Neurotoxidad inducida por ifosfamida / Ifosfamide-induced neurotoxicity

Introducción: La ifosfamida es un agente alquilante utilizado para el tratamiento de enfermedades oncohematológicas. Entre sus eventos adversos agudos se encuentra la neurotoxicidad. Esta puede presentarse desde el inicio de la infusión hasta tres días después. El tratamiento consiste en suspender la administración y asegurar una adecuada hidratación. Objetivo: Describir eventos neurológicos asociados al uso de ifosfamida en pacientes pediátricos con enfermedades oncohematológicas. Materiales y métodos: Estudio observacional, descriptivo, retrospectivo y transversal. Los datos se obtuvieron de historias clínicas de pacientes internados en el Hospital Garrahan que infundieron ifosfamida y desarrollaron síntomas neurológicos. Se analizaron edad, diagnóstico de base, dosis de ifosfamida, síntomas neurológicos y su relación con la infusión, tratamiento instaurado, exámenes complementarios y posibles factores de riesgo asociados. Resultados: Se registraron un total de catorce eventos neurológicos en doce pacientes, sin diferencia de sexo, con una mediana de edad de 9,5 años. La enfermedad de base más prevalente fue osteosarcoma. Las convulsiones fueron el síntoma más frecuente (50%), seguido de somnolencia y paresias. La combinación de ifosfamida y etopósido con/sin carboplatino se asoció en un 36% cada uno. El 64% desarrolló neurotoxicidad dentro de las primeras cuatro horas. Ningún paciente presentó alteraciones en los exámenes complementarios. Todos presentaron recuperación ad integrum. Conclusión: Este estudio brinda información acerca del tiempo de aparición de esta complicación, lo cual facilitará su detección precoz y tratamiento oportuno (AU)

Introduction: Ifosfamide is an alkylating agent used for the treatment of cancer. Among its acute adverse events is neurotoxicity. This can occur from the beginning of the infusion up to three days afterwards. Treatment consists of discontinuing administration and ensuring adequate hydration. Objective: To describe neurological events associated with the use of ifosfamide in children with cancer. Materials and methods: Observational, descriptive, retrospective, and cross-sectional study. Data were obtained from clinical records of patients admitted to the Garrahan Hospital who received ifosfamide infusion and developed neurological symptoms. Age, baseline diagnosis, ifosfamide dose, neurological symptoms and their relationship with the infusion, treatment, complementary tests, and possible associated risk factors were analyzed. Results: A total of fourteen neurological events were recorded in twelve patients, without difference in sex and with a median age of 9.5 years. The most prevalent underlying disease was osteosarcoma. Seizures were the most frequent symptom (50%), followed by drowsiness and paresis. The combination of ifosfamide and etoposide with/without carboplatin was associated in 36% each. Sixty-four percent developed neurotoxicity within the first four hours. None of the patients presented with abnormalities in the complementary examinations. All recovered ad integrum. Conclusion: This study provides information about the time of onset of this complication, which will facilitate its early detection and timely treatment (AU)

Biomarkers of susceptibility and effect in car painters exposed to organic solvents / Biomarcadores de susceptibilidad y efecto en pintores de carros expuestos a solventes orgánicos

Abstract Introduction: Car painters are routinely exposed to organic solvents classified as carcinogenic and mutagenic substances. Objective: To characterize the population susceptibility and evaluate the genotoxic effects of exposure to organic solvents. Methods: A cross-sectional study comparing a group of car painters exposed to organic solvents with a non-exposed group. CYP2E1 polymorphisms and the presence of micronuclei in lymphocytes were determined. Results: One hundred twenty-two workers participated in the study: 62 who worked in car paint shops and were exposed to solvents, and 60 who were not exposed. There were statistically significant differences between the two groups regarding micronucleated cells and nucleoplasmic bridges frequencies (p=0.042 and p=0.046, respectively; exact likelihood ratio). Significant differences were found at the interaction between the CYP2E1 genotype c1c1 and occupational exposure to solvents, with higher frequencies of micronuclei (p= 0.013) and micronucleated cells (p= 0.015). However, when the frequencies of micronuclei, micronucleated cells and nucleoplasmic bridges in the exposure group were compared between the c1c1 and c2c2/c1c2 allele groups of the CYP2E1 polymorphism, statistically significant differences were found. Conclusions: This study confirms that when workers with CYP2E1 polymorphisms, specifically the c1c1 genotype, are exposed to organic solvents, they are more likely to have somatic cell mutations, a condition associated with increased susceptibility to diseases such as cancer

