Antidotes for methanol and ethylene glycol poisoning

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.

Awareness raising and dealing with methanol poisoning based on effective strategies

Intoxication with methanol most commonly occurs as a consequence of ingesting, inhaling, or coming into contact with formulations that include methanol as a base. Clinical manifestations of methanol poisoning include suppression of the central nervous system, gastrointestinal symptoms, and decompensated metabolic acidosis, which is associated with impaired vision and either early or late blindness within 0.5-4 h after ingestion. After ingestion, methanol concentrations in the blood that are greater than 50 mg/dl should raise some concern. Ingested methanol is typically digested by alcohol dehydrogenase (ADH), and it is subsequently redistributed to the body's water to attain a volume distribution that is about equivalent to 0.77 L/kg. Moreover, it is removed from the body as its natural, unchanged parent molecules. Due to the fact that methanol poisoning is relatively uncommon but frequently involves a large number of victims at the same time, this type of incident occupies a special position in the field of clinical toxicology. The beginning of the COVID-19 pandemic has resulted in an increase in erroneous assumptions regarding the preventative capability of methanol in comparison to viral infection. More than 1000 Iranians fell ill, and more than 300 of them passed away in March of this year after they consumed methanol in the expectation that it would protect them from a new coronavirus. The Atlanta epidemic, which involved 323 individuals and resulted in the deaths of 41, is one example of mass poisoning. Another example is the Kristiansand outbreak, which involved 70 people and resulted in the deaths of three. In 2003, the AAPCC received reports of more than one thousand pediatric exposures. Since methanol poisoning is associated with high mortality rates, it is vital that the condition be addressed seriously and managed as quickly as feasible. The objective of this review was to raise awareness about the mechanism and metabolism of methanol toxicity, the introduction of therapeutic interventions such as gastrointestinal decontamination and methanol metabolism inhibition, the correction of metabolic disturbances, and the establishment of novel diagnostic/screening nanoparticle-based strategies for methanol poisoning such as the discovery of ADH inhibitors as well as the detection of the adulteration of alcoholic drinks by nanoparticles in order to prevent methanol poisoning. In conclusion, increasing warnings and knowledge about clinical manifestations, medical interventions, and novel strategies for methanol poisoning probably results in a decrease in the death load.

Risk factors associated with mortality in patients with methanol poisoning: a retrospective study

Aim: Methanol poisoning (MP) is an essential medical problem worldwide, and despite advances in diagnosis and treatment, the mortality rate in these cases is high. This study aimed to evaluate the clinical and laboratory factors to determine in-hospital mortality in patients with MP. Methods: This single-center, retrospective, observational study was conducted with adult 65 MP cases visiting the emergency department (ED) of a tertiary training and research hospital between January 01, 2017, and February 01, 2022. Data were statistically compared between survivors and non-survivors. Results: The in-hospital mortality rate was 41.5%. The rate of cases with respiratory distress, low Glasgow coma scale (GCS) (≤8), and delayed arrival to the hospital (>24 hours) was higher in the group of non-survivors compared to the group of survivors. Non-survivors had a higher anion gap (30.5 mEq/L vs. 25.5mEq/L), base excess (-25.0 mmol/L vs. -18.6 mmol/L), lactate (10.2 mmol/L vs. 2.2 mmol/L) levels, and lower pH (6.76 vs. 7.14) and bicarbonate (6.3 mmol/L vs. 10.3 mmol/L) levels than survivors (p

Methanol poisoning outbreak in Saudi Arabia: a case series

Background

Outbreaks of methanol poisoning have been described in the medical literature in different regions around the world. Even though in Saudi Arabia a few outbreaks of methanol poisoning have occurred, they remain undocumented. Herein, we describe several cases of methanol poisoning in Saudi Arabia with the goal of increasing awareness about the dangers of methanol poisoning among healthcare staff.

Case presentation

Nine middle-aged Saudi patients (five men aged 24, 26, 27, 36, and 49 years and four females aged 19, 20, 24, and 25 years) were admitted to our emergency department after alcohol consumption. All patients presented with severe metabolic acidosis and some visual impairment. Treatment was initiated based on the clinical suspicion of methanol intoxication because of laboratory test limitations and time constraints. Patients showed improvement and favorable hospital outcomes after aggressive empirical treatment.

Conclusions

Many social and cultural factors influence the lack of reporting of methanol poisoning cases in Saudi Arabia. We believe it is important to document these outbreaks to increase the knowledge among healthcare providers and promote public health awareness. A high index of suspicion and the development of local public health networks to monitor, survey, follow-up, and facilitate data exchange can help healthcare providers recognize and aggressively treat affected individuals. Early empiric and aggressive management can greatly decrease morbidity and mortality despite challenges and limited resources.

Acil Servise Başvuran Metil Alkol Zehirlenmelerinin Geriye Dönük Analizi

Objective: Methyl alcohol poisoning remains a significant cause of mortality and morbidity. This poisoning is still one of the important reasons for admission to emergency services. We aimed to examine the admission complaints, laboratory findings, treatment methods, clinical outcomes and examine the factors affecting the mortality of patients diagnosed with methyl alcohol poisoning in the emergency department. Methods: In this retrospective descriptive study, we analysed the patients who were considered to be diagnosed with methyl alcohol intoxication among those who came to our emergency department due to alcohol intoxication from June 1, 2018 to June 1, 2020. Results: The study included 20 (4.86%) individuals with methyl alcohol poisoning among 411 people who presented to the emergency department due to ethyl and methyl alcohol intake and resulting effects.The mean age of the patients was 47.35±14.2 years and 85% (n=17/20) were male. Upon reviewing the patients' admission symptoms, 70% were observed to have visual problems, 60% complaints of vomiting, 45% shortness of breath, and 40% changes in consciousness. In the study, it was revealed that 18.2%(n=2/11) females and 81.8%(n=9/11) males died, and the mortality rate was calculated as 55%(n=11/20). Conclusions: The presence of visual problems, hypotension, and coma in clinical findings, high anion gap metabolic acidosis, marked osmolar gap, an increase in lactate level, and hyperglycemia in laboratory findings may be the early signs of mortality in patients with methyl alcohol poisoning. Therefore, patients with these signs should be followed up more closely and treated.

