Ethylene glycol poisoning: a rare but life-threatening cause of metabolic acidosis-a single-centre experience

Real-world safety and effectiveness of intravenous fomepizole in patients with ethylene glycol and methanol poisoning in Japan: results of a 7-year post-marketing surveillance study

BACKGROUND

Fomepizole is a competitive alcohol dehydrogenase inhibitor used for the treatment of ethylene glycol and methanol poisoning. We evaluated the safety and effectiveness of fomepizole in patients with ethylene glycol or methanol poisoning in Japan.

RESEARCH DESIGN AND METHODS

This retrospective post-marketing surveillance study conducted in Japan registered patients who received fomepizole intravenous infusion per the package insert (January 2015-June 2022). Endpoints included adverse drug reactions/infections (ADRs), arterial blood pH, and treatment outcomes.

RESULTS

Of 147 patients registered (91 institutions), 131 and 126 were included in the safety and effectiveness analysis sets, respectively. Mean age was 43.6 years, and 66.4% were male. Mean time from poison ingestion to treatment was 15.1 hours; 66.4% received concomitant hemodialysis. No serious ADRs were reported. ADRs were reported in seven patients; the most-reported ADR was vomiting (2.3%). Seven patients died, 105 survived without sequelae, and 19 survived with sequelae. Most common sequelae were renal failure or renal dysfunction. Mean arterial blood pH increased to 7.4 by 4 hours of treatment, remaining stable for 24 hours post-treatment.

CONCLUSIONS

Fomepizole is well tolerated and helps improve clinical outcomes in patients with ethylene glycol or methanol poisoning in Japan.

TRIAL REGISTRATION

Japanese Pharmaceutical Information Center (JapicCTI-152817).

Emerging progressive atypical acute kidney injury in young children linked to ethylene glycol and diethylene glycol intoxication

BACKGROUND

There had been a sudden surge of unusually severe and rapidly progressing acute kidney injury (AKI) incidence in Indonesia since August 2022 which did not correspond to the rise of COVID-19 incidence. We suspected this was related to ethylene glycol (EG) and diethylene glycol (DEG) intoxication. This study is aimed at describing the clinical and laboratory characteristics of AKI related to D(EG) intoxication in order to spread awareness of the possibility of intoxication in cases of rapidly progressing AKI with unknown etiology.

METHODS

We conducted a cross-sectional study by collecting secondary data from the pediatric AKI registry at a national referral hospital in Jakarta, Indonesia. Data on children admitted from January to November 2022 with diagnosis of stage 3 AKI based on KDIGO criteria were included. Data regarding demographics, symptoms prior to anuria, laboratory results, infection panel including COVID-19 status, treatment administered, and mortality were analyzed.

RESULTS

Sixteen patients tested positive for EG and DEG, all with history of consuming syrup-based medications. High anion gap metabolic acidosis was observed in majority of patients with mean pH 7.33 ± 0.07 and mean anion gap 15.6 ± 7.8 mEq/L. No patient had high osmolal gap (mean osmolal gap 3.46 ± 4.68). One deceased patient, who had kidney biopsy performed, showed severe damage and calcium oxalate crystals in the kidney tissue. Mortality was recorded in six patients (37.5%).

CONCLUSION

Careful history taking of patient's clinical course, including consumption of syrup-based medications and laboratory findings, might aid clinicians to establish a working diagnosis of D(EG) intoxication without needing to wait for blood toxicology test. Early diagnosis and therapy are crucial to prevent substantial mortality.

Nephroprotective effect of PHYMIN-22 on ethylene glycol induced urolithiasis rat model

The present study was designed to evaluate the antiurolithiatic effect of PHYMIN-22 against ethylene glycol-induced urolithiasis in rats. Healthy Albino male rats with 200-230 g body weight were randomly divided into five groups, each with 5 animals, control group, EG group (0.75%), PHYMIN-22 treatment group (0.75% EG 14 days and 100 mg/kg PHYMIN-22 next 14 days), PHYMIN-22 drug control group (100 mg/kg) and cystone treatment group (0.75% EG 14 days and 750 mg/kg cystone next 14 days). Biochemical testing was adopted for measuring the blood and urine parameters, as well as the level of antioxidants including superoxide dismutase (SOD), Catalase (Cat), Glutathione peroxidase (GPx) and glutathione (GSH) in kidney tissues. Hematoxylin and eosin (HE) staining was utilized to observe the histopathological changes in the kidney tissue. End of the experiment the PHYMIN-22 treatment reduced the urine and serum calcium (p < 0.01; p < 0.01), oxalate (p < 0.01; p < 0.01), phosphate (p < 0.01; p < 0.01), uric acid (p < 0.001; p < 0.001), protein (p < 0.001; p < 0.001), and creatinine (p < 0.001; p < 0.001) respectively, serum indicators ALT (p < 0.001) and AST (p < 0.001) level and non-enzymic antioxidant GSH (p < 0.001) compared to EG induced urolithiasis animals (Diseased control group). PHYMIN-22 treatment significantly increased urine volume, pH, and body weight, and antioxidants include CAT (p < 0.001; p < 0.001), SOD (p ˃ 0.05; p < 0.05), and GPX (p < 0.01; p < 0.001) compared to Diseased control group animals. The effect of PHYMIN-22 on EG-induced urolithiasis animals could be by improving kidney function, normalizing the urine and serum parameters, maintaining the kidney antioxidants, eliminating crystal deposition, and excretion of unwanted ions from the kidney and urinary tract.

