Methanol and ethylene glycol intoxication

Intracerebral hemorrhage in methanol toxicity patients during COVID-19 pandemic: case report and review of literature

PURPOSE

The aim of this study is to examine the clinical and imaging manifestations of methanol toxicity during the COVID-19 pandemic, as well as to review existing studies on this topic. The most common cause of methanol intoxication is methanol-adulterated liquor. The primary metabolite of methanol, formic acid, is responsible for pathological changes. Symptoms typically present within 6-24 h of consumption and can include visual disturbances, acute neurological symptoms, and gastrointestinal issues. During the initial year of the COVID-19 pandemic, methanol poisoning cases increased significantly.

METHODS

In this study, We present six different patients with methanol intoxication and their clinical and imaging features.

RESULTS

In the literature review, the most common clinical presentation was loss of consciousness and obtundation and the other was vision loss. CT scan findings showed bilateral putaminal necrosis and hemorrhage in 55% of methanol toxicity patients.

CONCLUSION

Methanol intoxication, causing bilateral putaminal involvement and a 50% mortality rate in intracerebral hemorrhage patients, warrants urgent toxicological analysis due to potential putaminal hemorrhage.

When Vaping Isn't Actually Safer: A Death From Toxic Alcohol Contaminated Vape Juice

ABSTRACT

Vape juice is a diluent for e-cigarette active ingredients, nicotine or tetrahydrocannabinol (THC). Lack of strict regulation in vape juice production is a concern as ingredients and their concentrations may vary widely from the labeling.A 43-year-old woman was transported via ambulance to the hospital after ingesting homemade vape juice, presenting unresponsive with decerebrate posturing. She reportedly made a tincture combining a vape juice purchased online (containing "ethylene glycol") and THC for "endometriosis-related pain relief." Laboratory evaluation revealed anion gap metabolic acidosis, elevated serum lactate, and high serum osmolality. Urine fluoresced under Wood's lamp, and fomepizole was administered as an ethylene glycol antidote, but she expired the following afternoon. Clinical serum toxicology results returned after death revealed 235 mg/dL of methanol, and no ethylene glycol.Autopsy findings included ischemic changes of the gastrointestinal tract and cerebral edema with herniation. Postmortem toxicology performed on hospital admission blood revealed methanol (220 mg/dL), propylene glycol (59 mg/dL), Δ-9 THC and metabolites, and medications administered during hospitalization. The medical examiner determined the cause of death to be methanol and propylene glycol toxicity.To our knowledge, this is the first report of accidental death from ingestion of vape juice contaminated with toxic alcohol.

Clinical presentation and management of methanol poisoning outbreaks in Riyadh, Saudi Arabia: a retrospective analysis

BACKGROUND

Acute methanol intoxication, whether unintentional or deliberate, necessitates prompt intervention to prevent severe morbidity and mortality. Homemade alcoholic beverages are a frequent source of such poisoning. This retrospective analysis examined two outbreaks of methanol intoxication in Saudi Arabia. It investigated the clinical presentation, implemented management strategies, and any lasting complications (sequelae) associated with these cases. The aim was to assess the potential impact of different treatment modalities and the timeliness of their initiation on patient outcomes.

METHODS

This was a retrospective case series of methanol poisoning cases which presented to the adult emergency department (ED) at King Abdulaziz Medical City (KAMC) in Riyadh, Saudi Arabia. There were two separate outbreaks in the city, the first one was from September 1 to September 10, 2020 and the second one was from May 14 to May 20, 2021. Electronic charts were reviewed, and data were extracted to previously prepared data extraction sheets.

RESULT

From the 22 patients who arrived in the ED alive, the most common complaints were nausea or vomiting followed by altered level of consciousness. About 9% from the patient were hypotensive, 36% were tachycardic, 41% were tachypneic and 4% were having SpO2 < 94%. Brain CT was abnormal in 6 patients. Vision impairment was the most common sequalae of methanol poisoning (7 out of 12 patients who were assessed by ophthalmologist, 58%). When the patients were divided based on severity (mild, moderate, severe), nausea or vomiting and loss of consciousness were the most common complaints among the moderate group while loss of consciousness predominated in the severe group. Two patients presented with low blood pressure and were in the sever group. The severe group had a mean Glasgow Coma Scale (GCS) of 8. Most of the patients in the severity groups underwent the same management apart from those who died or deposited. Eight patients in the severe group had to be intubated.

CONCLUSION

This study demonstrates the multifaceted clinical presentation of methanol poisoning, culminating in a 17.4% mortality rate. Notably, our findings emphasize the critical role of prompt diagnosis and swift initiation of combined fomepizole therapy and hemodialysis in mitigating mortality and minimizing the potential for chronic visual sequelae associated with methanol poisoning.

