Neuropatia óptica tóxica por inalação de metanol / Optic neuropathy toxic after methanol inhalation

Resumo A intoxicação por metanol é um evento considerado raro, principalmente quando feita por via inalatória. Retratou-se neste presente estudo um relato de caso de um paciente que desenvolveu neurite óptica tóxica após exposição ao metanol e ácido acético por via inalatória em seu ambiente de trabalho. Foi descrito sobre as terapias obtidas na literatura, bem como as manifestações clínicas e o manejo a este paciente.

Abstract The methanol toxicity is considered rare event , especially when taken by inhalation . It was portrayed in the present study a case report of a patient who developed toxic optic neuritis after exposure to methanol and acetic acid by inhalation in the workplace . It was described for the therapies from the literature as well as the clinical manifestations and management in this patient.

Distribution of Formic Acid after Methanol Intoxication in Rats / 法医学杂志

OBJECTIVE@#To investigate concentration and distribution in blood and tissues of formic acid after methanol intoxication in rats.@*METHODS@#The Sprague-Dawley rats were divided into groups for control group and 3-day and 7-day intoxication treatment groups. The experimental groups were administered methanol by gavage with the initial dose of 8 mL/kg and followed with 4 mL/kg supplemental dose 24 h later. After 3 days and 7 days later, rats were killed by decapitation. Then samples of cardiac blood, liver, kidney, brain, heart and stomach of each group were collected. Formic acid concentrations were detected by high performance liquid chromatography.@*RESULTS@#Formic acid concentrations in tissues were higher than in blood. Compared with 3-day intoxication group, there was an increase formic acid of concentration in brain and stomach in 7-day intoxication group, while a decrease in liver and kidney (P < 0.05).@*CONCLUSION@#High performance liquid chromatography could be used to accurately detect formic acid. As the metabolite of methanol, formic acid accumulates in rat blood and tissues after intoxication and the concentrations in organs and tissues are obviously higher than in blood.

Changes of oscillatory potentials of electroretinogram after methanol intoxication in rats / 法医学杂志

OBJECTIVE@#To study the characters of oscillatory potentials (OPs) of electroretinogram (ERG) after methanol intoxication in rats.@*METHOD@#The SD rat models of methanol intoxication were established and divided into control group, 3-day intoxication group, 7-day intoxication group. The changes of OPs of ERG were recorded in a dark room.@*RESULTS@#The total amplitudes of 3-day and 7-day intoxication groups decreased approximately 50% compared with that of the control group, while the schedule delayed approximately 16% and 61%, respectively.@*CONCLUSION@#The characters of methanol intoxication in rats included delay in schedule and decline in the total amplitude of OPs.

Intoxicación por alcohol metílico: a propósito de un caso / Methyl alcohol intoxication: a propos of a case

Se presenta un caso típico de intoxicación fatal por metanol. El paciente, barnizador de profesión, acude al día siguiente de ingestión errónea de 30 mls de alcohol metílico puro, quejándose de vómitos, mareos, visión borrosa, toma del sensorio e hipernea, la gasometría arterial mostró acidosis metabólica con hiato osmolar aumentado. Ante la sospecha de presencia de alcohol metílico se comenzó tratamiento específico, con soluciones alcalinizantes, alcohol etílico y hemodiálisis, a pesar de lo cual el paciente fallece. La precocidad en la administración de las medidas terapéuticas es crucial a fin de limitar el daño y posibilitar la recuperación. Se presenta el caso por ser complejo y de presentación poco frecuente, que habitualmente requiere la presencia de un equipo multidisciplinario

It is presented a typical case of fatal methanol intoxication. The patient, varnisher by profession, goes the day after the mistaken ingestion of 30 mls of pure methyl alcohol, complaining of vomiting, dizziness, blurred vision, sensory taking and hyperpnea, arterial gasometry showed metabolic acidosis with increased osmolal gap. Suspecting the presence of methyl alcohol specific treatment is started with alkalizing solutions, ethyl alcohol and hemodialysis, yet the patient dies. Precocity in the administration of therapeutic measures is crucial to limit the damage and enable recovery. The case is presented because it is complex and unusual presentation, which usually requires the presence of a multidisciplinary team

Electroretinogram and histopathologic changes of the retina after methanol intoxication / 法医学杂志