Simultaneous 15 N polarization of several biocompatible substrates in ethanol-water mixtures by signal amplification by reversible exchange (SABRE) method

Signal amplification by reversible exchange (SABRE) is a popular method for generating strong signal enhancements in nuclear magnetic resonance (NMR). In SABRE experiments, the source of polarization is provided by the nonthermal spin order of parahydrogen (pH₂ , the H₂ molecule in its nuclear singlet spin state). Polarization formation requires that both pH₂ and a substrate molecule bind to an Ir-based complex where polarization transfer occurs. Subsequently, the complex dissociates and free polarized substrate molecules are formed. In this work, we present approaches towards biocompatible SABRE, meaning that several small biomolecules are simultaneously polarized by using the SABRE method in water-ethanol solutions at room temperature. We are able to demonstrate significant ¹⁵ N-NMR signal enhancements in water-ethanol solutions for biomolecules like nicotinamide, metronidazole, adenosine-5'-monophosphate, and 4-methylimidazole and found that the first three substrates are polarized at the same level as a well-known pyridine. We show that simultaneous polarization of several molecules is indeed feasible when the reactions are carried out at an ultralow field of about 400-500 nT. The achieved enhancements are between 100-fold and 15,000-fold. The resulting ¹⁵ N polarization (maximal value about 4% achieved for metronidazole and pyridine at 45°C) strongly depends on the sample temperature, pH₂ bubbling pressure, and pH₂ flow. One more parameter, which is important for optimizing the enhancement, is the solvent pH. Hence, this study presents a step in developing biocompatible SABRE polarization and gives a clue on how such SABRE experiments should be optimized to achieve the highest NMR signal enhancement.

Methanol poisoning in Turkey: Two outbreaks, a single center experience

OBJECTIVES

Methanol poisoning is still one of the major causes of mortality due to intoxication because of the challenging diagnosis and late hospital admissions. We aimed to evaluate epidemiological data, clinical characteristics, laboratory findings, treatment protocols, and prognosis of patients in a tertiary hospital in two different methanol outbreaks occurring in a three-year interval.

METHODS

The study was planned as a single-center and retrospective observational case series study. Patients ≥18 years of age who were admitted to the hospital between 1 September 2016 and 1 September 2019 and diagnosed with methanol poisoning were included in the study.

RESULTS

Sixty-seven patients whose data were sufficient and accessible were included in the study. Thirty-five (52.2%) patients were discharged without sequelae, 14 (20.9%) patients were discharged with sequelae (both central nervous system sequelae and visual sequelae in 3 patients, only visual sequelae in 11 patients) and 18 (26.9%) patients died. High anion gap (AG) metabolic acidosis (pH < 7.07, AG > 26.7), low Glasgow Coma Score, and increased lactate (lactate > 2.55 mmol/L) levels were found to be associated with poor outcome. Folate use in treatment did not have a statistically significant effect (p = 0.087) on the prevention of visual sequelae development, but it had a statistically significant effect on mortality (p = 0.041).

CONCLUSIONS

State of consciousness and the severity of metabolic acidosis were significant parameters associated with mortality. In addition to antidote and elimination therapies, given the benefit on mortality and low risk of adverse events, folate therapy should be considered for all patients with significant toxic methanol exposures.

Reference values for osmolal gap in healthy subjects and in medical inpatients

Methanol and ethylene glycol poisonings are associated with high morbidity and mortality rates if treatment is not initiated early. Since few hospitals measure these toxic alcohols on a 24/7 basis, calculation of the osmolal gap (OG) is an important diagnostic tool. The reference value for the OG lacks consensus. We, therefore, wanted to update the reference value for OG in presumed healthy subjects and study OG values in internal medicine patients. The OG was calculated in 285 patients at the Medical Clinic at Oslo University Hospital, and in 118 healthy blood donors at Vestfold Hospital Trust. OG was calculated by the formula: OG = Measured osmolality - calculated osmolality ((1.86 × s-sodium + s-glucose + s-urea)/0.93) mOsm/kg H₂O. In the patients, median OG was 0 mOsm/kg H₂O (interquartile range -3 to 3 mOsm/kg H₂O, range -16 to103 mOsm/kg H₂O). When corrected for one outlier, the central 95% interval for OG was -10 to 20. The healthy blood donors had a median OG of -1 mOsm/kg H₂O (interquartile range -3 to1 mOsm/kg H₂O, range -13 to 8 mOsm/kg H₂O). When corrected for outliers, the reference range was -6 to 5 mOsm/kg H₂O. Based on results from a healthy population, we suggest a reference value for the OG of ≤5 mOsm/kg H₂O, but also recommend, based on our results from medical inpatients, to keep today's practice for suspecting poisoning with toxic alcohols at an elevated OG of ≥20 mOsm/kg H₂O.

Consensus statements on the approach to patients in a methanol poisoning outbreak

Background: Methanol poisoning is an important cause of mortality and morbidity worldwide. Although it often occurs as smaller sporadic events, epidemic outbreaks are not uncommon due to the illicit manufacture and sale of alcoholic beverages.Objective: We aimed to define methanol poisoning outbreak (MPO), outline an approach to triaging an MPO, and define criteria for prioritizing antidotes, extracorporeal elimination treatments (i.e., dialysis), and indications for transferring patients in the context of an MPO.Methods: We convened a group of experts from across the world to explore geographical, socio-cultural and clinical considerations in the management of an MPO. The experts answered specific open-ended questions based on themes aligned to the goals of this project. This project used a modified Delphi process. The discussion continued until there was condensation of themes.Results: We defined MPO as a sudden increase in the number of cases of methanol poisoning during a short period of time above what is normally expected in the population in that specific geographic area. Prompt initiation of an antidote is necessary in MPOs. Scarce hemodialysis resources require triage to identify patients most likely to benefit from this treatment. The sickest patients should not be transferred unless the time for transfer is very short. Transporting extracorporeal treatment equipment and antidotes may be more efficient.Conclusion: We have developed consensus statements on the response to a methanol poisoning outbreak. These can be used in any country and will be most effective when they are discussed by health authorities and clinicians prior to an outbreak.