Combined Ethylene Glycol Poisoning with Methemoglobinemia Due to Antifreeze Ingestion

BACKGROUND

Antifreeze poisoning is potentially life-threatening and often requires multiple antidotal therapies and hemodialysis. Ethylene or propylene glycol toxicity is commonly caused by antifreeze ingestion. However, ingestion of antifreeze is typically not associated with methemoglobinemia. Currently, only one other case of antifreeze ingestion causing combined ethylene glycol poisoning and methemoglobinemia has been reported.

CASE REPORT

A 56-year-old man presented after a witnessed, intentional, large-volume antifreeze ingestion. Evaluation revealed dark brown blood and significantly elevated methemoglobin and ethylene glycol levels. He was successfully treated with methylene blue, fomepizole, and hemodialysis. No other potential cause for methemoglobinemia was elucidated, and further research indicated that minor components of the specific antifreeze product served as an oxidizing agent. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This case highlights the impact of minor, unreported product components that may significantly contribute to clinical toxicity, as well as the need to remain vigilant when reviewing product information and potential limitations therein.

Acute Kidney Injury with Hyperlactatemia: Clues to a Hidden Problem

N/a.

High risk and low prevalence diseases: Toxic alcohol ingestion

INTRODUCTION

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

OBJECTIVE

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

DISCUSSION

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

CONCLUSIONS

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

Nanosensor Based on Thermal Gradient and Machine Learning for the Detection of Methanol Adulteration in Alcoholic Beverages and Methanol Poisoning

Methanol, naturally present in small quantities in the distillation of alcoholic beverages, can lead to serious health problems. When it exceeds a certain concentration, it causes blindness, organ failure, and even death if not recognized in time. Analytical techniques such as chromatography are used to detect dangerous concentrations of methanol, which are very accurate but also expensive, cumbersome, and time-consuming. Therefore, a gas sensor that is inexpensive and portable and capable of distinguishing methanol from ethanol would be very useful. Here, we present a resistive gas sensor, based on tin oxide nanowires, that works in a thermal gradient. By combining responses at various temperatures and using machine learning algorithms (PCA, SVM, LDA), the device can distinguish methanol from ethanol in a wide range of concentrations (1–100 ppm) in both dry air and under different humidity conditions (25–75% RH). The proposed sensor, which is small and inexpensive, demonstrates the ability to distinguish methanol from ethanol at different concentrations and could be developed both to detect the adulteration of alcoholic beverages and to quickly recognize methanol poisoning.

Methanol poisoning in the emergency department: a retrospective study

Aim: Massive methanol poisonings have occurred in the past decades, resulting in a large number of deaths. In this study, our aim is to retrospectively analyze methanol poisoning cases admitted to the emergency department between 2019-2021, to evaluate their demographic characteristics, causes of poisoning, clinical and laboratory findings, treatments applied and mortality, and to contribute to the poisoning data of our country. Material and Method: The cases of methanol poisoning who applied to the emergency department in a 3-year period were analyzed retrospectively. Medical files of patients aged 18 years and older were reviewed. Patients diagnosed with 'methanol poisoning' as a result of the examination were included in the study. Results: A total of 59 patients were included in the study. 88% (n=52) of the patients with a mean age of 53±10 were male. The presence of neurological symptoms and GCS were associated with mortality among the symptoms of patients presenting to the emergency department (p=0.017, p

Ethylene glycol toxicosis in milk-fed dairy calves

BACKGROUND

Ethylene glycol (EG) (antifreeze) toxicosis has mostly been reported in dogs and cats, while reports on EG toxicosis in cattle are sparse. We report EG toxicosis in 25 milk-fed calves associated with a leak in the cooling pipes in a milk taxi. The milk taxi was connected to a geothermal heating system in which EG was used as antifreeze.

CASE PRESENTATION

Although the assistant responsible for feeding milk to the calves observed a few blue-colored droplets of liquid on the surface of the milk in the milk taxi and suspected EG contamination, the milk was fed to the calves. Within hours, the calves became depressed and some died within the next 2 days. Necropsy and histopathology revealed widespread severe acute renal tubular necrosis with numerous birefringent crystals in the tubular lumen. Biochemical analysis of serum showed severe damage to the kidneys (marked azotemia) and hypochloremia, hyponatremia and hyperkalemia; findings consisting with metabolic acidosis. After feeding the calves, the assistant inspected the milk taxi and found a leaking cooling pipe.

