Metaldehyde Poisoning Research Articles

Gas chromatography-tandem mass spectrometric analysis of metaldehyde and its metabolite acetaldehyde in initial assessment of hemodialysis abatement of toxicity in live animals

Metaldehyde consumption by pets and other mammals constitute medical emergencies ideally requiring rapid poison removal. The purpose of this study was three-fold: 1) development of a sensitive method for metaldehyde quantitation in patient serum samples by gas chromatography combined with tandem quadrupole mass spectrometry (GC/MS/MS); 2) development of a sensitive method for quantitation of the volatile metaldehyde metabolite acetaldehyde by headspace analysis combined with GC/MS/MS; and 3) an initial assessment of the efficacy of combined dialysis and hemoperfusion treatments in diminishing toxin loads in canine victims of metaldehyde poisoning. Both mass spectrometric approaches relied on Multiple Reaction Monitoring (MRM) methodologies. Metaldehyde extracted via liquid-liquid partitioning from serum was detected with a limit of quantitation (LOQ) of 7.3 ± 1.4 ng/mL with linearity in the range 1–250 ng/mL with accuracy improved by inclusion of a deuterated metaldehyde internal standard. Acetaldehyde was determined to have an LOQ of 0.39 μg/mL with linearity in the range 1–1000 μg/mL. The developed methodologies were applied to canine samples taken over various time points during dialysis treatment. Two of three canine patients showed significant abatement of metaldehyde levels by over 50-fold from initial concentrations while a third was shown to be negative with no measureable metaldehyde. The toxic metabolite acetaldehyde was found in one of the metaldehyde-poisoned patients and the detected acetaldehyde was also reduced by roughly 200-fold during the course of treatment. The designed mass spectrometric techniques were thus successful in demonstrating the efficacy of the applied dialysis-hemoperfusion methods which may find wider applicability against other potentially lethal toxins in poisoned patients in future studies.

Analysis of Metaldehyde in Animal Whole Blood and Serum by Gas Chromatography-Mass Spectrometry.

Metaldehyde, a widely used molluscicide, is the third cause of intoxication by pesticides in domestic animals in Europe. Most mammalian species are susceptible, and its exposure may lead to death within a few hours. While metaldehyde intoxication diagnosis is in most cases presumptive, based on the symptomatology or from "postmortem" analysis, few analytical methods are currently available for live animals. The aim of this work was to describe a fast analytical method for the specific and quantitative determination of metaldehyde in animal whole blood and serum at concentrations of toxicological significance. A liquid-liquid extraction with chloroform and gas chromatography-mass spectrometry quantification are proposed. The method limit of quantification (LOQ) was 0.04 µg/mL in serum and whole blood. The method was linear in the range from 0.04 to 200 µg/mL. The recovery was between 93% and 102% for LOQ, low, medium and high spike concentrations. Intra- and inter-assay relative standard deviation was <12% in all spike concentrations in both serum and whole blood, apart from one of the experiments at LOQ in whole blood, which accounted for 17.7%. The method was applied to real intoxication cases, and the concentration found in positive samples was between 29 and 69 µg/mL. The proposed method provides high sensitivity, accuracy and precision and can be used to assist in the diagnosis of metaldehyde poisoning.

A prospective study on clinical signs, management, outcomes, and delayed neurologic sequelae due to metaldehyde poisoning in 26 dogs.

Metaldehyde poisoning in dogs is well known and described issue. Several studies focused on the incidence, epidemiological features, and clinical and pathological findings associated with this intoxication. However, there are no prospective studies of metaldehyde poisoning and late-onset seizures. To prospectively describe clinical signs, therapeutic management, outcomes, and delayed-onset seizures due to metaldehyde poisoning in dogs. A 15-month prospective study on dogs with a diagnosis of metaldehyde poisoning, either via phone call to the animal poison control center or analysis at the toxicology laboratory in Lyon, France. Clinical signs, therapeutic management and outcomes, and the late onset of seizures were assessed for at least 3 years. Twenty-six dogs were enrolled in the study. The most prevalent clinical signs were ataxia (18 dogs), convulsions (17), hypersalivation (15), and tremors (15). Treatment was symptomatic (e.g., activated charcoal, emetic therapy, and intravenous fluids) with anticonvulsant therapy (mainly diazepam). The overall survival rate was 81% (21/26 dogs). All dogs that received active charcoal (11/11) or emetic therapy (4/4) survived. Twelve of 17 dogs had convulsions and survived; 9 were followed up for at least 3 years after poisoning, and none had any other seizure episode or neurological sequelae. This prospective study describes clinical signs, therapeutic management and outcome of metaldehyde poisoning in dogs, and late-onset neurologic sequelae. None of the nine cases that were followed for 3 years developed neurological signs after metaldehyde poisoning. Therefore, long-term antiepileptic therapy is not indicated.