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.

Targeting Metalloenzymes for Therapeutic Intervention

Metalloenzymes are central to a wide range of essential biological activities, including nucleic acid modification, protein degradation, and many others. The role of metalloenzymes in these processes also makes them central for the progression of many diseases and, as such, makes metalloenzymes attractive targets for therapeutic intervention. Increasing awareness of the role metalloenzymes play in disease and their importance as a class of targets has amplified interest in the development of new strategies to develop inhibitors and ultimately useful drugs. In this Review, we provide a broad overview of several drug discovery efforts focused on metalloenzymes and attempt to map out the current landscape of high-value metalloenzyme targets.

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.

LC-ESI-MS/MS determination of 4-methylpyrazole in dog plasma and its application to a pharmacokinetic study in dogs

A simple, specific, sensitive and rapid LC-ESI-MS/MS method has been developed and validated for the quantification of 4-methylpyrazole in dog plasma using N-methylnicotinamide-d₄ as an internal standard (IS) as per regulatory guidelines. Sample preparation was accomplished through a simple protein precipitation. Chromatographic separation of 4-methylpyrazole and the IS was performed on a monolithic (Chromolith RP_18e ) column using an isocratic mobile phase comprising 0.2% formic acid in water and acetonitrile (20:80, v/v) at a flow rate of 1.0 mL/min. Elution of 4-methylpyrazole and the IS occurred at ~1.60 and 1.56 min, respectively. The total chromatographic run time was 3.2 min. A linear response function was established in the concentration range of 4.96-4955 ng/mL. The intra- and inter-day accuracy and precision were in the ranges 1.81-12.9 and 3.80-11.1%, respectively. This novel method has been applied to a pharmacokinetic study in dogs.

Sequential episodes of ethylene glycol poisoning in the same person

Ethylene glycol is a common alcohol found in many household products such as household hard surface cleaner, paints, varnish, auto glass cleaner and antifreeze. While extremely toxic and often fatal on ingestion, few cases with early presentation by the patient have resulted in death; thus, rapid diagnosis is paramount to effectively treating ethylene glycol poisoning. In this study, we compare two sequential cases of ethylene glycol poisoning in a single individual, which resulted in strikingly different outcomes.

Antidote Use in the Critically Ill Poisoned Patient

The proper use of antidotes in the intensive care setting when combined with appropriate general supportive care may reduce the morbidity and mortality associated with severe poisonings. The more commonly used antidotes that may be encountered in the intensive care unit ( N-acetylcysteine, ethanol, fomepizole, physostigmine, naloxone, flumazenil, sodium bicarbonate, octreotide, pyridoxine, cyanide antidote kit, pralidoxime, atropine, digoxin immune Fab, glucagon, calcium gluconate and chloride, deferoxamine, phytonadione, botulism antitoxin, methylene blue, and Crotaline snake antivenom) are reviewed. Proper indications for their use and knowledge of the possible adverse effects accompanying antidotal therapy will allow the physician to appropriately manage the severely poisoned patient.

Treatment with 4-methylpyrazole modulated stellate cells and natural killer cells and ameliorated liver fibrosis in mice

Background & Aims

Accumulating evidence suggests that retinol and its metabolites are closely associated with liver fibrogenesis. Recently, we demonstrated that genetic ablation of alcohol dehydrogenase 3 (ADH3), a retinol metabolizing gene that is expressed in hepatic stellate cells (HSCs) and natural killer (NK) cells, attenuated liver fibrosis in mice. In the current study, we investigated whether pharmacological ablation of ADH3 has therapeutic effects on experimentally induced liver fibrosis in mice.

Methods

Liver fibrosis was induced by intraperitoneal injections of carbon tetrachloride (CCl₄) or bile duct ligation (BDL) for two weeks. To inhibit ADH3-mediated retinol metabolism, 10 μg 4-methylpyrazole (4-MP)/g of body weight was administered to mice treated with CCl₄ or subjected to BDL. The mice were sacrificed at week 2 to evaluate the regression of liver fibrosis. Liver sections were stained for collagen and α-smooth muscle actin (α-SMA). In addition, HSCs and NK cells were isolated from control and treated mice livers for molecular and immunological studies.

Results

Treatment with 4-MP attenuated CCl₄- and BDL-induced liver fibrosis in mice, without any adverse effects. HSCs from 4-MP treated mice depicted decreased levels of retinoic acids and increased retinol content than HSCs from control mice. In addition, the expression of α-SMA, transforming growth factor-β1 (TGF-β1), and type I collagen α1 was significantly reduced in the HSCs of 4-MP treated mice compared to the HSCs from control mice. Furthermore, inhibition of retinol metabolism by 4-MP increased interferon-γ production in NK cells, resulting in increased apoptosis of activated HSCs.

Conclusions

Based on our data, we conclude that inhibition of retinol metabolism by 4-MP ameliorates liver fibrosis in mice through activation of NK cells and suppression of HSCs. Therefore, retinol and its metabolizing enzyme, ADH3, might be potential targets for therapeutic intervention of liver fibrosis.