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.

The serum glycolate concentration: its prognostic value and its correlation to surrogate markers in ethylene glycol exposures

CONTEXT

Ethylene glycol poisoning manifests as metabolic acidemia, acute kidney injury and death. The diagnosis and treatment depend on history and biochemical tests. Glycolate is a key toxic metabolite that impacts prognosis, but assay results are not widely available in a clinically useful timeframe. We quantitated the impact of serum glycolate concentration for prognostication and evaluated whether more readily available biochemical tests are acceptable surrogates for the glycolate concentration.

OBJECTIVES

The objectives of this study are to 1) assess the prognostic value of the initial glycolate concentration on the occurrence of AKI or mortality in patients with ethylene glycol exposure (prognostic study); 2) identify surrogate markers that correlate best with glycolate concentrations (surrogate study).

METHODS

A systematic review of the literature was performed using Medline/PubMed, EMBASE, Cochrane library, conference proceedings and reference lists. Human studies reporting measured glycolate concentrations were eligible. Glycolate concentrations were related to categorical clinical outcomes (acute kidney injury, mortality), and correlated with continuous surrogate biochemical measurements (anion gap, base excess, bicarbonate concentration and pH). Receiver operating characteristic curves were constructed to calculate the positive predictive values and the negative predictive values of the threshold glycolate concentrations that predict acute kidney injury and mortality. Further, glycolate concentrations corresponding to 100% negative predictive value for mortality and 95% negative predictive value for acute kidney injury were determined.

RESULTS

Of 1,531 articles identified, 655 were potentially eligible and 32 were included, reflecting 137 cases from 133 patients for the prognostic study and 154 cases from 150 patients for the surrogate study. The median glycolate concentration was 11.2 mmol/L (85.1 mg/dL, range 0-38.0 mmol/L, 0-288.8 mg/dL), 93% of patients were treated with antidotes, 80% received extracorporeal treatments, 49% developed acute kidney injury and 13% died. The glycolate concentration best predicting acute kidney injury was 12.9 mmol/L (98.0 mg/dL, sensitivity 78.5%, specificity 88.1%, positive predictive value 86.4%, negative predictive value 80.9%). The glycolate concentration threshold for a 95% negative predictive value for acute kidney injury was 6.6 mmol/L (50.2 mg/dL, sensitivity 96.9%, specificity 62.7%). The glycolate concentration best predicting mortality was 19.6 mmol/L (149.0 mg/dL, sensitivity 61.1%, specificity 81.4%, positive predictive value 33.3%, negative predictive value 93.2%). The glycolate concentration threshold for a 100% negative predictive value for mortality was 8.3 mmol/L (63.1 mg/dL, sensitivity 100.0%, specificity 35.6%). The glycolate concentration correlated best with the anion gap (R² = 0.73), followed by bicarbonate (R² = 0.57), pH (R² = 0.50) and then base excess (R² = 0.25), while there was no correlation between the glycolate and ethylene glycol concentration (R² = 0.00). These data can assist clinicians in planning treatments such as extracorporeal treatments and prognostication. Potentially, they may also provide some reassurance regarding when extracorporeal treatments can be delayed while awaiting the results of further testing in patients in whom ethylene glycol poisoning is suspected but not yet confirmed.

CONCLUSIONS

This systematic review demonstrates that the glycolate concentration predicts mortality (unlikely if <8 mmol/L [61 mg/dL]). The anion gap is a reasonable surrogate measurement for glycolate concentration in the context of ethylene glycol poisoning. The findings are mainly based on published retrospective data which have various limitations. Further prospective validation studies are of interest.

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.

Prompt Diagnosis of Ethylene Glycol Intoxication by an Unusual “Lactate Gap”: A Case Report

Introduction

Ethylene glycol intoxication can be lethal if diagnosis is delayed. Often, prompt diagnosis may need to be based on indirect laboratory findings.

Case report

We present a case of severe ethylene glycol intoxication whose diagnosis was based on an unusual “lactate gap.” The patient responded well to the treatment and had a full recovery.

Conclusion

A “lactate gap” can be helpful in establishing a diagnosis of ethylene glycol intoxication.

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.

The Diagnosis and Management of Toxic Alcohol Poisoning in the Emergency Department: A Review Article

Context:

This review discusses the range of clinical presentations seen with poisonings by the major toxic alcohols--methanol, ethylene glycol, and isopropyl alcohol. It outlines a straightforward diagnostic strategy and discusses in detail the current treatment recommendations.