In order to study the functional and structural alterations of the retina in SD rat model after methanol intoxication, 35 rats were divided randomly into five groups administrated with saline, 3-day high dose, 7-day high dose, 3-day low dose and 7-day low dose methanol separately. The retinal function of each group was assessed by flash electroretinogram (F-ERG) 3 and 7 days after methanol poisoning. The microstructure and ultrastructure of the retina were observed at the same time. The high-dose methanol intoxication induced irreversible retinal functional and structural damages 3 days after poisoning, which included prolonged latency and reduced amplitude of the Max-reaction of F-ERG. These injuries were aggravated 7 days after poisoning. Meanwhile, the latency and amplitude of the Cone-reaction of F-ERG were also affected 3 days after poisoning, but there were no further worsening tendency 7 days after poisoning. The retinal histological analysis showed cellular edema, heteromorphy and disarrangement, tissular loosen of the inner nuclear layer and photoreceptors layer. The mitochondrial damage began at the photoreceptors layer and developed further into the inner nuclear layer. The low-dose methanol intoxication only caused transient damage of the retina. Our results showed that the function and structure of the photoreceptor and inner nuclear layer were the primary target of methanol intoxication and that the rod cells were more sensitive to methanol intoxication than the cone cells. The mitochondrial damage developed from outer layer to inner layer of the retina.

An Outbreak of Food Borne Illness Due to Methomyl Pesticide Intoxication in Korea

On February 21, 2013, 6 elderly people collapsed abruptly after eating bean sprout bibimbab (boiled rice mixed with bean sprouts and seasoned with soybean sauce) at a countryside restaurant in the Chungbuk Province, Korea. Minutes after eating the meal, all of the patients lapsed into a state of stupor. Respiratory arrest developed in 2 patients; and one of two patients died of cardiac arrest. The autopsy identified methomyl and methanol in the deceased patient's gastric contents and in the remaining soybeanbean sauce seasoning. Five of the 6 patients ingested one spoonful of the soybeanbean sauce seasoning and survived, while one patient who died of cardiac arrest, ingested approximately two spoons. Symptoms of toxicity presented quickly in the subjects and progressed rapidly, including chest tightness, an unusual sensation in the pit of the stomach, dizziness, ataxia, and finally, collapse. Three patients who drank ethanol with the meal experienced only mild toxic symptoms. Our analysis of the clinical observations in these cases suggests that ingestion of methomyl pesticide and the additive toxicity of methanol may have been responsible for the intoxication.

Scenario of hooch tragedy in Gujarat state.

Currently, the Hooch Tragedy occurred in July 2009 at Ahmedabad, Gujarat, resulting in the death of 136 people from consumption of bootlegged liquor. This was the highest death toll in Gujarat from consuming moonshine since 1989 when 132 people had died in a matter of days in Vadodara. The number of patients admitted in the four hospitals of Ahmedabad-Civil Hospital, V.S. Hospital, LG Hospital and Shardaben Hospital had risen to 276 with nearly 100 needing observation either in ICUs or surgical wards. Embarrassed by the scale of the tragedy in a state where consumption and sale of liquor is officially banned, police swept through Gujarat in search of those, illegally selling home-made liquor. Gujarat is the country's only state where sale and consumption of liquor is banned in deference to Mahatma Gandhi, a Gujarati who was passionately opposed to liquor. This has led to a proliferation of illegal liquor dens, whose home-made brew is mostly consumed by those from low income families who can't afford high priced drinks available outside the state.

A Case of Optic Nerve Atrophy with Severe Disc Cupping after Methanol Poisoning

We report a rare case of optic nerve atrophy with severe disc cupping resulting from methanol poisoning. A 30-year-old man presented to the hospital complaining of decreased visual acuity in both eyes a day after drinking alcohol containing methanol. His initial visual acuity allowed for only visualizing hand motion and not corrected in either eye. Initial intraocular pressure was within normal limits in both eyes. Initial fundus examination showed optic disc swelling in both eyes. Four years later, he visited our hospital for an eye evaluation. Visual acuity in both eyes still only allowed for visualizing hand motion. No nystagmus was observed in either eye during the optokinetic nystagmus test, and no waves were found in a visual evoked potential test. No specific change was noted on brain magnetic resonance imaging. On fundus examination, there was disc pallor in both eyes and disc cupping with a high cup/disc (C/D) ratio above 0.9 in the left eye. C/D ratio of the right eye was 0.5. Methanol poisoning may induce glaucomatous disc cupping in the late stage as well as optic atrophy. One possible mechanism of disc cupping is ganglion cell loss due to acute demyelination of the retrobulbar optic nerve. This report is the first photographic evidence of methanol induced optic disc cupping in Korea.