Fomepizole in the treatment of ethylene glycol poisoning

The management of ethylene glycol poisoning is reviewed, with a focus on the use of the new antidote fomepizole. Ethylene glycol is a widely used industrial agent that is also easily obtained commercially, usually as radiator antifreeze. Ingestion of as little as 30 to 60 mL can result in death or serious permanent disability. Traditional management of poisoning includes the use of ethanol, with or without hemodialysis. Activated charcoal is not indicated, and gastric lavage may be beneficial only in the first hour after ingestion. Cofactors such as pyridoxine and thiamine may be beneficial in patients deficient in these vitamins. A new antidote, fomepizole, has recently been approved for use in Canada. Like ethanol, it is a competitive inhibitor of alcohol dehydrogenase. Potential benefits of fomepizole include its ease of administration and lack of serious adverse effects. Fomepizole may be recommended over ethanol in situations in which avoidance of ethanol-induced side effects is imperative or when ethanol is not readily available. Further studies are required to verify its comparative efficacy and cost-effectiveness compared to ethanol.

Methanol and ethylene glycol poisoning: a case study and review of current literature

Poisoning is an uncommon but potentially fatal outcome of toxic alcohol ingestion. The toxic alcohols methanol, ethylene glycol and isopropyl alcohol are commonly found in household and commercial products. Because the toxic effects are caused by the metabolites of methanol and ethylene glycol rather than the agents themselves, there is often a substantial delay between ingestion and onset of clinical toxicity. Anion and osmolar gaps are often used for the diagnosis and exclusion of these sometimes subtle overdoses. The pitfalls of using these tests to rule out alcohol ingestion are reviewed. Ethanol infusion is the traditional therapy for such overdoses. In addition to the pathophysiology and clinical findings in poisoning, recent evidence for the use of fomepizole and adjuvant therapies is reviewed.

Recommendations for the role of extracorporeal treatments in the management of acute methanol poisoning: a systematic review and consensus statement

OBJECTIVE

Methanol poisoning can induce death and disability. Treatment includes the administration of antidotes (ethanol or fomepizole and folic/folinic acid) and consideration of extracorporeal treatment for correction of acidemia and/or enhanced elimination. The Extracorporeal Treatments in Poisoning workgroup aimed to develop evidence-based consensus recommendations for extracorporeal treatment in methanol poisoning.

DESIGN AND METHODS

Utilizing predetermined methods, we conducted a systematic review of the literature. Two hundred seventy-two relevant publications were identified but publication and selection biases were noted. Data on clinical outcomes and dialyzability were collated and a two-round modified Delphi process was used to reach a consensus.

RESULTS

Recommended indications for extracorporeal treatment: Severe methanol poisoning including any of the following being attributed to methanol: coma, seizures, new vision deficits, metabolic acidosis with blood pH ≤ 7.15, persistent metabolic acidosis despite adequate supportive measures and antidotes, serum anion gap higher than 24 mmol/L; or, serum methanol concentration 1) greater than 700 mg/L (21.8 mmol/L) in the context of fomepizole therapy, 2) greater than 600 mg/L or 18.7 mmol/L in the context of ethanol treatment, 3) greater than 500 mg/L or 15.6 mmol/L in the absence of an alcohol dehydrogenase blocker; in the absence of a methanol concentration, the osmolal/osmolar gap may be informative; or, in the context of impaired kidney function. Intermittent hemodialysis is the modality of choice and continuous modalities are acceptable alternatives. Extracorporeal treatment can be terminated when the methanol concentration is <200 mg/L or 6.2 mmol/L and a clinical improvement is observed. Extracorporeal Treatments in Poisoning inhibitors and folic/folinic acid should be continued during extracorporeal treatment. General considerations: Antidotes and extracorporeal treatment should be initiated urgently in the context of severe poisoning. The duration of extracorporeal treatment extracorporeal treatment depends on the type of extracorporeal treatment used and the methanol exposure. Indications for extracorporeal treatment are based on risk factors for poor outcomes. The relative importance of individual indications for the triaging of patients for extracorporeal treatment, in the context of an epidemic when need exceeds resources, is unknown. In the absence of severe poisoning but if the methanol concentration is elevated and there is adequate alcohol dehydrogenase blockade, extracorporeal treatment is not immediately required. Systemic anticoagulation should be avoided during extracorporeal treatment because it may increase the development or severity of intracerebral hemorrhage.

CONCLUSION

Extracorporeal treatment has a valuable role in the treatment of patients with methanol poisoning. A range of clinical indications for extracorporeal treatment is provided and duration of therapy can be guided through the careful monitoring of biomarkers of exposure and toxicity. In the absence of severe poisoning, the decision to use extracorporeal treatment is determined by balancing the cost and complications of extracorporeal treatment to that of fomepizole or ethanol. Given regional differences in cost and availability of fomepizole and extracorporeal treatment, these decisions must be made at a local level.

Contribution of liver alcohol dehydrogenase to metabolism of alcohols in rats

The kinetics of oxidation of various alcohols by purified rat liver alcohol dehydrogenase (ADH) were compared with the kinetics of elimination of the alcohols in rats in order to investigate the roles of ADH and other factors that contribute to the rates of metabolism of alcohols. Primary alcohols (ethanol, 1-propanol, 1-butanol, 2-methyl-1-propanol, 3-methyl-1-butanol) and diols (1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol) were eliminated in rats with zero-order kinetics at doses of 5-20 mmol/kg. Ethanol was eliminated most rapidly, at 7.9 mmol/kgh. Secondary alcohols (2-propanol-d7, 2-propanol, 2-butanol, 3-pentanol, cyclopentanol, cyclohexanol) were eliminated with first order kinetics at doses of 5-10 mmol/kg, and the corresponding ketones were formed and slowly eliminated with zero or first order kinetics. The rates of elimination of various alcohols were inhibited on average 73% (55% for 2-propanol to 90% for ethanol) by 1 mmol/kg of 4-methylpyrazole, a good inhibitor of ADH, indicating a major role for ADH in the metabolism of the alcohols. The Michaelis kinetic constants from in vitro studies (pH 7.3, 37 °C) with isolated rat liver enzyme were used to calculate the expected relative rates of metabolism in rats. The rates of elimination generally increased with increased activity of ADH, but a maximum rate of 6±1 mmol/kg h was observed for the best substrates, suggesting that ADH activity is not solely rate-limiting. Because secondary alcohols only require one NAD(+) for the conversion to ketones whereas primary alcohols require two equivalents of NAD(+) for oxidation to the carboxylic acids, it appears that the rate of oxidation of NADH to NAD(+) is not a major limiting factor for metabolism of these alcohols, but the rate-limiting factors are yet to be identified.