Evidence acquisition:

The authors conducted a literature search of primary and secondary sources related to the topic. For treatment recommendations, search restrictions included articles published between 2008 and 2019. For background information, search restrictions included articles written from 1990 – present.

Results:

This review discusses in detail how the diagnosis can be made via clinical signs, symptoms, and laboratory values as well as the most recent treatment recommendations. This paper will also discuss the limitations of the emergency department workup and how the absence of particular laboratory findings does not necessarily rule out the diagnosis.

Conclusion:

Poisoning with methanol, ethylene glycol, and isopropanol present diagnostic and therapeutic challenges to emergency physicians. Toxic alcohol poisonings lead to an elevated osmolar gap and, with the exception of Isopropanol, a metabolic acidosis. In order for the timely initiation of life-saving treatment, emergency physicians need a solid understanding of the pathophysiology, clinical presentation, laboratory workup, and treatment.

Ethylene Glycol Toxicity in the Setting of Recurrent Ingestion: A Case Report and Literature Review

Ethylene glycol (EG) poisoning is a toxicologic emergency requiring high clinical suspicion and early diagnosis to prevent life-threatening complications. Direct EG quantification methods involve cumbersome and time-consuming laboratory tests of limited utility in the emergency setting. Accordingly, the osmolal gap is frequently employed as a surrogate screening method in cases of suspected toxic alcohol poisoning. However, the osmolal gap has several inherent limitations to be considered when used as a diagnostic tool for EG toxicity. Although many of these limitations are widely acknowledged, the clinical finding of a normal serum osmolal gap in the setting of recurrent toxic alcohol exposure is an observation that has remained largely unexplored. The purpose of this case report is to characterize the accelerated osmolal gap to anion gap conversion that may occur in the setting of chronic toxic alcohol abuse.

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.

Rapid Diagnosis of Ethylene Glycol Poisoning by Urine Microscopy

Patient: Male, 57

Final Diagnosis: Ethylene glycol poisoning

Symptoms: Unconsciousness and high anion gap

Medication: Bicarbonate • electrolyte correction • intravenous ethyl alcohol infusion • hemodialysis

Clinical Procedure: icroscopy of calcium oxalate monohydrate crystals

Specialty: Nephrology • Intensive Care Unit • Biochemistry and Immunology

Direct thermal desorption gas chromatographic determination of toxicologically relevant concentrations of ethylene glycol in whole blood

A simple and rapid method involving thermal desorption gas chromatography (TD-GC) with flame ionisation detection has been successfully developed for the determination of ethylene glycol in whole blood. No sample extraction or derivatization steps were required. The conditions required for the direct determination of ethylene glycol in whole blood were optimised and require only the addition of the internal standard, 1,2-butanediol, to the sample. A 1 μL aliquot of the sample was then introduced to the thermal desorption unit, dried, and thermally desorbed directly to the gas chromatograph. A calibration curve was constructed over the concentration range of 1.0 to 200 mM and was found to be linear over the range investigated with an R² value of 0.9997. The theoretical limit of detection based on 3σ was calculated to be 50.2 μM (3.11 mg L^-1). No issues with carryover were recorded. No interferences were recorded from endogenous blood components or a number of commonly occurring alcohols. The proposed method was evaluated by carrying out replicate ethylene glycol determinations on fortified whole blood samples at the levels of 12.5 mM, 20.0 mM, 31.2 mM, 100 mM and 200 mM comparable to commonly reported blood levels in intoxications. Mean recoveries of between 84.8% and 107% were obtained with coefficients of variation of between 1.7% and 5.8%. These data suggest that the method holds promise for applications in toxicology, where a rapid, reliable method to confirm ethylene glycol poisoning is required.

Effect of repeated administration of 4-methylpyrazole on renal function and lipid peroxidation products in rat kidney after ethylene glycol poisoning

Toxic effects of ethylene glycol (EG) and its metabolites are mainly related to metabolic acidosis and kidney damage. EG biotransformation involving CYP2E1 affects the oxidant-antioxidant balance. The study assessed the effect of repeated administration of 4-methylpyrazole (4MP, 15mg/kg b.w. after 2h, followed by 10mg/kg b.w. every 12h) on renal function (creatinine, urea and urinary protein levels) as well as products of kidney's lipid peroxidation (MDA and TBARS levels) in rats poisoned with EG (5745mg/kg b.w.). Serum EG and glycolic acid (GA) concentrations were measured throughout the experiment. Repeated administration of 4MP reduced the rate of EG elimination, extended the period of EG persistence in serum and significantly limited formation of GA. The study showed the temporary intensification of kidney oxidative processes that correlated with changes in kidney function. It was found that the use of 4MP in EG poisoning inhibited its biotransformation to toxic metabolites, but simultaneously intensified oxidative damages in kidneys.