Letter to the Editor: A Case of Optic Nerve Atrophy with Severe Disc Cupping after Methanol Poisoning

No abstract available.

Características clínicas y evolución de los pacientes con intoxicación por metanol atendidos en un hospital general / Clinical characteristics and outcome of patients with methanol poisoning treated in a general hospital

Objetivo: Describir las características clínicas y la evolución de los pacientes con intoxicación por metanol. Material y métodos: Estudio descriptivo, transversal, retrospectivo, tipo serie de casos en pacientes con diagnóstico de intoxicación por metanol, atendidos en el Hospital Nacional Cayetano Heredia entre el 2004 y 2008. Resultados: Se encontraron 8 pacientes (6 varones y 2 mujeres) atendidos por intoxicación por metanol, 6 sobrevivieron. En todos los casos la vía de ingreso fue oral, 7 en forma accidental; 4 de los pacientes tenía antecedentes de dependencia alcohólica y 3 de depresión. Al ingreso, 7 presentaron alteración del nivel de conciencia, 7 visión borrosa y 4 vómitos y los niveles de metanol sérico estuvieron entre 67 a 93 mg/dL. Todos los pacientes presentaron acidosis metabólica con anión gap elevado. Los pacientes fallecidos tuvieron pH menor de 7,0. La principal complicación fue neumonía aspirativa. Conclusiones: Debido al escaso número de casos no podemos llegar a conclusiones; sin embargo, podemos decir que la intoxicación por metanol generalmente se produce por ingesta accidental, debido al consumo de licores adulterados en varones adultos de limitados recursos económicos, los síntomas más frecuentes de presentación son la alteración de la conciencia y la visión borrosa, y aparentemente el riesgo de muerte está relacionado con la severidad de la acidosis metabólica.

Objective: To describe clinical characteristics and evolution of patients with methanol poisoning. Methods: A descriptive, transversal, retrospective study, case series report of patients with methanol poisoning at the Hospital Nacional Cayetano Heredia between 2004 and 2008. Results: We found 8 patients (6 men and 2 women) with methanol poisoning, 6 survived. In all cases pathway entrance was oral, 7 were accidental; 4 patients were alcoholics and 3 had depression. At admission, 7 had consciousness disorder, 7 blurred vision, 4 vomits and serum methanol levels were between 67-93 mg/dl. All patients had metabolic acidosis with elevated anion gap. The main complication was aspiration pneumonia. Conclusions: Due to the small number of cases we can reach conclusions, but we can say methanol poisoning is usually caused by accidental ingestion, mainly from adulterated liquor consumption by adult men with limited economic resources, most common symptoms are consciousness disorder and blurred vision, and apparently risk of death is related to severity of metabolic acidosis.

Advancement of methanol poisoning mechanism research / 法医学杂志

The methanol poisoning by oral intake or skin contact occurs occasionally, which may have serious consequences including blindness and/or death. Methanol and its metabolites, formaldehyde and formic acid, are associated with metabolic acidosis, visual dysfunction and neurological symptoms. At present, the mechanism of methanol poisoning primarily focuses on the cell hypoxia, the alteration of structure and biological activity induced by free radical and lactic acid. Meanwhile, methanol poisoning causes changes in the balance between the production of free radicals and antioxidant capacity and in the proteases-protease inhibitors system, which lead to a series of disturbances.

Suicide attempt using pure methanol with hospitalization of the patient soon after ingestion: case report / Tentativa de suicídio com metanol puro em paciente admitido precocemente após a ingestão: relato de caso