Bibliometric profile of the global scientific research on methanol poisoning (1902-2012)

BACKGROUND

Methanol poisoning is on the rise and has been associated with high morbidity and mortality; it has resulted in growing research in the field of toxicology. The aim of this study was to reveal underlying patterns in scientific outputs related to methanol poisoning at the global level by evaluating different bibliometric indices.

METHODS

We searched for publications that contained specific words regarding methanol poisoning in Scopus database.

RESULTS

A total of 912 articles, with 8,317 citations and with an average of 9.1 citations per document, were retrieved on methanol poisoning, and the bulk of the articles were published from the USA (20.9%), followed by Spain (4.4%), Canada (4.3%), India (3.1%), and France (3.0%). The articles were published belonging to 57 countries. No data related to methanol poisoning were published from 155 (73.1%) out of 212 countries. Twenty-one documents (2.3%) were published in Clinical Toxicology, whereas 18 (2.0%) were published in The Lancet.

CONCLUSIONS

Scientific production related to methanol poisoning is increasing. articles have been published in a wide range of journals with a variety of subject areas, most notably clinical toxicology; and the country with the greatest production was the USA.

Evaluation of two point-of-care ethylene glycol tests for dogs

OBJECTIVE

To evaluate 2 point-of-care ethylene glycol (EG) tests in dogs.

DESIGN

Prospective, randomized, blinded laboratory evaluation.

SETTING

University teaching hospital.

ANIMALS

Ten healthy adult dogs.

INTERVENTIONS

Jugular venipuncture and in vitro evaluation for detection of EG in canine blood.

MEASUREMENTS

Whole blood samples were centrifuged and separated, and the plasma was divided into 30 aliquots. The aliquots were mixed with EG to provide EG concentrations ranging from 0 to 100 mg/dL. The EG concentration of each sample was confirmed using gas chromatography. For the VetSpec EG Qualitative Reagent Test Kit, 100 μL of each sample was added to test vials and compared with 20 and 50 mg/dL reference vials. For the Kacey EG Test Strips, 20 μL of each sample was added to the test circle and compared with the color chart provided by the manufacturer. For each test, samples were prepared in groups of 5 and presented in randomized order to 2 readers who were blinded to the presumed EG concentration. Samples were scored as negative, 20-50 mg/dL, or greater than 50 mg/dL. For each test, the sensitivity and specificity for detecting EG was calculated. Cohen's unweighted kappa coefficient was calculated to determine the degree of agreement between readers.

MAIN RESULTS

For detecting EG, the Kacey EG Test Strips had excellent sensitivity and specificity (both 100%) and good agreement between readers. The VetSpec EG Qualitative Reagent Test Kit was less sensitive and specific (65% and 70% for the first reader, 95% and 40% for the second) with less agreement.

CONCLUSIONS

Of the 2 systems evaluated, the Kacey EG Test Strips displayed greater accuracy and ease of use.

Toxicologic emergencies in the intensive care unit: management using reversal agents and antidotes

PURPOSE

To review the most common drugs implicated in overdoses admitted to the intensive care unit focusing on antidotes and reversal agents used in their management.

SUMMARY

Poisonings and overdoses due to pharmaceutical agents result in more than 100 000 critical care unit admissions each year. Ingestion of toxic alcohols, calcium channel blockers, beta-adrenergic antagonists, benzodiazepines, opioids, acetaminophen, tricyclic antidepressants, and salicylates are associated with a high rate of morbidity and mortality. Reviewing the mechanism of toxicity due to specific agents along with the mechanism of action, dosing, and adverse effects of appropriate antidotes is important for the successful management of these patients within the critical care unit.

CONCLUSION

Understanding the most prevalent overdoses and their management using reversal agents and antidotes is essential to the overall treatment of these critically ill patients.

Intermittent hemodialysis is superior to continuous veno-venous hemodialysis/hemodiafiltration to eliminate methanol and formate during treatment for methanol poisoning

During an outbreak of methanol poisonings in the Czech Republic in 2012, we were able to study methanol and formate elimination half-lives during intermittent hemodialysis (IHD) and continuous veno-venous hemodialysis/hemodiafiltration (CVVHD/HDF) and the relative impact of dialysate and blood flow rates on elimination. Data were obtained from 11 IHD and 13 CVVHD/HDF patients. Serum methanol and formate concentrations were measured by gas chromatography and an enzymatic method. The groups were relatively comparable, but the CVVHD/HDF group was significantly more acidotic (mean pH 6.9 vs. 7.1 IHD). The mean elimination half-life of methanol was 3.7 and formate 1.6 h with IHD, versus 8.1 and 3.6 h, respectively, with CVVHD/HDF (both significant). The 54% greater reduction in methanol and 56% reduction in formate elimination half-life during IHD resulted from the higher blood and dialysate flow rates. Increased blood and dialysate flow on the CVVHD/HDF also increased elimination significantly. Thus, IHD is superior to CVVHD/HDF for more rapid methanol and formate elimination, and if CVVHD/HDF is the only treatment available then elimination is greater with greater blood and dialysate flow rates.

Acute kidney injury with oxalate deposition in a patient with a high anion gap metabolic acidosis and a normal osmolal gap

BACKGROUND

Ethylene glycol ingestion can lead to acute kidney injury from tubular deposition of oxalate crystals.  The diagnosis of ethylene glycol intoxication is based on a history of ingestion, clinical examination, high anion gap metabolic acidosis, high osmolal gap, and a measured serum level of ethylene glycol.  However, depending on the delay in time from ingestion to arrival to a hospital, the osmolal gap may become normal, thereby creating a confusing clinic picture for the treating clinician.

