Kidney outcomes after methanol and ethylene glycol poisoning: a systematic review and meta-analysis.

INTRODUCTION: Ingestions with methanol, ethylene glycol, diethylene glycol, propylene glycol, and isopropanol are rare yet exceedingly dangerous conditions that may require emergent management with kidney replacement therapy. Little is known regarding short- and long-term kidney outcomes post-ingestion. OBJECTIVES: To comprehensively synthesize existing evidence regarding short- and long-term kidney and other outcomes of adult patients following these poisonings. METHODS: We developed a search strategy in MEDLINE via OVID and then translated it into other databases including EMBASE (via OVID), PubMed, CENTRAL (via OVID). The databases were searched from their dates of inception to 29 July 2021. A grey literature search was conducted in the International Traditional Medicine Clinical Trial Registry and ClinicalTrials.gov. All interventional and observational studies and case series with ≥ five participants that reported on the outcomes of toxic alcohol (methanol, ethylene glycol, diethylene glycol, propylene glycol and isopropanol) poisonings in adult patients ≥18 years old were included. Studies that reported mortality, kidney outcomes and/or complications attributed to toxic alcohol poisoning were eligible. RESULTS: The search strategy identified 1,221 citations. Sixty-seven studies (13 retrospective observational studies, one prospective observational study, 53 case series) met inclusion criteria (total N = 2,327 participants). No randomized controlled trials were identified per our prespecified criteria. Generally, included studies had small sample sizes (median of 27 participants) and were of low quality. Methanol and/or ethylene glycol poisoning made up 94.1% of included studies, whereas one study reported on isopropanol and none reported on propylene glycol. Results of the 13 observational studies of methanol and/or ethylene glycol poisoning were pooled for meta-analyses. The pooled in-hospital mortality estimates amongst patients with methanol and ethylene glycol poisoning were 24 and 11%, respectively. A more recent year of publication, female sex and mean age were associated with lower in-hospital mortality amongst individuals with ethylene glycol poisoning. Although hemodialysis was the most frequently employed kidney replacement therapy, the indications for initiation of this therapy were not reported in the majority of studies. At hospital discharge, kidney recovery occurred in 64.7-96.3% of patients with ethylene glycol poisoning. In studies of methanol and/or ethylene glycol poisoning, 2-3.7% of individuals required ongoing dialysis. Only one study reported post-discharge mortality. Furthermore, long-term toxic alcohol-mediated sequelae, such as visual and neurologic outcomes, were scarcely reported. DISCUSSION: Ingestions of methanol and ethylene glycol were associated with a significant short-term risk of mortality. Although a wealth of literature in the form of case reports and case series exists, high-quality evidence regarding kidney outcomes after these poisonings is lacking. We identified a paucity of standardized reporting in clinical presentations, therapeutics and outcomes amongst adults with toxic alcohol poisoning. Amongst the included studies, there was substantial heterogeneity encompassing study type, outcomes, duration of follow-up and treatment modalities. These sources of heterogeneity restricted our ability to perform comprehensive meta-analyses of all outcomes of interest. An additional limitation is the lack of studies pertaining to propylene glycol and the paucity of data on isopropanol. CONCLUSIONS: The indications for hemodialysis, long-term kidney recovery and long-term mortality risk vary widely in these poisonings and are inconsistently reported in the literature. This highlights the need for further research with standardized reporting of baseline kidney function, indications for initiation of kidney replacement therapy and short-term and long-term kidney outcomes. REGISTRATION: This systematic review protocol is registered at PROSPERO, CRD42018101955.

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 three biological gaps and hyperoxaluria in ethylene glycol poisoning: case presentation and review.

Ethylene glycol is a toxic alcohol which may induce significant toxicity when ingested accidentally or intentionally. The main clinical complications of EG poisoning include central nervous system depression, cardiorespiratory instability and renal failure, which may be lethal if improperly treated. Although the demonstration of high plasma levels of ethylene glycol confirms the intoxication, such measurements are generally not obtained in the acute setting and can be misleading due to the rapid metabolism of EG. This implies the need for alternative, indirect, diagnostic methods, which reflect the metabolic fate of EG. These include an early and transient osmolar gap, followed by an anion gap metabolic acidosis and hyperoxaluria. Another frequent finding is a lactate gap between various methods of lactate measurements. An appropriate knowledge of these laboratory findings is essential for the diagnosis of EG poisoning, and for the initiation of antidote therapy (fomepizole) and hemodialysis in selected cases. These features are illustrated by the presentation of a prototypical case of EG poisoning, in which an incomplete diagnostic workup on hospital admission resulted in an unnecessary laparotomy and a significant delay in the management of the intoxication.