Molluscicide toxicosis in dogs

Slug and snails are important garden pests and intermediate hosts of lungworm, and various products are available for their control. Metaldehyde has long been used in molluscicide products and poisoning in dogs is common, having rapid-onset and prolonged seizure activity. However, these products are to be banned for outdoor use in the UK in spring 2022. This should eventually reduce the incidence of metaldehyde poisoning in pets. Methiocarb, a carbamate pesticide, was also used in slug baits but was banned in 2015. Cases still occasionally occur, characterised by rapid-onset gastrointestinal, respiratory and neurological signs. Ferric phosphate is now commonly found in slug and snail control products. Ingestion generally causes gastrointestinal signs only, because the iron in ferric phosphate has low oral bioavailability. Pets may also be exposed to slug deterrent products, which often contain diatomaceous earth or wool pellets. These generally have low toxicity for dogs. However, diatomaceous earth can cause skin irritation or severe respiratory signs if inhaled, and wool pellets may cause gastrointestinal signs. Management of dogs with mollusicide toxicosis is supportive, based on clinical signs.

Forenzička patologija u prosuđivanju zlostavljanja životinja - trovanje životinja metaldehidom

Metaldehyde is the active ingredient in molluscicide that is used against snails. Poisoning of animals can be accidental or intentional. Metaldehyde poisoning is most often recorded in dogs. Clinical signs can develop within 10 minutes, mostly 1-3 hours after metaldehyde ingestion. There is no antidote for metaldehyde and therapy comes down to elimination of poison from organism and control of muscle tremor and convulsions. This paper presents our experiences in the forensic investigation of animal abuse by poisoning with metaldehyde (three dogs, one cat, and one hedgehog). Pathoanatomical and histopathological findings are shown. Reasonable suspicion of poisoning with metaldehyde is based on the finding of specific cyan-coloured gastrointestinal contents. The final diagnosis is made by toxicological evidence of metaldehyde in liver, kidney and gastric content of the poisoned animal.

Brachial Plexopathy from Metaldehyde Poisoning – A Case Report

We describe the case of a middle-aged female with schizophrenia, who developed acute sensorimotor deficits of the right upper limb within a week of ingesting large amounts of metaldehyde in a suicide attempt. A right-sided brachial plexopathy was diagnosed clinically and supported by electrophysiologic assessments and targeted magnetic resonance imaging scans. Although metaldehyde’s neurotoxicity typically affects the central nervous system, focal involvement of the peripheral nervous system remains unreported in medical literature, and its pathogenic processes await further elucidation. Therefore, we recommend the continued observation for the subsequent development of sensorimotor deficits during the first week of metaldehyde poisoning.

In dogs with metaldehyde intoxication, are benzodiazepines more effective than methocarbamol in relaxing muscles and reducing tremors?

PICO question&#x0D; In dogs with metaldehyde intoxication, are benzodiazepines (e.g. diazepam, midazolam) more effective than methocarbamol in relaxing muscles and reducing tremors?&#x0D; &#x0D; Clinical bottom line&#x0D; Category of research question&#x0D; Treatment&#x0D; The number and type of study designs reviewed&#x0D; Five papers were critically reviewed. There were five retrospective case series&#x0D; Strength of evidence&#x0D; Weak&#x0D; Outcomes reported&#x0D; Currently, five retrospective case series exist in the literature which discuss metaldehyde intoxication cases treated mainly with benzodiazepines, a few of which had methocarbamol. There is not really any study to compare directly benzodiazepines with methocarbamol. In addition to that, factors such as commercial (e.g. the low availability of methocarbamol in the UK market compared to the US market), administrational (e.g. multiple administration routes of benzodiazepines) and pharmacological (e.g. lack of anticonvulsant function of methocarbamol), have played an important role in the treatment choice. Several case reports exist as well&#x0D; Conclusion&#x0D; Currently, there is insufficient evidence to determine whether benzodiazepines are more effective than methocarbamol in relaxing muscles and reducing occurrence of muscle tremors&#x0D; &#x0D; How to apply this evidence in practice&#x0D; The application of evidence into practice should take into account multiple factors, not limited to: individual clinical expertise, patient’s circumstances and owners’ values, country, location or clinic where you work, the individual case in front of you, the availability of therapies and resources.&#x0D; Knowledge Summaries are a resource to help reinforce or inform decision-making. They do not override the responsibility or judgement of the practitioner to do what is best for the animal in their care.&#x0D; &#x0D;