CASE

A 71 year-old man with a history of alcohol abuse had been unconscious for an unknown period of time.  Upon hospitalization, he was found to have a high anion gap metabolic acidosis but a normal serum osmolal gap and subsequently developed acute kidney injury.  The serum lactic acid and glucose levels were unremarkable, and there were no ketones in the serum. Urine analysis showed numerous red blood cells and calcium oxalate crystals.  The renal biopsy showed multiple oxalate crystals in the renal tubules demonstrating birefringence under polarized light. Given the history of alcohol abuse, the clinical presentation, the unexplained high anion gap metabolic acidosis, and the biopsy findings, ethylene glycol intoxication was deemed the most likely diagnosis.

CONCLUSIONS

In cases of ethylene glycol intoxication, a high serum osmolal gap is supportive of ethylene glycol intoxication, but a normal serum osmolal gap does not exclude the diagnosis, especially when the time of ingestion is unknown. Physicians should be aware of potentially normal serum osmolal gap values in cases of ethylene glycol intoxication.

Antidotes for toxicological emergencies: a practical review

PURPOSE

Appropriate therapies for commonly encountered poisonings, medication overdoses, and other toxicological emergencies are reviewed, with discussion of pharmacists' role in ensuring their ready availability and proper use.

SUMMARY

Poisoning is the second leading cause of injury-related morbidity and mortality in the United States, with more than 2.4 million toxic exposures reported each year. Recently published national consensus guidelines recommend that hospitals providing emergency care routinely stock 24 antidotes for a wide range of toxicities, including toxic-alcohol poisoning, exposure to cyanide and other industrial agents, and intentional or unintentional overdoses of prescription medications (e.g., calcium-channel blockers, β-blockers, digoxin, isoniazid). Pharmacists can help reduce morbidity and mortality due to poisonings and overdoses by (1) recognizing the signs and symptoms of various types of toxic exposure, (2) guiding emergency room staff on the appropriate use of antidotes and supportive therapies, (3) helping to ensure appropriate monitoring of patients for antidote response and adverse effects, and (4) managing the procurement and stocking of antidotes to ensure their timely availability.

CONCLUSION

Pharmacists can play a key role in reducing poisoning and overdose injuries and deaths by assisting in the early recognition of toxic exposures and guiding emergency personnel on the proper storage, selection, and use of antidotal therapies.

Methanol may function as a cross-kingdom signal

Recently, we demonstrated that leaf wounding results in the synthesis of pectin methylesterase (PME), which causes the plant to release methanol into the air. Methanol emitted by a wounded plant increases the accumulation of methanol-inducible gene mRNA and enhances antibacterial resistance as well as cell-to-cell communication, which facilitates virus spreading in neighboring plants. We concluded that methanol is a signaling molecule involved in within-plant and plant-to-plant communication. Methanol is considered to be a poison in humans because of the alcohol dehydrogenase (ADH)-mediated conversion of methanol into toxic formaldehyde. However, recent data showed that methanol is a natural compound in normal, healthy humans. These data call into question whether human methanol is a metabolic waste product or whether methanol has specific function in humans.

Here, to reveal human methanol-responsive genes (MRGs), we used suppression subtractive hybridization cDNA libraries of HeLa cells lacking ADH and exposed to methanol. This design allowed us to exclude genes involved in formaldehyde and formic acid detoxification from our analysis. We identified MRGs and revealed a correlation between increases in methanol content in the plasma and changes in human leukocyte MRG mRNA levels after fresh salad consumption by volunteers. Subsequently, we showed that the methanol generated by the pectin/PME complex in the gastrointestinal tract of mice induces the up- and downregulation of brain MRG mRNA. We used an adapted Y-maze to measure the locomotor behavior of the mice while breathing wounded plant vapors in two-choice assays. We showed that mice prefer the odor of methanol to other plant volatiles and that methanol changed MRG mRNA accumulation in the mouse brain.

We hypothesize that the methanol emitted by wounded plants may have a role in plant-animal signaling. The known positive effect of plant food intake on human health suggests a role for physiological methanol in human gene regulation.

Hyperglycemia is a strong prognostic factor of lethality in methanol poisoning

Methanol poisoning is seen in the form of isolated episodes, or intentional ingestion and epidemics. Despite its efficient treatment, methanol poisoning has high morbidity and mortality rates. So far, several studies have been performed to identify the prognostic factors in methanol poisoning. Recently, during the treatment of patients with methanol poisoning, we observed that patients' blood glucose levels were high on presentation to the hospital, particularly in those who expired. Through a literature search, we found that no studies have been performed on blood glucose levels or hyperglycemia in methanol poisoning. Therefore, the present retrospective study was done as a preliminary investigation to understand whether there was a meaningful relationship between methanol poisoning and blood glucose level on presentation, and also if hyperglycemia could be considered as a prognostic factor for mortality. In this retrospective study, a review of the hospital charts was performed for all patients who were treated for methanol poisoning from March 2003 to March 2010 in two hospitals in Tehran, Iran. Those with definitive diagnosis of methanol poisoning, no history of diabetes mellitus, and normal or low body mass index (<25) were included. Patients' demographic information, clinical manifestations, time elapsed between ingestion and presentation, blood glucose level on presentation (before treatment), results of arterial blood gas analysis, and the clinical outcome were recorded. Statistical analysis was done using SPSS software (version 17, Chicago, Illinois, USA) and application of Mann-Whitney U test, Pearson's chi-square test, Pearson correlation coefficient (r), receiver operating characteristic (ROC) curve, and logistic regression. P values less than 0.05 were considered as the statistically significant levels. Ninety-five patients with methanol poisoning met the inclusion criteria and were included in the study. Of these, 91 (96%) were male and 4 (4%) were female. Mean age was 31.61 ± 14.3 years (range, 13 to 75). Among the 95 patients, 68 survived (72%) and 27 expired (28%). Median blood glucose level was 144 mg/dL (range, 75 to 500). There was no significant statistical correlation between blood glucose level and time of treatment, age, pCO(2), or serum bicarbonate concentration, but blood glucose level had a statistically significant correlation with pH (r = -0.242, P = 0.02) and base deficit (r = 0.230, P = 0.03). The mean blood glucose level was 140 ± 55 and 219 ± 99 mg/dL in the survivor and non-survivor patients, respectively (P < 001). Considering the cutoff level of 140 mg/dL for blood glucose and using logistic regression analysis, and adjusting according to the admission data with significant statistical difference in the two study groups, the odds ratio for hyperglycemia as a risk factor for death was 6.5 (95% confidence interval = 1.59-26.4). Our study showed that blood glucose levels were high in methanol poisoning and even higher in those who died in comparison with the survivors. Therefore, hyperglycemia might be a new prognostic factor in methanol poisoning, but further studies are needed to determine whether controlling hyperglycemia has therapeutic consequences.