CONCLUSIONS

The suspected EG toxicosis was confirmed by the observation of renal tubular necrosis, numerous intratubular crystals, and metabolic acidosis. EG toxicosis due to leaking pipes connected to a geothermal heating system has not been reported previously. Alternative antifreeze products that are less toxic than EG are recommended for use if there is a risk of contamination of human and animal foodstuffs in case of a leak in the system.

Toxic and Nutritional Optic Neuropathies—An Updated Mini-Review

Optic neuropathies constitute a group of conditions with various etiologies and might be caused by different factors; we can distinguish the genetic and acquired causes of optic neuropathies. Even though the symptoms are not highly specific, this condition is primarily characterized by unilateral or bilateral vision loss with worsening color detection. The loss may be acute or gradual depending on the causation. In this article, we included a specification of toxic optic neuropathy (TON) mainly triggered by alcohol abuse and also the usage of other substances, including drugs or methanol, as well as intoxication by metals, organic solvents, or carbon dioxide. Nutritional deficiencies, vitamin absorption disorder, and anemia, which usually appear during excessive alcohol intake, and their effect on the etiology of the optic neuropathy have been likewise discussed.

Oxalate nephropathy: a review

This review describes the clinical and pathological features of oxalate nephropathy (ON), defined as a syndrome of decreased renal function associated with deposition of calcium oxalate crystals in kidney tubules. We review the different causes of hyperoxaluria, including primary hyperoxaluria, enteric hyperoxaluria and ingestion-related hyperoxaluria. Recent case series of biopsy-proven ON are reviewed in detail, as well as the implications of these series. The possibility of antibiotic use predisposing to ON is discussed. Therapies for hyperoxaluria and ON are reviewed with an emphasis on newer treatments available and in development. Promising research avenues to explore in this area are discussed.

Fluorometric trace methanol detection in ethanol and isopropanol in a water medium for application in alcoholic beverages and hand sanitizers

Detection of methanol (MeOH) in an ethanol (EtOH)/isopropanol (ⁱPrOH) medium containing water is crucial to recognize MeOH poisoning in alcoholic beverages and hand sanitizers. Although chemical sensing methods are very sensitive and easy to perform, the chemical similarities between the alcohols make MeOH detection very challenging particularly in the presence of water. Herein, the fluorometric detection of a trace amount of MeOH in EtOH/ⁱPrOH in the presence of water using alcohol coordinated Al(iii)-complexes of an aldehydic phenol ligand containing a dangling pyrazole unit is described. The presence of MeOH in the EtOH/ⁱPrOH causes a change of the complex geometry from tetrahedral (Td) to octahedral (Oh) due to the replacement of the coordinated EtOH/ⁱPrOH by MeOH molecules. The Td-complex exhibited fluorescence but the Oh-species did not, because of the intramolecular photo-induced electron transfer (PET). By interacting the Oh species with water, its one MeOH coordination is replaced by a water molecule followed by the proton transfer from the water to pyrazole-N which generates strong fluorescence by inhibiting the PET. In contrast, the water interaction dissociates the Td-complex to exhibit fluorescence quenching. The water induced reversal of the fluorescence response from the decrease to increase between the absence and presence of MeOH is utilized to detect MeOH in an EtOH/ⁱPrOH medium containing water with a sensitivity of ∼0.03–0.06% (v/v). The presence of water effected the MeOH detection and allows the estimation of the MeOH contamination in alcoholic beverages and hand sanitizers containing large amounts of water.

Detection of MeOH in EtOH/ⁱPrOH and commercial samples based on water induced reversal of fluorescence response from the decrease to increase between the absence and presence of MeOH.

Alcohol and the Risk of Injury

Globally, almost four and a half million people died from injury in 2019. Alcohol's contribution to injury-related premature loss of life, disability and ill-health is pervasive, touching individuals, families and societies throughout the world. We conducted a review of research evidence for alcohol's causal role in injury by focusing on previously published systematic reviews, meta-analyses and where indicated, key studies. The review summarises evidence for pharmacological and physiological effects that support postulated causal pathways, highlights findings and knowledge gaps relevant to specific forms of injury (i.e., violence, suicide and self-harm, road injury, falls, burns, workplace injuries) and lays out options for evidence-based prevention.

Investigating the epidemiology of methanol poisoning outbreaks: a scoping review protocol

OBJECTIVE

We aim to identify relevant studies from 2000 to 2020 regarding methanol poisoning outbreaks and map the existing literature with a focus on the epidemiology and global burden of disease.

