that cause acute kidney injury, metabolic acidemia, and death. The treatment of patients with ethylene glycol poisoning includes competitively inhibiting alcohol dehydrogenase with ethanol or fomepizole to prevent the formation of toxic metabolites, and extracorporeal treatments such as hemodialysis to remove ethylene glycol and its metabolites. In the absence of significant metabolic acidemia or kidney injury, it is hypothesized that extracorporeal treatments may be obviated without adverse outcomes to the patient if alcohol dehydrogenase inhibitors are used.

OBJECTIVES

The objectives of this study are to: (1) identify indicators predicting ADH inhibitor failure in patients with ethylene glycol poisoning treated with either ethanol or fomepizole for whom extracorporeal treatment was not performed (aside from rescue therapy, see below) (prognostic study), and (2) validate if the anion gap, shown in a previous study to be the best surrogate for the glycolate concentration, is associated with acute kidney injury and mortality (anion gap study).

METHODS

We conducted a systematic review to identify all reported patients with ethylene glycol poisoning treated without extracorporeal treatments but with either fomepizole (fomepizole monotherapy) or ethanol (ethanol monotherapy). Analyses were performed using both one case per patient and all cases (if multiple events were reported for a single patient). Data were compiled regarding poisoning, biochemistry, and outcomes. Treatment failure was defined as mortality, worsening of acid-base status, extracorporeal treatments used as rescue, or a worsening of kidney or neurological function after alcohol dehydrogenase inhibition was initiated. Also, we performed an analysis of previously described anion gap thresholds to determine if they were associated with outcomes such as acute kidney injury and mortality.

RESULTS

Of 115 publications identified, 96 contained case-level data. A total of 180 cases were identified with ethanol monotherapy, and 231 with fomepizole monotherapy. Therapy failure was noted mostly when marked acidemia and/or acute kidney injury were present prior to therapy, although there were cases of failed ethanol monotherapy with minimal acidemia (suggesting that ethanol dosing and/or monitoring may not have been optimal). Ethylene glycol dose and ethylene glycol concentration were predictive of monotherapy failure for ethanol, but not for fomepizole. In the anion gap study (207 cases), death and progression of acute kidney injury were almost nonexistent when the anion gap was less than 24 mmol/L and mostly observed when the anion gap was greater than 28 mmol/L.

CONCLUSION

This review suggests that in patients with minimal metabolic acidemia (anion gap <28 mmol/L), fomepizole monotherapy without extracorporeal treatments is safe and effective regardless of the ethylene glycol concentration. Treatment failures were observed with ethanol monotherapy which may relate to transient subtherapeutic ethanol concentrations or very high ethylene glycol concentrations. The results are limited by the retrospective nature of the case reports and series reviewed in this study and require prospective validation.

Outcomes of death and prolonged renal insufficiency in ethylene glycol poisoned patients

BACKGROUND

Despite the severity of ethylene glycol intoxication, there is a paucity of studies that analyze prognostic factors. This study aims to determine prognostic factors with impact on core outcomes like death and prolonged kidney injury (KI) in ethylene glycol poisoned patients.

METHODS

We retrospectively assessed prevalence, clinical and biochemical features in one large data set from two regional hospitals from the North-East region of Romania, between January 2012 and October 2017. Secondly, we compared prognostic factors of cases treated with dialysis plus antidote (N = 28 patients) with cases who received antidote only and supportive therapy (N = 28 patients).

RESULTS

Of the 56 cases included, 16 deaths (28.57%) were recorded. The symptomatology at admission was more severe among patients requiring hemodialysis: a lower mean value for initial pH, lower initial alkaline reserve (AR) and higher mean values for initial serum creatinine (Cr1). The data analysis (survivors/deceased) showed a correlation between pH, Glasgow Coma Score (GCS), and increased mortality. In addition, we found a correlation between initial mean values for pH, AR (mmol/L), Cr1 (mg/dL), and peak Cr24 (mg/dL) with outcomes of RI or death.

CONCLUSIONS

Compared with survivors, patients who died or had prolonged kidney injury were more likely to exhibit clinical signs such as coma, seizures, and acidosis. Hemodialysis and antidote should be started early and continued until acidosis is corrected.

Treatment of Ethylene Glycol Poisoning with Oral Ethyl Alcohol

Ethylene glycol poisoning is not uncommon in India. The ill effects are primarily caused by its toxic metabolites: glycolic acid and oxalic acid. A 70-year-old female presented to our hospital with ataxia after ingestion of ethylene glycol. The reported case describes the management of ethylene glycol poisoning using oral ethyl alcohol as an alternative to the recommended intravenous ethyl alcohol and fomepizole that are not available for use in India. The need for high degree of clinical suspicion, targeted investigations, and early instigation of treatment is of prime importance in cases of ethylene glycol poisoning as it can lead to long-term complications or even death.