Spurious point-of-care lactate elevation in ethylene glycol intoxication: rediscovering a clinical pearl.

A 76-year-old man was found unresponsive and brought to the emergency department. Initial workup showed profound lactic acidosis on a point-of-care arterial blood gas, without clinical signs of hypoperfusion. Investigations for types A and B lactic acidosis revealed no unifying diagnosis to explain both his altered mental status and profound lactic acidosis. A toxicology workup revealed an increased osmolar gap and an elevated ethylene glycol level. The lactic acidosis and his mental status completely normalised within 8 hours of renal replacement therapy initiation and fomepizole administration. Ethylene glycol metabolites have similar molecular structure with L-lactate. Some blood gas analysers are unable to differentiate them, resulting in an artefactual lactate elevation. Our case highlights the importance of recognising a falsely elevated lactate, which should raise clinical suspicion of ethylene glycol poisoning, as the treatment is time-sensitive to prevent complications and mortality.

Distinguishing between toxic alcohol ingestion vs alcoholic ketoacidosis: how can we tell the difference?

CONTEXT: Anion gap metabolic acidosis (AGMA) is common in patients presenting for emergency care. While some disease processes and ingestions are easily excluded, diagnosing toxic alcohol (TA) ingestion can be challenging. This is especially true if drug concentrations are not readily available, which forces clinicians to rely on surrogate markers. Like TA ingestion, alcoholic ketoacidosis (AKA) produces an elevated osmol gap and an AGMA. The aim of this study was to identify risk factors suggestive of AKA when TA ingestion was the primary alternative differential diagnosis. We hypothesized that the odds of an AKA diagnosis would increase as ethanol concentration increased. METHODS: This was a retrospective analysis of data from 2000 through 2019 from a single US Poison Control Center. Records were reviewed to identify cases coded as "methanol" or "ethylene glycol"; or coded as "alcohol" or "ethanol with acidosis." The case definition for AKA required: (1) documented alcohol use disorder; (2) urine or serum ketones or elevated blood beta-hydroxybutyrate concentration; (3) anion gap ≥ 14 mmol/L. The inclusion criterion for TAs was a detectable methanol or ethylene glycol concentration. RESULTS: Of 699 patients screened, 86 were diagnosed with AKA and 36 were diagnosed with TA ingestion. As ethanol concentration increased, the odds of an AKA diagnosis significantly increased (OR = 1.016, 95% CI 1.002-1.031, p = .03). CONCLUSIONS: In this retrospective analysis, the odds of diagnosing AKA instead of TA ingestion increased as ethanol concentration increased. The limited ability of common clinical factors to differentiate these diagnoses highlights the need to obtain quantitative TA concentrations in real time. Until prospective validation, interpretation of ketone concentrations and toxic alcohol concentrations (when available) will continue to guide decision making.

[Simplified laboratory analysis of ethylene glycol allows improved management of poisoning cases]. / Förenklad analys av etylenglykol kan ge snabbare diagnos vid förgiftningsfall.

Toxicological analysis constitutes an important part of the acute treatment of poisonings. Timely laboratory results are essential for the patient to be diagnosed and treated appropriately, but also to exclude poisoning and avoid unnecessary overtreatment. Ingestion of ethylene glycol may cause acute kidney injury and, in severe cases, death, unless treated early with an antidote (ethanol infusion or fomepizole) to inhibit the formation of toxic metabolites. Diagnosis of poisoning is based on detection of ethylene glycol in plasma or serum, but a challenge remains that acute toxicology service is only available at major hospital laboratories using gas chromatography. A simple enzymatic method for the quantification of ethylene glycol (Catachem) was evaluated as a complement to currently used methods and demonstrated to provide fast and accurate measurement in a clinically relevant concentration range (1-80 mmol/l) with a minimal risk of analytical interference. The method is suitable for use on several automated clinical chemistry analyzers. Use of the enzymatic method can improve availability of acute toxicology service for ethylene glycol and contribute to better healthcare from both a patient and health resource perspective.

Analysis of fomepizole safety based on a 16-year post-marketing experience in France.