CONTEXT: Most patients with methanol poisoning typically show up one to several days after ingestion, presenting severe acidosis, visual disorders, or both. Reports of hospitalization less than 6 h after exposure are unusual. We describe a case of attempted suicide using methanol admitted 3 h after ingestion. CASE REPORT: A 52-year-old male was hospitalized 3 h after intentional ingestion of 150 ml of 99.9 percent methanol with no co-ingestion of ethanol. He was alert and cooperative, presenting nausea and vertigo, and reporting six episodes of vomiting. Physical examination showed no remarkable features. A blood sample for methanol and ethanol determination was obtained 4 h after ingestion. The result (available 10 h after ingestion) showed 70 mg/dl of methanol, without detectable ethanol. He was treated with a loading dose of 10 percent ethanol solution (7 ml/kg, intravenously), followed by a maintenance dose of 0.9-1.0 ml/kg/h intravenously (10 to 51 h); hemodialysis (19 to 27 h, together with 2.1 ml/kg/h of 10 percent ethanol intravenously); and folinic acid intravenously (50 mg every 6 h, from 4 to 51 h). He developed mild/moderate metabolic acidosis without acidemia and was discharged on day four after ophthalmological evaluation and cerebral computed tomography scan, without abnormalities. Follow-up revealed no sequelae. CONCLUSION: This could be classified as a potentially severe case of methanol poisoning, according to the amount and concentration of methanol ingested, and blood methanol concentration at 4 h. The good outcome was attributable to early hospitalization and early antidotal therapy with hemodialysis, starting at 10 and 19 h, respectively.

CONTEXTO: A maioria dos pacientes intoxicados por metanol se apresenta um a vários dias após a ingestão, com acidose grave e/ou alterações visuais, sendo rara a admissão com menos de seis horas da exposição. Descrevemos uma tentativa de suicídio com metanol puro admitido três horas após a ingestão. RELATO DE CASO: Homem de 52 anos, admitido três horas após ingestão intencional de 150 ml de metanol 99,9 por cento sem co-ingestão de etanol. Ele estava alerta e cooperativo, apresentando náuseas, vertigem e relatando seis episódios de vômitos. Sem achados relevantes no exame físico. Foi coletada amostra sanguínea para determinação dos níveis séricos de metanol e etanol em quatro horas, com resultado liberado em 10 horas, mostrando metanol = 70 mg/dl e etanol não detectável. O paciente foi tratado com uma dose de ataque intravenosa (IV) de etanol 10 por cento de 7 ml/kg, seguida por uma dose de manutenção de 0,9-1,0 ml/kg/h IV de 10 a 51 horas; hemodiálise (19 a 27 horas), recebendo, nesse período, 2,1 ml/kg/h de etanol 10 por cento IV e oito doses de ácido folínico IV (50 mg cada 6 horas, de 4 a 51 horas). Desenvolveu acidose metabólica leve/moderada, sem acidemia, sendo liberado no quarto dia de internação após avaliação oftalmológica e realização de tomografia computadorizada cerebral, sem alterações. Acompanhamento não revelou sequelas. CONCLUSÃO: O presente caso pode ser classificado como uma intoxicação potencialmente grave por metanol, considerando a quantidade e a concentração ingerida e o nível sérico de metanol obtido em quatro horas. A boa evolução pode ser atribuída ao intervalo entre a exposição e a admissão hospitalar, e o tratamento específico com o antídoto e a hemodiálise, respectivamente iniciados em 10 e 19 horas.

Extracorporeal methods in the treatment of poisoning.

Among the various ways of managing poisoning, haemodialysis may help in enhancing excretion of the toxic substance. We report a case, a Russian male, 35 years old, who was rushed to the Gleneagles Hospital Medan from the airport after being evacuated from Banda Aceh together with another older Russian who died as they arrived at the admission and Emergency Department. From the result of intensive allo anamnesis and the high anion gap metabolic acidosis, in the absence of disturbed renal and liver function, we presumed this patient was suffering from methanol intoxication. The time of exposure was approximately 70 hours before. The exact length of dialysis time to excrete the noxious substance from the blood without plasma methanol determination was difficult. Moreover the time elapsed from exposure to treatment had been approximately 70 hours, which means the optic nerve had been so long exposed to formic acid, the toxic metabolite of methanol, that the damage should have been very severe. Ethanol is also known to be an antidote of methanol, which can be given orally by nasogastric tube, or i.v. It should be given early, and plasma ethanol level should be closely monitored to make it effective and safe. This was also unavailable. Another antidote is fomepizole which is also as yet unavailable in Medan. Folic acid, thiamin, and i.v. folinic acid are also recommended by the literature, as well as oral steroid.

Methanol poisoning in medical intensive care unit.

A series of eight cases of methyl alcohol poisoning resulting from consumption of adulterated alcohol is presented. Most of the patients had blurring of vision followed by coma, metabolic acidosis and hemodynamic unstability (SBP < 90 mmHg) on admission to medical ICU. Early recognition and prompt initiation of treatment lead to successful recovery in five of these patients. Analysis of correlation between clinical and biochemical indicators of severity and indication for various therapeutic interventions are discussed.