INTRODUCTION

Methanol poisoning occurs in individuals or as an outbreak. Illicit productions are responsible for most methanol poisoning outbreaks; however, there are some occupational, suicidal, and homicidal incidences as well. In methanol poisoning outbreaks, medical facilities get overwhelmed quickly. The current WHO fact sheet dates back to 2014 and there have been no updates since. Based on our preliminary search, it seems that the course of methanol outbreaks has changed.

INCLUSION CRITERIA

The study will include peer-reviewed articles and gray papers that focus on the epidemiology of methanol poisoning outbreaks. This review will consider all methanol poisoning outbreak victims without any limitation in geographical, social, cultural, or gender-based demographics.

METHODS

A three-step search strategy will be used. First, an initial search will be done in MEDLINE and Scopus to identify key terms. Those key terms will then be searched across included databases (MEDLINE, Scopus, Embase, and Web of Science) and sources for gray literature. In a third step, references and Google Scholar will be searched manually. Two reviewers will screen the titles and abstracts, then full texts for identifying inclusion criteria and data extraction. Disagreements will be resolved by a senior author. Extracted data will be tabulated and mapped. Quantitative data will be reported using descriptive numerical summary analysis.

The antiurolithic activity of Origanum vulgare on rats treated with ethylene glycol and ammonium chloride: Possible pharmaco-biochemical and ultrastructure effects

Background:

Origanum vulgare (OV) Linn is one of the conventional remedies for urolithiasis. Hence, we tested the potential antiurolithic effect of OV active extract, in order to rationalize its medicinal use.

Materials and methods:

The in vivo study was of male Westar rats receiving lithogenic treatment consisting of two 0.75% ethylene glycol injections with a 1 day interval and then in drinking water given for 3 weeks along with ammonium chloride (NH₄Cl) from the 2nd day to the 7th day.

Results:

The active ethanolic extract of OV treatment (20 mg/kg) reversed toxic changes including loss of body weight gain and appetite, raised serum urea and creatinine levels, and raised blood pressure compared to controls.

Conclusions:

The acquired data thus suggested that OV showed antiurolithic effects against renal calcium oxalate crystal deposits by combined mechanisms acting on multiple sites through hypoxaliuric, hypocalciuric, and antioxidant effects.

[Effect of stiripentol on urine oxalate excretion]

Oxalate is a metabolite promoting the formation of calcium oxalate crystals in urine. Hyperoxaluria is a feature of genetic diseases, known as primary hyperoxaluria, leading to chronic kidney disease. Ethylene glycol poisoning induces the crystallization of calcium oxalate crystals in renal tubules, promoting acute renal failure. Urine oxalate results from glyoxylate transformation to oxalate in the liver, due to lactate dehydrogenase (LDH) activity, especially the LDH-5 isoenzyme. Genetic RNA interference therapy targeting lactate dehydrogenase lowers urine oxalate excretion in murine models. Stiripentol is a drug inhibiting neuronal LDH-5 isoenzyme activity. We hypothesized that stiripentol would also reduce hepatic oxalate production and urine oxalate excretion. In vitro Stiripentol decreases oxalate synthesis by hepatocytes. In vivo, stiripentol decreases urine oxalate excretion in rats and protects kidney tissue and function against ethylene glycol intoxication and hydroxyproline-induced calcium oxalate crystalline nephropathy. The use of stiripentol in clinical practice deserves further clinical studies.

Chronic exposure of industrial grade calcium carbide and ethylene glycol alter histological architecture of systemic organs by disrupting redox balance in rat

OBJECTIVES

The threat to human health or the surroundings by the use of artificial fruit ripening agents has become a global concern. Calcium carbide (CaC₂) and ethylene glycol (EG) are the two widely using ripening agents. The present study evaluates the toxic effect of chronic exposures of CaC₂ and EG in rats.

METHODS

CaC₂ and EG were administered to the rats for 180 days orally. The alterations in oxido-reduction status, haematological, biochemical and histopathological parameters were analysed. Arsenic content in CaC₂ and animal samples were detected by atomic absorption spectrometer and phosphorus by molybdate-UV method.

RESULTS

At chronic doses, there were no significant alterations in haematological and biochemical parameters except in creatinine level especially by EG. However, histological details revealed microvesicular fatty change in liver, corpuscles degeneration in kidney and lymphocytes infiltration in various tissues. In intestine, the mucosal lesion scoring was found high (p<0.01). SOD and CAT activities and GSH level was reduced significantly by CaC₂ administration (p<0.01). Arsenic and phosphorus detected is above the toxic level: 7.222 and 13.91 mg/dL in CaC₂, 1.634 and 6.22 mg/dL in blood and 0.563 and 6.99 mg/dL in liver, respectively.