Introduction: Fomepizole has been recommended as first-line antidote to treat ethylene glycol and methanol poisoning. Despite more than 30 years of utilization, the safety of fomepizole when used clinically has not been well documented. Based on the long-standing clinical experience with fomepizole in France, we investigated its safety profile in patients treated for suspected toxic alcohol poisoning.Methods: We designed a 16-year post-marketing study to evaluate the indications for fomepizole prescriptions and to investigate its safety. Data were retrospectively collected using a standardized questionnaire sent each month by post to each French hospital that ordered fomepizole during the month before. The response rate to our survey was 59%.Results: Five hundred and thirty-six patients [188 females/348 males; age, 46 years [34-55] (median [25th-75th percentiles])] were treated with fomepizole [cumulative dose, 18.6 mg/kg [15.5-26.3] (1,268 mg [900-2,100])]. Ethylene glycol/methanol poisoning was confirmed in 275 patients (51%) while a nontoxic exposure was diagnosed in 147 patients (27%). Toxic alcohol poisoning was misdiagnosed in the remaining 114 patients (21%), before the assessment of an alternative poisoning or non-poisoning diagnosis. Fifty adverse reactions were attributed to fomepizole in 36 patients (7%) including general reactions (N = 22), local reactions (N = 22) and laboratory test impairments (N = 6). All were considered mild and transient. None required stopping fomepizole. The most frequent adverse effects were injection site pain/burning (N = 13), nausea/vomiting (N = 8), vessel puncture site inflammation (N = 7), drowsiness/confusion (N = 5) and serum aminotransferase elevation (N = 3). None of the fatalities (N = 37, 7%) or persistent symptoms on discharge (N = 9; 2%) was related to fomepizole.Conclusion: Our longitudinal cohort study supports the safety of fomepizole administered to treat presumed EG and methanol poisoning.

[A Sweet Drink with Consequences]. / Ein süsser Drink mit Folgen.

A Sweet Drink with Consequences Abstract. Intoxications with ethylene glycol are rare, however, small quantities from the substance can be life-threatening. Regarding the treatment it is important to recognize the intoxication quickly and to immediately start the appropriate treatment. Intoxications with ethylene glycol or with methanol should always be considered as differential diagnosis in patients with severe metabolic acidosis. It is also very important to calculate the osmolal gap.

Ethylene glycol intoxication following brake fluid ingestion complicated with unilateral facial nerve palsy: a case report.

BACKGROUND: Brake oil is an automobile transmission fluid composed of a mixture of toxic alcohols such as ethylene glycols and glycol ethers. Both accidental and intentional ingestion cases have been reported and they can present with multisystem involvement. Life-threatening complications evolve from deleterious effects on cardiopulmonary and renal systems. Effects on neurological and gastrointestinal systems give rise to a multitude of complications although non-fatal in nature. The biochemical panel consists of a high concentration of ethylene glycol with severe metabolic acidosis, high anion gap, high osmolar gap, oxaluria, and hypocalcemia. The mainstay of treatment is enhanced elimination of ethylene glycol and its metabolites by hemodialysis, together with general supportive care, gastric decontamination, and vitamins such as thiamine and pyridoxine to minimize the adverse effects of intoxication. CASE PRESENTATION: A 26-year-old Sinhalese woman presented with reduced urine output, shortness of breath, reduced level of consciousness, abdominal pain, and vomiting with mild degree fever of 2 days' duration. She had bilateral lower limb edema, crepitations over bilateral lower lung fields, and right-sided lower motor type facial nerve palsy. Investigations showed severe metabolic acidosis with high anion gap and high osmolar gap. With regular hemodialysis she made a complete recovery after 3 months. CONCLUSION: Even without a clear history of poisoning, the presence of a high anion, high osmolar gap metabolic acidosis should prompt one to search for ethylene glycol ingestion. Uncommon manifestations like cranial neuropathies need to be examined and considered. Timely aggressive treatment leads to a better prognosis.

Stiripentol protects against calcium oxalate nephrolithiasis and ethylene glycol poisoning.

Increased urinary oxalate excretion (hyperoxaluria) promotes the formation of calcium oxalate crystals. Monogenic diseases due to hepatic enzymes deficiency result in chronic hyperoxaluria, promoting end-stage renal disease in children and young adults. Ethylene glycol poisoning also results in hyperoxaluria promoting acute renal failure and frequently death. Stiripentol is an antiepileptic drug used to treat children affected by Dravet syndrome, possibly by inhibiting neuronal lactate dehydrogenase 5 isoenzyme. As this isoenzyme is also the last step of hepatic oxalate production, we hypothesized that Stiripentol would potentially reduce hepatic oxalate production and urine oxalate excretion. In vitro, Stiripentol decreased in a dose-dependent manner the synthesis of oxalate by hepatocytes. In vivo, Stiripentol oral administration reduced significantly urine oxalate excretion in rats. Stiripentol protected kidneys against calcium oxalate crystal deposits in acute ethylene glycol intoxication and chronic calcium oxalate nephropathy models. In both models, Stiripentol improved significantly renal function. Patients affected by Dravet syndrome and treated with Stiripentol had a lower urine oxalate excretion than control patients. A young girl affected by severe type I hyperoxaluria received Stiripentol for several weeks: urine oxalate excretion decreased by two-thirds. Stiripentol is a promising potential therapy against genetic hyperoxaluria and ethylene glycol poisoning.