Resumen Introducción: Los pintores de vehículos automotores están rutinariamente expuestos a agentes como los solventes orgánicos, capaces de producir efectos mutágenos y carcinógenos. Objetivo: Caracterizar la susceptibilidad poblacional y evaluar los efectos genotóxicos debidos a la exposición a solventes orgánicos. Métodos: Estudio de corte transversal que comparó a un grupo de pintores de carros expuestos a solven tes orgánicos con un grupo de personas no expuestas. Fueron determinados tanto los polimorfismos de CYP2E1 como la presencia de micronúcleos en linfocitos. Resultados: Participaron 122 personas, 62 trabajadores de talleres de pintura de autos expuestos a solventes y 60 personas no expuestas. Con relación al cuestionario Q 16, 32% de los expuestos refirieron síntomas sugestivos de neurotoxicidad. Las frecuencias de células micronucleadas y de puentes nucleoplásmicos fueron significativamente mayores en los expuestos que en los no expuestos: p= 0.042 y p= 0.046, respectivamente, Razón de verosimilitud exacta). Fueron halladas diferencias significativas en la interacción de CYP2E1 (c1c1) y la exposición ocupacional a solventes, con mayores frecuencias de micronúcleos (p= 0.013) y de células micronucleadas (p= 0.015). Conclusiones: Este estudio reafirma que los trabajadores expuestos a solventes orgánicos con polimorfismos de CYP2E1, específicamente con genotipo c1c1, tienen mayor probabilidad de presentar mutaciones en las células somáticas, condición asociada con una mayor susceptibilidad a enfermedades como el cáncer

Approaches for a field diagnosis of abamectin poisoning in calves / Abordagem para um diagnóstico a campo da intoxicação por abamectina em bezerros

An approach for the diagnosis of an abamectin outbreak in calves in the field is described and discussed. In a Midwestern Brazilian property, nine out of a 52 newborn calves were affected and died, making up for morbidity, mortality, and lethality ratios of 17.3%, 17.3%, and 100%, respectively. Major clinical signs included tremors in various muscle groups, inability to stand, and difficult, wheezing breathing. Each affected calf had been treated subcutaneously with abamectin (0.4mg/kg/body weight). No lesions were found at necropsy or at histological examination. Major diseases of newborn calves were included in the differential diagnosis.(AU)

Uma abordagem para o diagnóstico de um surto de abamectina em bezerros a campo é descrita e discutida. Numa propriedade do Centro-Oeste brasileiro, nove de um lote de 52 bezerros de 3 dias de idade foram afetados e morreram, perfazendo quocientes de morbidade, mortalidade e letalidade, respectivamente, de 17,3%, 17,3% e 100%. Os principais sinais clínicos incluíam tremores em vários grupos musculares, incapacidade em se manter em pé, e respiração difícil e estertorosa. Cada bezerro afetado havia sido tratado por via subcutânea com abamectina, na dose de 0,4mg/kg/peso corporal. Não foram encontradas lesões na necropsia, nem no exame histológico. As principais doenças de bezerros recém-nascidos foram incluídas no diagnóstico diferencial.(AU)

Colistin induced neurotoxity: a case report and review of literature / Neurotoxicidade induzida pela colistina: relato de caso e revisão de literatura