CONCLUSIONS

The study suggests that the industrial grade CaC₂ and EG induce systemic toxicity to rats and the liver is the most susceptible organ. The CaC₂ and EG toxicity is mediated through the upset of redox balance and subsequent inflammatory responses. This could be due to the presence of arsenic and phosphorus contents that detected above the normal level in the industrial grade CaC₂.

Acute kidney injury in hospitalized patients with methanol intoxication: National Inpatient Sample 2003-2014

BACKGROUND

This study aimed to 1) determine the incidence of acute kidney injury (AKI), 2) identify risk factors for AKI, and 3) evaluate the impact of AKI on in-hospital outcomes in hospitalized patients for methanol intoxication.

METHODS

We searched the National Inpatient Sample Database for hospitalized patients from 2003 to 2014 with a primary diagnosis of methanol intoxication. We excluded patients with end-stage kidney disease. We identified the AKI using a discharge diagnosis code. We compared clinical characteristics, in-hospital treatment, outcomes, and resource use between AKI and non-AKI patients.

RESULTS

A total of 603 hospital admissions for methanol intoxication were analyzed. AKI developed in 135 (22.4%) admissions. Anemia (OR 3.43 p < 0.001), hypertension (OR 1.86; p = 0.02), volume depletion (OR 3.46; p = 0.001), sepsis (OR 6.91; p < 0.001), rhabdomyolysis (OR 6.25; p = 0.003), and acute pancreatitis (OR 5.30; p = 0.004) were independent risk factors for AKI development. AKI was significantly associated with increased risk of in-hospital mortality and organ failure. AKI patients needed more mechanical ventilation, and extracorporeal therapy, had longer length of hospital stay, and higher hospitalization costs.

CONCLUSION

Over one-fifth of methanol intoxication patients developed AKI during hospitalization. AKI was associated with higher morbidity, mortality, and resource utilization.

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.

Stiripentol identifies a therapeutic target to reduce oxaluria

PURPOSE OF REVIEW

Oxalate is a metabolic end-product promoting the formation of calcium oxalate crystals in urine. Massive urine oxalate excretion occurs in genetic diseases, mainly primary hyperoxaluria type I and II, threatening renal function. Ethylene glycol poisoning may induce the precipitation of calcium oxalate crystals in renal tubules, leading to acute renal failure. In both cases, oxalate results from glyoxylate transformation to oxalate in the liver, by lactate dehydrogenase (LDH) enzymes, especially the LDH-5 isoenzyme. The purpose of the review is to highlight LDH as a potential therapeutic target according to recent publications.

RECENT FINDINGS

Genetic therapy targeting LDH metabolism decreases urine oxalate excretion in rodents. Stiripentol is an antiepileptic drug that has been shown recently to inhibit neuronal LDH-5 isoenzyme. Stiripentol was hypothesized to reduce hepatic oxalate production and urine oxalate excretion. In vitro, stiripentol decreases oxalate synthesis by hepatocytes. In vivo, stiripentol oral administration decreases urine oxalate excretion in rats and protects renal function and renal tissue against ethylene glycol intoxication and chronic calcium oxalate crystalline nephropathy.

SUMMARY

The use of stiripentol in-vitro and in-vivo highlights that targeting hepatic LDH by pharmacological or genetic tools may decrease oxalate synthesis, deserving clinical studies.

A new imidazole based phenanthridine probe for ratiometric fluorescence monitoring of methanol in biodiesel

We prepared and characterized an array of polarity-sensitive fluorescent dyes (7and 9a, 9b and 9c). for detection of methanol

Oral Ethanol Treatment for Ethylene Glycol Intoxication

Ethylene glycol is an odorless, sweet-tasting liquid found in industrial solutions such as antifreeze and windshield wiper fluid. Brake fluid, an automobile transmission liquid, contains poisonous alcohols such as glycol ethers and ethylene glycols. The toxicity of ethylene glycol is associated with toxic metabolite production by the liver enzyme alcohol dehydrogenase. Administration of either intravenous ethanol or fomepizole, both of which competitively inhibit ethylene glycol metabolism by alcohol dehydrogenase and can prevent the production and accumulation of the toxic metabolites, can be used as an antidote. A 42-year-old male car mechanic was transferred to our hospital after accidentally ingesting approximately 100 mL of brake fluid. Immediately after ingestion, he threw up most of the ingested liquid; however, he complained of nausea and throat pain and was moved to our emergency department. The patient was successfully treated with administration of oral ethanol in the form of whisky through a nasogastric tube since neither intravenous ethanol nor fomepizole was available in our hospital at the time of his presentation. Our case demonstrates that oral ethanol can be used as an alternative treatment for patients with ethylene glycol intoxication.