Ethylene glycol: Evidence of glucuronidation in vivo shown by analysis of clinical toxicology samples.

In the search for improved laboratory methods for the diagnosis of ethylene glycol poisoning, the in vivo formation of a glucuronide metabolite of ethylene glycol was hypothesized. Chemically pure standards of the ß-O-glucuronide of ethylene glycol (EG-GLUC) and a deuterated analog (d4 -EG-GLUC) were synthesized. A high-performance liquid chromatography and tandem mass spectrometry method for determination of EG-GLUC in serum after ultrafiltration was validated. Inter-assay precision (%RSD) was 3.9% to 15.1% and inter-assay %bias was -2.8% to 12.2%. The measuring range was 2-100 µmol/L (0.48-24 mg/L). Specificity testing showed no endogenous amounts in routine clinical samples (n = 40). The method was used to analyze authentic, clinical serum samples (n = 31) from patients intoxicated with ethylene glycol. EG-GLUC was quantified in 15 of these samples, with a mean concentration of 6.5 µmol/L (1.6 mg/L), ranging from 2.3 to 15.6 µmol/L (0.55 to 3.7 mg/L). In five samples, EG-GLUC was detected below the limit of quantification (2 µmol/L) and it was below the limit of detection in 11 samples (1 µmol/L). Compared to the millimolar concentrations of ethylene glycol present in blood after intoxications and potentially available for conjugation, the concentrations of EG-GLUC found in clinical serum samples are very low, but comparable to concentrations of ethyl glucuronide after medium dose ethanol intake. In theory, EG-GLUC has a potential value as a biomarker for ethylene glycol intake, but the pharmacokinetic properties, in vivo/vitro stability and the biosynthetic pathways of EG-GLUC must be further studied in a larger number of patients and other biological matrices.

Ethylene glycol and methanol ingestion cared for by tele-emergency pharmacy and tele-emergency medicine.

We believe this is the first documented case of a critically ill patient managed by telepharmacy in a remote, rural critical access hospital. We outline the case and the benefits of telepharmacy in under-resourced, rural critical access emergency departments.

[Antifreeze poisoning : The case of a patient with repeated ethylene glycol poisoning]. / Intoxikation nach Frostschutzmittelaufnahme : Der Fall eines Patienten nach wiederholter Ethylenglykolintoxikation.

Ethylene glycol poisoning of incidental or suicidal intention can cause life-threatening metabolic acidosis, diverse secondary damage, and even lead to death. Beside hemodialysis effective therapy consists of the administration of fomepizole and ethanol. We describe a patient after repeated ethylene glycol poisoning with high anion gap metabolic acidosis and acute renal failure. Using hemodialysis, with dialysate containing a specific amount of ethanol, and intravenous ethanol administration we were able to prevent severe secondary organ damage.

The importance of the histopathological examination in lethal acute intoxication with ethylene glycol. Case report.

Ethylene glycol is a toxic alcohol that is mainly introduced into an organism through the digestive pathway. Its priority toxic metabolites are glycolic acid and oxalic acid. We present the case of a young person, of the male persuasion, without any personal pathological history, found unconscious and presenting signs of violence. The patient is emergency hospitalized presenting coma, convulsive syndrome, severe metabolic acidosis and a positive result for alcoholism. Anamnestic data is extremely poor. The results of the clinical and paraclinical examinations suggest a possible poisoning with toxic alcohols. Despite the drug treatment and the hemodialysis, the evolution is unfavorable, resulting in death one week after admission. Through the forensic examination, the followings were found: cerebral and leptomeningeal edema, focal cerebral microhemorrhages, bronchopneumonia, septic spleen, shock kidney, hepatic fatty dystrophy, excoriated plaques in the head area. The histopathological (HP) examination confirms the macroscopic diagnosis and identifies the presence of calcium oxalate crystals in the kidney tubules. Subsequently, the toxicological examination of the biological samples taken from the corpse at the forensic examination, confirms the presence of the glycolic acid. Postmortem, the investigation conducted by the criminal investigation authorities confirms the oral ingestion of antifreeze. The absence of a positive history, along with alcohol consumption, nonspecific clinical symptomatology and the absence of calcium oxalate in urine are trap elements in the diagnosis of acute ethylene glycol poisoning. The presence of calcium oxalate in tissues, identified through the HP examination, is an extremely important factor when establishing the cause of death.