Lactate Gap: A Diagnostic Support in Severe Metabolic Acidosis of Unknown Origin

Ethylene glycol poisoning is a medical emergency. The metabolites glycolate and glyoxylate give metabolic acidosis. Because of similar structure, these metabolites are misinterpreted as lactate by many point-of-care blood gas analyzers. The falsely high lactate values can lead to misdiagnosis, inappropriate laparotomies, and delayed antidotal therapy. As laboratory analyzers measure plasma lactate only, the difference or the “lactate gap” aids in early diagnosis. We present a patient with severe metabolic acidosis and elevated lactate levels on the point-of-care analyzer. A lactate gap supported the diagnosis of ethylene glycol poisoning. Hemodialysis and fomepizole treatment could be started immediately.

Toxic alcohol diagnosis and management: an emergency medicine review

Toxic alcohols are a group of substances containing a hydroxyl group not meant to be ingested. They are the cause of a significant number of accidental and non-accidental exposures. Toxic alcohol poisoning can be associated with a significant degree of morbidity and mortality if not promptly recognized and treated. This review describes the clinical presentation and an approach to the recognition and management for toxic alcohol poisoning. Toxic alcohols classically refer to a group of alcohols not meant for ingestion. Methanol, ethylene glycol, and isopropyl alcohol are readily available in common hardware and household materials. Toxic alcohols are ingested for a variety of reasons including accidental exposures, intentional inebriation, homicide and suicide. The patient with an altered mental status or concerning history warrants consideration of this potentially deadly ingestion. Treatment considerations include alcohol dehydrogenase blockade and hemodialysis. Toxic alcohol poisoning can be an elusive diagnosis. This review evaluates toxic alcohol poisoning signs and symptoms and an approach to diagnosis and management.

Ethylene Glycol, Hazardous Substance in the Household

Ethylene glycol is a colorless, odorless, sweet-tasting but poisonous type of alcohol found in many household products. The major use of ethylene glycol is as an antifreeze in, for example, automobiles, in air conditioning systems, in de-icing fluid for windshields, and else. People sometimes drink ethylene glycol mistakenly or on purpose as a substitute for alcohol. Ethylene glycol is toxic, and its drinking should be considered a medical emergency. The major danger from ethylene glycol is following ingestion. Due to its sweet taste, peoples and occasionally animals will sometimes consume large quantities of it if given access to antifreeze. While ethylene glycol itself has a relatively low degree of toxicity, its metabolites are responsible for extensive cellular damage to various tissues, especially the kidneys. This injury is caused by the metabolites, glycolic and oxalic acid and their respective salts, through crystal formation and possibly other mechanisms. Toxic metabolites of ethylene glycol can damage the brain, liver, kidneys, and lungs. The poisoning causes disturbances in the metabolism pathways, including metabolic acidosis. The disturbances may be severe enough to cause profound shock, organ failure, and death. Ethylene glycol is a common poisoning requiring antidotal treatment.

Five-year review of a UK 24 hour testing service for plasma ethylene glycol and diethylene glycol

Background

We present a 5-year review of our UK service for plasma ethylene glycol and diethylene glycol determination in cases of acute poisoning.

Methods

Ethylene glycol and diethylene glycol have been measured on all samples received for screening for toxicity by gas chromatography-flame ionization detection over a five-year period. A detailed audit of the results has been undertaken.

Results

In this period, we received 811 requests, 56% were for first-time screening and 44% repeat analysis where a positive sample has already been received. Of the first-time screen samples, 33.5% screened positive for glycol poisoning. The mean positive ethylene glycol concentration was 1204 mg/L (range 31 to 8666 mg/L). Diethylene glycol was present in 14% of ethylene glycol positive samples but never found alone.

Conclusions

The data presented here suggest it is not essential to measure diethylene glycol since its inclusion is rarely likely to change patient management.

Green protection of pyrazole, thermal isomerization and deprotection of tetrahydropyranylpyrazoles, and high-yield, one-pot synthesis of 3(5)-alkylpyrazoles

3(5)-Alkylpyrazoles are obtained in high yield from pyrazole by a one-pot procedure.

Methanol and ethylene glycol intoxication

Accidental or intentional ingestion of substances containing methanol and ethylene glycol can result in death, and some survivors are left with blindness, renal dysfunction, and chronic brain injury. However, even in large ingestions, a favorable outcome is possible if the patient arrives at the hospital early enough and the poisoning is identified and appropriately treated in a timely manner. This review covers the common circumstances of exposure, the involved toxic mechanisms, and the clinical manifestations, laboratory findings, and treatment of methanol and ethylene glycol intoxication.