Unintentional Ethylene Glycol Poisoning in an Adolescent

The differential diagnosis is broad when a patient presents with an altered mental status. Ethylene glycol poisoning, a life-threatening condition, can occur as an intentional self-harm attempt or unintentional consumption. It is metabolized in the liver by a series of enzymes, and the metabolites so formed are responsible for the majority of clinical effects. The diverse range of clinical effects includes central nervous system (CNS), gastrointestinal, cardiovascular system (CVS), pulmonary as well as renal effects. The evidence of metabolic acidosis, elevated anion gap, high osmolal gap, and calcium oxalate crystals in laboratory analysis strongly suggests ethylene glycol poisoning. The treatment traditionally consists of alcohol dehydrogenase inhibitors such as fomepizole or ethanol, and in some cases, hemodialysis is needed as well.

The Toxicity of Secondary Lithium-Sulfur Batteries Components

Currently, apart from the widely known lithium-ion batteries, there are competitive solutions in the form of, for example, Li-S batteries. While the results of studies on the toxicity of Li-ion battery components are published, such studies on the components of Li-S cells are just beginning. The purpose of the current review was to identify materials used in the production of Li-S batteries and their toxicity, especially for humans. The review showed many kinds of materials with different levels of toxicity utilized for manufacturing of these cells. Some materials are of low toxicity, while some others are of the high one. A lot of materials have assigned different hazard statements. For some of the materials, no hazard statements were assigned, although such materials are toxic. No data related to the toxicity of some materials were found in the literature. This points out the need to further studies on their toxicity and legal actions to assign appropriate hazard statements.

Optimization of western blotting for the detection of proteins of different molecular weight

Protein samples electroblotted onto nitrocellulose membranes and quenched with a mixture of blocking agents produced a strong signal for cystic fibrosis transmembrane-conductance regulator (CFTR), a high-molecular-weight protein, in western blotting. Optimized conditions for CFTR were then extended to medium- and low-molecular-weight proteins (LAMP1 and Rab11a, respectively) to determine the effects of methanol concentration (0-20%) in Towbin's transfer buffer (TTB). Methanol in TTB appears to have little to no effect on CFTR signal. However, for medium-sized (LAMP1) and small (Rab11a) proteins, a lower concentration of methanol (10%) was sufficient to produce a maximal signal. Therefore, methanol, a toxic solvent, can be removed from or reduced in TTB without compromising signal strength. Here, we show modifications that may be useful in detecting and/or improving the signal of low-abundance proteins.

Circulating human microRNA biomarkers of oxalic acid-induced acute kidney injury

Oxalic acid-induced nephrotoxicity and acute kidney injury result from formation of calcium oxalate crystals. Oxalic acid-induced acute kidney injury is a significant problem in many parts of the world. Circulating biomarkers that can accurately and reproducibly detect acute kidney injury are highly desirable. We used a high sensitivity discovery platform to identify signature microRNAs to distinguish healthy individuals never exposed to oxalic acid (n = 4) from those who were exposed to oxalic acid but had no injury (NOAKI; n = 4), moderate injury (AKIN2; n = 4) or severe injury (AKIN3; n = 4). Longitudinal analyses identified 4-8 h post-ingestion as the best time to detect AKIN2/3. We validated a signature of 53 microRNAs identified in the discovery, in a second cohort of individuals exposed to oxalic acid (NOAKI = 11, AKIN2 = 8 and AKIN3 = 18) and healthy controls (n = 19). Thirteen microRNAs were significantly downregulated in acute kidney injury patients compared to NOAKI within 8-h post-ingestion. Five microRNAs (miR-20a, miR-92a, miR-93, miR-195, miR-451) had a highly significant correlation with normalized urinary albumin, serum creatinine at 24 h and creatinine clearance. Logistic regression of these microRNAs had AUC-ROC of 0.85 predicting AKIN2/3 and discriminated patients from healthy controls (AUC-ROC = 0.93). mRNA targets of these microRNAs identified oxidative stress pathways of nephrotoxicity in proximal tubule and glomeruli nephrotoxicity. In conclusion, the downregulation of multiple circulating microRNAs in patients correlated with the severity of oxalic acid-induced acute kidney injury. A set of microRNAs (miR-20a, miR-92a, miR-93, miR-195, miR-451) could be promising biomarkers for early detection of oxalic acid-induced acute kidney injury.

Ethylene glycol: Evidence of glucuronidationin vivoshown 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 β‐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.

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.