Elevated formic acid concentrations in putrefied post-mortem blood and urine samples

Formic acid (FA) concentration was measured in post-mortem blood and urine samples as methyl formate using a headspace in-tube extraction gas-chromatography-mass-spectrometry method. A total of 113 cases were analyzed, each including a blood and urine sample fortified with 1% sodium fluoride. The cases were divided into three groups: regular (n=59), putrefied (n=30), and methanol-positive (n=22) cases. There was no evidence of ante-mortem methanol consumption in the regular and putrefied cases. In regular cases, the mean (and median) FA concentrations were 0.04 g/l (0.04 g/l) and 0.06 g/l (0.04 g/l) in blood and urine, respectively. In putrefied cases, the mean (and median) FA concentrations were substantially higher, 0.24 g/l (0.22 g/l) and 0.25 g/l (0.15 g/l) in blood and urine, respectively. In three putrefied cases, FA concentration in blood exceeded 0.5 g/l, a level associated with fatal methanol poisoning. Ten putrefied cases were reanalyzed after 3-4 months storage, and no significant changes in FA concentrations were seen. These observations suggest that FA was formed by putrefaction during the post-mortem period, not during sample storage when sodium fluoride was added as a preservative. In methanol-positive cases, the mean (and median) FA concentrations were 0.80 g/l (0.88 g/l) and 3.4 g/l (3.3 g/l) in blood and urine, respectively, and the concentrations ranged from 0.19 to 1.0 g/l in blood and from 1.7 to 5.6 g/l in urine. The mean (and median) methanol concentrations in methanol-positive cases were 3.0 g/l (3.0 g/l) and 4.4 g/l (4.7 g/l) in blood and in urine, respectively. The highest methanol concentrations were 6.0 g/l and 8.7 g/l in blood and urine, respectively. No ethyl alcohol was found in the methanol-positive blood samples. Poor correlation was shown between blood and urine concentrations of FA. Poor correlations were also shown, in both blood and urine, between methanol and FA concentrations.

Treatment of patients with ethylene glycol or methanol poisoning: focus on fomepizole

Ethylene glycol (EG) and methanol are responsible for life-threatening poisonings. Fomepizole, a potent alcohol dehydrogenase (ADH) inhibitor, is an efficient and safe antidote that prevents or reduces toxic EG and methanol metabolism. Although no study has compared its efficacy with ethanol, fomepizole is recommended as a first-line antidote. Treatment should be started as soon as possible, based on history and initial findings including anion gap metabolic acidosis, while awaiting measurement of alcohol concentration. Administration is easy (15 mg/kg-loading dose, either intravenously or orally, independent of alcohol concentration, followed by intermittent 10 mg/kg-doses every 12 hours until alcohol concentrations are <30 mg/dL). There is no need to monitor fomepizole concentrations. Administered early, fomepizole prevents EG-related renal failure and methanol-related visual and neurological injuries. When administered prior to the onset of significant acidosis or organ injury, fomepizole may obviate the need for hemodialysis. When dialysis is indicated, 1 mg/kg/h-continuous infusion should be provided to compensate for its elimination. Side-effects are rarely serious and with a lower occurrence than ethanol. Fomepizole is contraindicated in case of allergy to pyrazoles. It is both efficacious and safe in the pediatric population, but is not recommended during pregnancy. In conclusion, fomepizole is an effective and safe first-line antidote for EG and methanol intoxications.

Use of the osmolal gap to guide the start and duration of dialysis in methanol poisoning

OBJECTIVE

Rapid diagnosis and treatment of methanol poisoning is mandatory. Dependence on serum methanol analysis in this situation may delay diagnosis and treatment. The anion and osmolal gaps have been recommended for use as diagnostic tools, but the use of these gaps to evaluate the length of hemodialysis treatment has only been emphasized in a few reports. We evaluated the usefulness of the osmolal gap in estimating the need for dialysis and the duration of this treatment in 17 methanol-poisoned subjects.

MATERIAL AND METHODS

Patients were part of a recent outbreak of methanol poisoning, in which the diagnosis upon admission was mainly based on use of the anion and osmolal gaps. The duration of dialysis generally followed the standard recommendation of 8h. During dialysis, blood samples were frequently collected and analyzed to determine acid-base status and serum methanol and to calculate the osmolal gap. In nine patients, the duration of dialysis was compared with the duration necessary to normalize serum methanol and the osmolal gap.

RESULTS

There was a good correlation between serum methanol and the osmolal gap during hemodialysis (y=1.09x+3.82; R(2)=0.92). The osmolal gap therefore gives a good estimate of the serum methanol level during hemodialysis, and could have saved a total of 23 h of dialysis treatment (34%) in nine patients had it been applied.