Fatal metaldehyde poisoning in a dog confirmed by gas chromatography

BackgroundMetaldehyde is a toxic pesticide used mainly as a molluscicide, responsible for intoxication and deaths in both humans and animals. Accidental exposure to metaldehyde in dogs is considered rare, but severe. Data concerning clinical and veterinary forensic toxicology are largely incomplete, especially regarding case reports in dogs. The present work reports a complete and detailed description of a case from the history, clinical evolution, pathological exams and toxicological diagnosis in an accidental case of metaldehyde poisoning in dog.Case presentationAn eleven-month-old, 3.0 kg, male German Spitz was presented for emergency care with acute vomiting and seizures 3 hours after suspected accidental ingestion of commercial molluscicide containing 3% metaldehyde (Lesmax®). The animal was in lateral recumbency and showed stuporous mentation, salivation, tonic-clonic status epilepticus, systemic tremors, bilateral miosis, absent palpebral, corneal, oculovestibular and gag reflexes, severely depressed spinal reflexes, dyspnea and tachycardia. Despite treatment, the patient progressed to comatose mentation and died. Necropsy examination revealed discrete lesions in the liver and central nervous system, while stomach examination revealed content of feed, activated charcoal and blue-green granules, compatible to the commercial formula of metaldehyde. Histology examination revealed extensive hemorrhage and severe centrolobular necrosis of the liver and tumefaction of Kupfer cells. Brain samples showed discrete hemorrhage and hyperemia. In order to confirm the diagnosis, samples from feces, stomach content, spleen, liver, heart, kidneys and brain were submitted gas chromatography analysis. Results confirmed the presence of metaldehyde in all samples. We describe clinicopathological abnormalities of a fatal case of metaldehyde poisoning in a dog, as well as postmortem diagnosis using gas chromatography.ConclusionMetaldehyde poisoning is rarely reported, since the diagnosis is often difficult and the notifications scarce. To our knowledge, this is the first report describing clinical signs, pathological findings and chromatographic diagnosis. This report aims to contribute to the understanding of the pathogenesis of metaldehyde intoxication, to further explore veterinary forensic toxicology diagnosis.

Retrospective evaluation of the use of hemodialysis in dogs with suspected metaldehyde poisoning (2012-2017): 11 cases.

To evaluate dogs treated with hemodialysis for severe metaldehyde intoxication and to compare them with conventionally-managed patients. Retrospective study (2012-2017). University teaching hospital. Data from 18 dogs with severe metaldehyde intoxication were analyzed. Eleven dogs were treated with intermittent hemodialysis and 7 managed conventionally. None. Metaldehyde poisoning was diagnosed based on clinical signs and toxicological analysis or presence of turquoise material in the gastrointestinal content. Clinical signs, additional treatments, dialysis prescription, duration of anesthesia and hospitalization, complications, and outcome were documented. Results were analyzed by t-test, Mann-Whitney U-test, and Chi-square test. P<0.05 was considered significant. Dialysis was performed for median (range) 180min (150-420min) with median of 2.28 L/kg (1.66-4.48 L/kg) blood volume processed. In the hemodialysis group, anesthesia was discontinued at a median of 3.0 hours (1.5-6.7 h) after starting dialysis. The conventional-group received general anesthesia for a median of 17.5 hours (7.0-30.5 h). No further anticonvulsive treatment was necessary for the hemodialysis group. Time to hospital discharge was shorter in dialyzed dogs (median 18 h; 15-41 h) compared to conventionally treated dogs (median 89 h; 61-168 h; P=0.0014). Aspiration pneumonia was reported in 5 conventionally treated dogs and none of the dialyzed dogs (P=0.001). Five dialyzed dogs developed hematoma at the dialysis catheter site. One dog in each group was euthanized. Hemodialysis significantly decreases the requirement for anesthesia and length of hospitalization in dogs with metaldehyde intoxication. Aspiration pneumonia occurred less often in dialyzed patients. Prospective studies are warranted to confirm the clinical utility of hemodialysis in dogs with metaldehyde poisoning.