Time-dependent changes in kidney histopathology in ethylene glycol poisoning

Ethylene glycol (EG) may be acutely toxic following ingestion. In fatal cases, microscopic examination of urine and kidney specimens can establish a post-mortem diagnosis of EG poisoning. We describe the main renal histopathologic changes during different stages of EG poisoning, which might be helpful when dating the EG poisoning itself. A single-centre retrospective study conducted on all EG poisoning cases demonstrated that in an early stage of EG poisoning, fine dust-like crystals were deposited to the tubular cell basement membrane, followed by internalisation of calcium oxalate crystals into the epithelial cells. Later, the crystals formed larger aggregates within the epithelial cells. As the changes became advanced, pronounced tubular epithelial damage occurred, with detachment of epithelial cells from the basement membrane. In the final stage, coarse calcium oxalate crystals were recognised in the tubular lumen, with cellular debris from damaged epithelial cells. Our study shows that the time-dependent histological changes described follow the clinical stages of EG poisoning and may therefore provide a rough estimate of the time of EG ingestion before death.

Clinical use of plasma lactate concentration. Part 1: Physiology, pathophysiology, and measurement

OBJECTIVE

To review the current literature with respect to the physiology, pathophysiology, and measurement of lactate.

DATA SOURCES

Data were sourced from veterinary and human clinical trials, retrospective studies, experimental studies, and review articles. Articles were retrieved without date restrictions and were sourced primarily via PubMed, Scopus, and CAB Abstracts as well as by manual selection.

HUMAN AND VETERINARY DATA SYNTHESIS

Lactate is an important energy storage molecule, the production of which preserves cellular energy production and mitigates the acidosis from ATP hydrolysis. Although the most common cause of hyperlactatemia is inadequate tissue oxygen delivery, hyperlactatemia can, and does occur in the face of apparently adequate oxygen supply. At a cellular level, the pathogenesis of hyperlactatemia varies widely depending on the underlying cause. Microcirculatory dysfunction, mitochondrial dysfunction, and epinephrine-mediated stimulation of Na⁺ -K⁺ -ATPase pumps are likely important contributors to hyperlactatemia in critically ill patients. Ultimately, hyperlactatemia is a marker of altered cellular bioenergetics.

CONCLUSION

The etiology of hyperlactatemia is complex and multifactorial. Understanding the relevant pathophysiology is helpful when characterizing hyperlactatemia in clinical patients.

An unusual case of suicide by methanol ingestion

A female in her late teens purposely ingested alcohol fuel containing methanol to commit suicide, which she admitted on social media. She was found in distress by her parents and died at the hospital some hours later. Autopsy revealed swelling of the brain and edematous and congestive lungs. No other trauma or unusual findings were revealed at autopsy. Methanol was detected upon routine screening for alcohols by headspace gas chromatography with flame-ionization detection. To confirm the presence of methanol and its metabolite formic acid, a method with detection by mass spectrometry was used. Methanol and formic acid were quantitated in body fluids and tissues by headspace gas chromatography with flame-ionization detection. Formic acid was converted to isopropyl formate by reaction with isopropanol and concentrated sulfuric acid. Acetonitrile was used as the internal standard. The methanol and formic acid concentrations were analyzed in peripheral blood, heart blood, cerebrospinal fluid, liver, kidney, spleen, pancreas, lung, muscle, and fat. Successful confirmation and quantitation of methanol and formic acid, a methanol metabolite, in postmortem specimens was achieved on an uncommon case of suicide by methanol ingestion.

Transverse myelitis-like presentation of methanol intoxication: A case report and review of the literature

CONTEXT

Methanol is the simplest member of alcohol family. However, it is an extremely toxic substance to humans upon exposure with severe and detrimental effects that range from visual loss to death. Spinal cord involvement in methanol intoxication is a rare occurrence.

FINDINGS

In this article, we are reporting a case of methanol intoxication with extensive spinal cord involvement possibly due to necrosis. A literature review yielded only two cases of spinal cord involvement due to methanol intoxication. Our article is the first to discuss the spinal cord involvement specifically including interesting neuroimaging features.

CONCLUSION/CLINICAL RELEVANCE

We recommend performing MRI of the cervicothoracic spine in every methanol intoxication case to exclude both asymptomatic and symptomatic cases of spinal cord involvement.

[CME: Ethylene Glycol Intoxication]

CME: Ethylene Glycol Intoxication Abstract. Ethylene glycol is a sweet-tasting alcohol used in common antifreeze and other industrial solutions. Without appropriate therapy, intoxication with ethylene glycol can result in severe metabolic acidosis, acute renal failure, and in death. After gastrointestinal resorption, hepatic metabolism starts with oxidation by alcohol dehydrogenase and results in severe anion gap metabolic acidosis. Other metabolic products are calcium oxalate crystals, which can deposit in several tissues like the kidneys and lead to acute tubular necrosis with reversible renal failure. The crucial therapeutic step is rapid inhibition of alcohol dehydrogenase with fomepizole or ethanol to avoid the formation of toxic metabolites. Additionally, haemodialysis is the most effective way to eliminate ethylene glycol as well as its toxic metabolites. If therapy is initiated rapidly, prognosis is favorable.