A systematic review of ethanol and fomepizole use in toxic alcohol ingestions

Objectives. The optimal antidote for the treatment of ethylene glycol or methanol intoxication is not known. The objective of this systematic review is to describe all available data on the use of ethanol and fomepizole for methanol and ethylene glycol intoxication. Data Source. A systematic search of MEDLINE and EMBASE was conducted. Study Selection. Published studies involving the use of ethanol or fomepizole, or both, in adults who presented within 72 hours of toxic alcohol ingestion were included. Our search yielded a total of 145 studies for our analysis. There were no randomized controlled trials, and no head-to-head trials. Data Extraction. Variables were evaluated for all publications by one independent author using a standardized data collection form. Data Synthesis. 897 patients with toxic alcohol ingestion were identified. 720 (80.3%) were treated with ethanol (505 Me, 215 EG), 146 (16.3%) with fomepizole (81 Me, 65 EG), and 33 (3.7%) with both antidotes (18 Me, 15 EG). Mortality in patients treated with ethanol was 21.8% for Me and 18.1% for EG. In those administered fomepizole, mortality was 17.1% for Me and 4.1% for EG. Adverse events were uncommon. Conclusion. The data supporting the use of one antidote is inconclusive. Further investigation is warranted.

Ethylene glycol poisoning: quintessential clinical toxicology; analytical conundrum

Ethylene glycol poisoning is a medical emergency that presents challenges both for clinicians and clinical laboratories. Untreated, it may cause morbidly or death, but effective therapy is available, if administered timely. However, the diagnosis of ethylene glycol poisoning is not always straightforward. Thus, measurement of serum ethylene glycol, and ideally glycolic acid, its major toxic metabolite in serum, is definitive. Yet measurement of these structurally rather simple compounds is but simple. This review encompasses an assessment of analytical methods for the analytes relevant for the diagnosis and prognosis of ethylene glycol poisoning and of the role of the ethylene glycol metabolites, glycolic and oxalic acids, in its toxicity.

Massive ethylene glycol ingestion treated with fomepizole alone-a viable therapeutic option

Fomepizole is used to treat and prevent toxicity from ethylene glycol poisoning. Treatment with fomepizole without hemodialysis in massive ethylene glycol ingestion has been rarely reported in the literature; however, published literature and practice guidelines recommend considering dialysis for ethylene glycol levels >50 mg/dL. We report a case of massive ethylene glycol ingestion resulting in the highest serum ethylene glycol concentration in a patient without ethanol co-ingestion who was treated with fomepizole and was not hemodialyzed. A 48-year-old male presented to the emergency department after reportedly ingesting >1 liter of antifreeze in an attempt at self-harm. He denied concomitant ethanol consumption. His initial presenting serum ethylene glycol level was 700 mg/dL, with normal renal function, and a metabolic acidosis with a high anion gap. One hour after presentation, he was started on intravenous fomepizole. Treatment with fomepizole continued until the patient's plasma ethylene glycol concentration was 16 mg/dL. His metabolic acidosis quickly resolved, he had no adverse reactions to the treatment, and his renal function remained normal. Ultimately, he was discharged to a psychiatric unit without sequelae. Published literature and practice guidelines suggests considering hemodialysis initiation in patients with an ethylene glycol level > 50 mg/dL. This recommendation is anecdotally, rather than evidence, based. With the potential risks inherent in hemodialysis, our case provides evidence that treatment with fomepizole without hemodialysis appears to be a viable alternative option in patients with even extremely high plasma ethylene glycol concentrations as long as their renal function is intact.

Hyperoxaluria after ethylene glycol poisoning

Treatment of otherwise lethal ethylene glycol poisoning depends on rapid diagnosis, aggressive supportive care, appropriate use of alcohol dehydrogenase inhibitors and, in selected patients, hemodialysis. Next to that, specific measures to prevent renal or systemic calcium-oxalate deposition are important. We report the case of a 12-year-old girl who ingested more than five times the lethal dosis of ethylene glycol in a suicide attempt. At admission her serum ethylene glycol concentration was 88 mg/dl. Under treatment by ethanol infusions to block the alcohol dehydrogenase and by hemodialysis to eliminate ethylene glycol and its toxic metabolites, this level decreased to below 15 mg/dl within 36 h. The plasma oxalate level, however, rose to a maximum of 89 micromol/l (normal <6.3 +/- 1.1) on day 3 and only normalized on day 7 after ingestion. In addition, urinary oxalate excretion was elevated (maximum 1.16 mmol/1.73 m(2)/24 h). Both lead to calcium-oxalate oversaturation and hence to the risk of local (renal) or systemic crystal deposition. Therefore, alkaline citrate was given as a preventive measure to increase urinary oxalate solubility, but nephrocalcinosis still developed. Metabolic acidosis, hypocalcaemia, and neurological symptoms had not occurred. Four weeks after discharge, both plasma and urinary oxalate levels were normal.