Super-refractory nonconvulsive status epilepticus due to self-poisoning with metaldehyde

IntroductionMetaldehyde self-poisoning in adults is uncommon and, to the best of our knowledge, an episode of super-refractory nonconvulsive status epilepticus (sr-NCSE) following an suicide attempt has not been previously demonstrated. Case reportA 68-year-old woman was admitted to our Intensive Care Unit (ICU) in coma. On neurologic examination, the pupils were reactive, brainstem reflexes were present and plantar responses were flexor bilaterally. Routine laboratory tests were unremarkable. Arterial blood gas analysis revealed a mixed acidosis. A computed tomography (CT) scan of the brain and angio-CT were normal. The family confirmed that the patient had had suicidal ideation, and they had discovered a bag of slug killer (metaldehyde 5%) in her room. Two hours after the admission at the ICU, her neurological state remained unchanged. Sedation with intravenous propofol and antiepileptic therapy with levetiracetam (1000 mg/24 h) were started. The next day, propofol infusion was stopped but the level of consciousness of the patient did not improve. A video-electroencephalograhy (v-EEG) showed continuous generalized paroxysms of spike-wave and sharp-slow wave complexes compatible with the diagnosis of generalized NCSE. On day 3, the episode of NCSE was controlled. Finally, 15 days after ICU admission she was discharged with a normal neurological examination. ConclusionThis clinical case highlights that in comatose patients as consequence of metaldehyde poisoning, a v-EEG evaluation should be perform in order to rule out the existence of NCSE.

Metaldehyde Poisoning of Companion Animals: A Three-year Retrospective Study.

IntroductionIntentional and accidental poisoning of animals is often caused by readily available commercial pesticides, such as the molluscicide metaldehyde. A retrospective analysis of suspected metaldehyde poisonings between 2014 and 2016 in Italy was conducted.Material and MethodsBiological matrices were collected for toxicological analyses in the course of routine Institute activity. A total of 183 organs from dogs and cats and 49 pieces of bait, here specifically poisoned food used to lure animals, were analysed and the presence of metaldehyde was confirmed by gas chromatography coupled to mass spectrometry (GC/MS).ResultsA high content of metaldehyde was demonstrated in the analysed samples from dogs and cats: 50 (27.3%) animals were found positive for metaldehyde intoxication together with 17 pieces of bait.ConclusionThe study emphasised the need for the control of metaldehyde use by the veterinary service.

Successful treatment of metaldehyde toxicosis with intravenous lipid emulsion in a dog

The aim of the present report is to describe a novel successful treatment approach for metaldehyde poisoning in a dog: intravenous lipid emulsion therapy (ILE). A 2.5-month-old female Labrador Retriever was referred to the Emergency Department following deliberate ingestion of a metaldehyde-containing granular bait. Severe continuous tonic-clonic activity, muscle tremors, loss of consciousness, diffuse congestion of the oral mucosa, tachycardia, tachypnoea and nystagmus were observed upon admission. Additional intravenous administration of a 20% lipid emulsion resulted in normalization of the vital signs and complete neurological recovery. To the authors’ knowledge, this is the first report describing ILE in the treatment of canine metaldehyde intoxication and the first description of a case of metaldehyde poisoning in a dog in Romania. Considering the severity of the neurological signs and the fact that no specific antidote is known, treatment can be significantly challenging to the veterinary practitioner. This finding should be included in metaldehyde poisoning therapy protocols, especially when severe clinical signs fail to respond to symptomatic treatment.

Metaldehyde poisoning in dogs

Metaldehyde is an active substance used for extermination of slugs and snail population. This paper presents the very first case of metaldehyde intentional poisoning of dogs in Serbia. Three-year-old and a six-year-old Swiss white shepard dogs were poisoned. The owner noticed frequent defecation, skeletal muscles spasms and impossibility to put any weight on their back extremities. The vomit of the younger dog was made of green-turquoise colored gut content. Twenty minutes after the onset of the first clinical symptoms dogs died. Macroscopic examination showed congestion of lungs, in the liver and intestines, as well as chemorage in the pancreas, bladder and intestines. Nonspecific pathological lesions were present in the lungs, heart, kidneys, liver, gut, intestines and brain. Pathohistological examination showed dystrophic changes and necrosis in kidneys, brain and intestines. According to anamnestic data, clinical signs, macroscopic and microscopic examination as well as characteristic smell of gut content, one could say that metaldehyde poisoning is the case. Toxicological analysis of gut content samples was performed by using gas chromatography with mass spectrophotometry (GC-MS). Used diagnostic methodology and gut content toxicology results obtained was the base for crime case according to article 269. Republic of Serbia Crime law.

Metaldehyde intoxication in a red fox (Vulpes vulpes)

Metaldehyde toxicity has been commonly reported in different species, including dogs, cats, horses, livestock and wildlife, but the authors are not aware of previously described cases in red foxes. A...