OBJECTIVE: To describe a case of neurotoxity associated to Colistin. CASE DESCRIPTION: A 29-year-old black male under treatment for urinary tract infection with identification of Klebsiella pneumoniae in urine culture resistant to all carbapenem antibiotics, presented visual turbidity, paresthesia on the face and upper left limb, slowed and discordant speech in the fourth day of Colistin use. Symptoms improved after reduction of the dose of colistin with adjustment for renal function, with complete reversion after discontinuation of the drug. CONCLUSIONS: Colistin-mediated neurotoxicity must be suspected in patients with altered mental status of unknown etiology and therapy promptly interrupted.

OBJETIVO: Descrever um caso de neurotoxidade associada à Colistina. DESCRIÇÃO DO CASO (desnecessário repetição): Um homem negro de 29 anos sob tratamento para infecção do trato urinário com identificação de Klebsiella pneumoniae (escrever corretamente) em cultura de urina resistente a carbapenêmicos, apresentou turvação visual, parestesia em face e membro superior esquerdo, discurso lento e discordante na quarto dia de uso da Colistina. Os sintomas melhoraram após a redução da dose de colistina com ajuste para a função renal, com reversão completa após a descontinuação do fármaco. CONCLUSÕES: A neurotoxicidade mediada por colistina deve ser suspeitada em pacientes com estado mental alterado de etiologia desconhecida e a terapia prontamente interrompida.

Fatal neurotoxic envenomation following the bite of a greater black krait (Bungarus niger) in Nepal: a case report

Background Neurotoxic envenomation following bites by kraits (Bungarus species) is a leading cause of snakebite mortality in South Asia. Over a long time, this had been attributed only to one species, the common krait (Bungarus caeruleus). However, recent research has provided increasing evidence of the involvement of several krait species. Here, we report a fatal case of neurotoxic envenomation following the bite of a greater black krait (Bungarus niger) in Nepal. Case presentation A 33-year-old man was bitten in the outdoor corridor of his home in the eastern hills of Ilam district while handling a snake he thought to be non-venomous. He subsequently developed severe abdominal pain, frequent vomiting, and signs of neurotoxic envenomation leading to respiratory paralysis. The patient did not respond to Indian polyvalent antivenom given 4 h after the bite and died under treatment 8 h after the bite. This is the second time that a B. niger was observed in Nepal, the first documented case of envenomation by this species in the country and the sixth reported case worldwide. Conclusions Previous distribution records - from eastern India and western Nepal, from western hills in Nepal, and from lowland localities in India and Bangladesh - indicate risk of envenomation by B. niger throughout the low and intermediate elevations of Nepal up to at least 1,500 m above sea level. As very few people in Nepal bring killed snakes to healthcare centers and because there is a general belief among local people that there are no kraits in the hills, bites by B. niger are likely to be misdiagnosed and underreported.(AU)

Leucoencefalopatía tóxica fatal: tres casos asociados al consumo de pasta base de cocaína / Fatal toxic leukoencephalopathy associated with consumption of pasta base of cocaine: Report of three cases

The prevalence of drug-associated toxic encephalopathy is unknown, but it is an uncommon condition. Toxic leukoencephalopathy was described associated with heroin consumption, it has been less commonly described with the use of cocaine and there are no reports of its association with consumption pasta base of cocaine (PBC). We report two females aged 31 years and a male aged 19 years, consumers of PBC who developed a fatal toxic leukoencephalopathy. They initiated their disease with severe and persistent headache, sequential focal neurologic deficits and a progressive impairment of consciousness that culminated with their death. Laboratory parameters such as blood count, cerebrospinal fluid analyses or infectious biological indices were normal. MRI showed multifocal lesions in brain white matter of both hemispheres confirming the leukoencephalopathy. There was no response to the use of methylprednisolone.