CONCLUSIONS

In the absence of serum methanol analyses, the osmolal gap is useful to assess the indication for and duration of hemodialysis in methanol-poisoned patients. In mass poisoning situations, use of the osmolal gap makes it possible to reduce the duration of dialysis in a safe manner.

How good are clinical chemistry laboratories at analysing ethylene glycol?

The results of an external proficiency test of clinical chemistry laboratories in Sweden when the target analyte was ethylene glycol (EG) are presented. Specimens of plasma were spiked with EG (10% w/v) to give assigned concentrations ranging from 5 to 50 mmol/L. Over a period of 6 years, two control specimens of plasma were sent for analysis on 21 occasions to between 14 and 20 participating laboratories as a declared proficiency trial. The analytical precision between and within laboratories was determined by spiking the plasma specimens with the same concentration of EG so that the results reported back could be considered a duplicate determination. On one occasion propylene glycol (PG) was substituted for EG without informing the participants. The standard deviation (SD) within laboratories expressed as the coefficient of variation (CV) was 4.5% compared with 11.4% between laboratories. Results reported by laboratories using gas chromatography (GC) were in good agreement with those when an enzymatic method was used. The between-laboratory SD increased with concentration of EG in the specimen and at a mean concentration of 18 mmol/L, the pooled SD was 4.11 mmol/L (CV = 23%). Four laboratories reported finding EG in plasma when PG was the diol present; three laboratories used an enzymatic method and one used GC. Clinical laboratories that provide a toxicology service should regularly participate in external quality assurance schemes that include low-molecular-weight alcohols such as EG. Efforts should be made to standardize the analytical methods used for toxicological analysis.

The value of brain CT findings in acute methanol toxicity

OBJECTIVE

Due to depressant effects of methanol on the central nervous system, brain computed tomography (CT) scan has been introduced as a diagnostic device in methanol intoxication. The authors aimed to present brain CT findings in patients with acute methanol intoxication and to determine signs associated with death.

MATERIALS AND METHODS

This cohort study involved 42 consecutive patients with acute methanol intoxication. Inclusion criteria were consisted of characteristic clinical presentation of methanol poisoning, and metabolic acidosis with increased anion and osmolar gaps. Brain CT scans without contrast medium were obtained. To determine the association between the CT findings and death, the chi-square test or the Fisher's exact test, odds ratio (OR) and its 95% confidence interval (95% CI) were calculated.

RESULTS

Twenty-eight patients (66.6%) had a total of 55 abnormal findings on brain CT, in which bilateral putaminal hypodense lesions was the most common manifestation (27 cases, 96.4%). Putaminal hemorrhage with varying degrees was observed in 7 patients (25%). Six patients (21.4%) had low attenuation lesions in the subcortical white matter of the insula. A significant association was observed between putaminal hemorrhage (OR=8, 95% CI=1.187-53.93, P=0.018) and subcortical necrosis of the insula (OR=11, 95% CI=1.504-80.426, P=0.007) with death.

CONCLUSION

In addition to clinical and laboratory findings, presence of putaminal hemorrhage and insular subcortex white matter necrosis are associated with a poor clinical outcome in patients with methanol poisoning.

Expert opinion: fomepizole may ameliorate the need for hemodialysis in methanol poisoning

Fomepizole is now the antidote of choice in methanol poisoning. The use of fomepizole may also change the indications for hemodialysis in these patients. We have addressed this change in a review of articles on methanol poisonings. Review of the literature (through PubMed) combined with our own experiences from two recent methanol outbreaks in Estonia and Norway. The efficiency of dialysis during fomepizole treatment was reported in only a few reports. One recent study challenged the old indications, suggesting a new approach with delayed or even no hemodialysis. Methanol-poisoned patients on fomepizole treatment may be separated into two categories: 1) The critically ill patient, with severe metabolic acidosis (base deficit >15 mM) and/or visual disturbances should be given buffer, fomepizole and immediate hemodialysis: dialysis removes the toxic anion formate, and assists in correcting the metabolic acidosis, thereby also reducing formate toxicity. The removal of methanol per se is not important in this setting because fomepizole prevents further production of formic acid. 2) The stable patient, with less metabolic acidosis and no visual disturbances, should be given buffer and fomepizole. This treatment allows for the possibility to delay, or even drop, dialysis in this setting, because patients will not develop more clinical features from methanol poisoning when fomepizole and bicarbonate is given in adequate doses. Indications and triage for hemodialysis in methanol poisonings should be modified. Delayed hemodialysis or even no hemodialysis may be an option in selected cases.

Toxic alcohol ingestions: clinical features, diagnosis, and management

Alcohol-related intoxications, including methanol, ethylene glycol, diethylene glycol, and propylene glycol, and alcoholic ketoacidosis can present with a high anion gap metabolic acidosis and increased serum osmolal gap, whereas isopropanol intoxication presents with hyperosmolality alone. The effects of these substances, except for isopropanol and possibly alcoholic ketoacidosis, are due to their metabolites, which can cause metabolic acidosis and cellular dysfunction. Accumulation of the alcohols in the blood can cause an increment in the osmolality, and accumulation of their metabolites can cause an increase in the anion gap and a decrease in serum bicarbonate concentration. The presence of both laboratory abnormalities concurrently is an important diagnostic clue, although either can be absent, depending on the time after exposure when blood is sampled. In addition to metabolic acidosis, acute renal failure and neurologic disease can occur in some of the intoxications. Dialysis to remove the unmetabolized alcohol and possibly the organic acid anion can be helpful in treatment of several of the alcohol-related intoxications. Administration of fomepizole or ethanol to inhibit alcohol dehydrogenase, a critical enzyme in metabolism of the alcohols, is beneficial in treatment of ethylene glycol and methanol intoxication and possibly diethylene glycol and propylene glycol intoxication. Given the potentially high morbidity and mortality of these intoxications, it is important for the clinician to have a high degree of suspicion for these disorders in cases of high anion gap metabolic acidosis, acute renal failure, or unexplained neurologic disease so that treatment can be initiated early.