Case Report Demonstrating the Safe and Effective Means of Expanding the Donor Pool With Livers Recovered From Brain-Dead Donors After Ethylene Glycol Toxicity

The growing disparity between organ supply and demand has become the greatest hurdle facing transplant professionals and life-saving transplants. Because the organ shortage has become the rate-limiting step to effective transplants, it is critical for the transplant community to identify viable mechanisms to expand the donor pool and use every available allograft. Although using kidneys from deceased donors whose demise was secondary to ethylene glycol (EG) toxicity requires great deliberation and precise timing as described by Barbas et al [5], using hepatic allografts in this setting involves far less risk. The following is a discussion of a 61-year-old male who was diagnosed with end-stage liver disease secondary to non-alcoholic steatohepatitis and ultimately underwent a life-saving transplant with a liver recovered from a donor with EG-induced brain death and allocated nationally due to trepidation by local and regional centers to use the liver from a donor after EG toxicity.

Ethylene Glycol Poisoning: An Unusual Cause of Altered Mental Status and the Lessons Learned from Management of the Disease in the Acute Setting

Ethylene glycol is found in many household products and is a common toxic ingestion. Acute ingestions present with altered sensorium and an osmolal gap. The true toxicity of ethylene glycol is mediated by its metabolites, which are responsible for the increased anion gap metabolic acidosis, renal tubular damage, and crystalluria seen later in ingestions. Early intervention is key; however, diagnosis is often delayed, especially in elderly patients presenting with altered mental status. There are several laboratory tests which can be exploited for the diagnosis, quantification of ingestion, and monitoring of treatment, including the lactate and osmolal gaps. As methods of direct measurement of ethylene glycol are often not readily available, it is important to have a high degree of suspicion based on these indirect laboratory findings. Mainstay of treatment is bicarbonate, fomepizole or ethanol, and, often, hemodialysis. A validated equation can be used to estimate necessary duration of hemodialysis, and even if direct measurements of ethylene glycol are not available, monitoring for the closure of the anion, lactate, and osmolal gaps can guide treatment. We present the case of an elderly male with altered mental status, acute kidney injury, elevated anion gap metabolic acidosis, and profound lactate and osmolal gaps.

Adolescent Presents With Altered Mental Status and Elevated Anion Gap After Suicide Attempt by Ethylene Glycol Ingestion

We report the case of a 16-year-old healthy adolescent male who presented to the local emergency department with altered mental status. En route to a tertiary care facility, he began to decompensate and was found to be markedly acidotic. Further investigation revealed an elevated anion gap, and physical examination showed only abdominal pain and decreased level of consciousness. A broad differential diagnosis was considered at the time of the patient's presentation at the tertiary care center including ingestion of a volatile alcohol, sepsis, and an abdominal catastrophe. Although fomepizole and emergent dialysis were being initiated, laboratory tests confirmed ethylene glycol poisoning. This case demonstrates the importance of early recognition of potential ingestions in patients with altered mental status and supportive laboratory findings.

Inherited or acquired metabolic disorders

This chapter starts with a description of imaging of inherited metabolic disorders, followed by a discussion on imaging of acquired toxic-metabolic disorders of the adult brain. Neuroimaging is crucial for the diagnosis and management of a number of inherited metabolic disorders. Among these, inherited white-matter disorders commonly affect both the nervous system and endocrine organs. Magnetic resonance imaging (MRI) has enabled new classifications of these disorders that have greatly enhanced both our diagnostic ability and our understanding of these complex disorders. Beyond the classic leukodystrophies, we are increasingly recognizing new hereditary leukoencephalopathies such as the hypomyelinating disorders. Conventional imaging can be unrevealing in some metabolic disorders, but proton magnetic resonance spectroscopy (MRS) may be able to directly visualize the metabolic abnormality in certain disorders. Hence, neuroimaging can enhance our understanding of pathogenesis, even in the absence of a pathologic specimen. This review aims to present pathognomonic brain MRI lesion patterns, the diagnostic capacity of proton MRS, and information from clinical and laboratory testing that can aid diagnosis. We demonstrate that applying an advanced neuroimaging approach enhances current diagnostics and management. Additional information on inherited and metabolic disorders of the brain can be found in Chapter 63 in the second volume of this series.