Determination of metaldehyde in human serum by headspace solid-phase microextraction and gas chromatography–mass spectrometry

A rapid headspace solid-phase microextraction–gas chromatography–mass spectrometry (HS–SPME–GC–MS) method has been developed for the determination of metaldehyde in human serum samples. Metaldehyde is extensively used as a molluscicide for the control of slugs and snails, and cases of metaldehyde poisoning have been reported. Metaldehyde was headspace-extracted on a polydimethylsiloxane (PDMS) fiber at 70 °C for 25 min, desorbed, and analyzed rapidly by GC–MS. The method was validated for limit of detection (LOD), linearity, precision, and recovery. Although the recovery of the sample was very low, the method itself was rapid with a low detection limit of 0.25 μg/ml, R.S.D. value 12.6%, and linearity range 0.5–25.0 μg/ml ( r 2 = 0.999). The results demonstrated that the SPME–GC–MS method for the analysis of metaldehyde is simple, rapid, solvent-free, and does not require any pre-analysis conversions.

Metaldehyde poisoning of dogs

SIR, — We were interested to read Nicholas J. Mills' letter ( VR , September 6, 2008, vol 163, p 310) concerning metaldehyde poisoning of dogs. Metaldehyde intoxications of companion animals generate many inquiries to the Veterinary Poisons Information Service (vpis) per annum. A significant

Self-poisoning with metaldehyde

Metaldehyde poisoning is rare. This case report details the largest toxic dose of self-poisoning with metaldehyde ever recorded in the literature to the authors’ knowledge, the aim being to emphasise...

Clinical, neurological and clinicopathological signs, treatment and outcome of metaldehyde intoxication in 18 dogs

To describe the clinical signs, clinicopathological abnormalities and outcome of metaldehyde intoxication in dogs. Medical records of dogs presenting between 1989 and 2005 with a diagnosis of metaldehyde toxicity were reviewed retrospectively. Data obtained from the medical record included signalment, history, clinical signs, laboratory tests results, hospitalisation period length, treatments and outcome. Eighteen dogs fulfilled the inclusion criteria. The most prevalent clinical signs were seizures, hyperthermia, tachycardia and muscle tremors. Serum biochemistry abnormalities included increased serum muscle enzymes activities, acidaemia (six dogs) and decreased blood bicarbonate (eight dogs). Treatment was symptomatic and supportive. Hyperbilirubinaemia was observed in two dogs. Diazepam was the most commonly used anticonvulsant followed by phenobarbitone and pentobarbital. General inhalant anaesthesia was required in nine of 18 dogs with seizures unresponsive to anticonvulsants. The survival was 83 per cent (15 of 18 dogs). This clinical study recorded, for the first time in the veterinary literature, several clinicopathological abnormalities from severely intoxicated dogs. Metabolic acidosis was common, while acute or delayed hepatotoxicity was an uncommon complication.

Zoonoses and other findings in hedgehogs (Erinaceus europaeus): a survey of mortality and review of the literature

A survey of mortality in hedgehogs (Erinaceus europaeus) was carried out between July 1976 and November 1986. Most were from Norfolk. Of the 74 examined, 35 (47.3 per cent) were road casualties, one of which yielded Salmonella typhimurium phage type (PT) 104. Of the remaining 39, 13 (33.3 per cent) had salmonellosis due to S enteritidis PT 11. This organism, which appears to be common and widespread in hedgehogs in England was found in 10 separate incidents. The only other zoonosis was ringworm (Trichophyton erinacei infection). Other findings included ectoparasitic infestations with mange mites (Caparinia tripilis), fleas (Archaeopsylla erinacei) and ticks (Ixodes hexagonus). Helminths comprised Crenosoma striatum lungworms (associated with Bordetella bronchiseptica infection in one animal), intestinal nematodes (Capillaria species), cestodes (Rodentolepis erinacei), trematodes (Brachylaemus erinacei) and acanthocephalans (Prosthoryhnchus species). Metaldehyde poisoning was diagnosed in three animals. Over a 10 year period 370 carcases were counted on a stretch of 18 miles of road in Norfolk. The major causes of mortality are probably road casualties and hypothermia during the winter months. In December 1988 S enteritidis PT 11 was isolated from three of four carcases examined in Berkshire and the zoonosis pseudotuberculosis (Yersinia pseudotuberculosis infection) was diagnosed in two of them.

Metaldehyde poisoning in a dairy herd.

Metaldehyde poisoning in a dairy herd.