Relationship between Quality of Life and Nurse-led Bedside Symptom Evaluations in Patients with Chemotherapy-induced Peripheral Neuropathy

PURPOSE: This cross-sectional study aimed at determining the relationship between patient-reported quality of life (QOL) and nurse-led bedside evaluations of chemotherapy-induced peripheral neuropathy symptoms. METHODS: One hundred ninety-five patients treated at the oncology clinic at our institution were assessed using Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity and nurse-led bedside examinations. The relationship between self-reported QOL and bedside examinations was evaluated using Spearman rank correlations. RESULTS: Scores of upper and lower extremity muscle strength based on the bedside examinations showed a weak negative correlation with the emotional well-being subscale of Functional Assessment of Cancer Therapy-General. Further, weak negative relationships were present between QOL and the following nurse-reported parameters: vibration perception in the hand, upper extremity muscle strength, touch and vibration perception in the feet, and tendon reflexes. CONCLUSION: Collectively, our results indicate that nurse-led bedside evaluation is a noninvasive and useful method for detecting neurotoxicity and evaluating the patient's QOL both during and after treatment.

Abordagem inicial no atendimento ambulatorial em distúrbios neurotoxicológicos: parte III - solventes orgânicos / Initial approach to outpatient treatment of neurotoxicological disorders: Part III – organic solvents

Introdução: Milhões de pessoas são expostas diariamente aos solventes. Inúmeros solventes podem causar intoxicação aguda. Menos clara é a associação da exposição crônica e em baixas doses poder produzir alteração neurológica. Diversas atividades ocupacionais estão envolvidas com a sua exposição. Condição bastante diferente é o seu uso inadvertido com intuito alucinógeno. Método: Trata-se de revisão atualizada da literatura a partir de pesquisa na base de dados MEDLINE e LILACS. Também utilizou-se livros e documentos publicados em formato eletrônico.Discussão: Distúrbios neuromusculares, distúrbios do movimento, alterações cognitivo-comportamentais e neurofisiológicas têm sido relacionados a inúmeros agentes tóxicos nos últimos anos. A proposta deste artigo é revisar os principais distúrbios neurológicos associados à exposição crônica por solventes orgânicos. A fim de facilitar a abordagem inicial no atendimento ambulatorial aos distúrbios neurotoxicológicos foram confeccionadas tabelas descrevendo os principais agentes tóxicos, as fontes de exposição envolvidas e suas principais manifestações neurológicas. Conclusão: Tolueno, bissulfeto de carbono e n-Hexano são alguns solventes envolvidos nos distúrbios neurotoxicológicos, Contudo, fica evidente nesta revisão que são necessários novos estudos a fim de determinar a real associação destes e outros solventes nos distúrbios crônicos do sistema nervoso central e periférico.

Introduction: Millions of peoples are exposed to solvents every day. Most solvents cause acute intoxication. Less evident is the association of chronic exposure and in low doses in producing neurological disorders. Innumerable occupational activities are involved in the exposure to solvents. Their inadvertent use with hallucinogenous intention is an entirely different condition. Method: The method consists of an updated review of the literature based on research in the MEDLINE and LILACS databases, as well as books and documents published online. Discussion: Neuromuscular disorders, movement disorders, cognitive-behavioral and neurophysiological changes have been attributed to innumerable toxic agents in recent years. This article proposes to review the main neurological disorders associated with chronic exposure to organic solvents. To facilitate the initial approach to treatment of neurotoxicological disorders of outpatient, tables were devised to describe the main toxic agents, the sources of exposure involved and their main neurological manifestations. Conclusions: Toluene, carbon bisulfate and n-hexane are some of the solvents involved in neurotoxicological disorders. However, this review reveals the need for new studies to determine the real association of these and other solvents in chronic disorders of the central and peripheral nervous systems.

Abordagem inicial no atendimento ambulatorial em distúrbiosneurotoxicológicos. Parte II - agrotóxicos / Initial approach to outpatient treatment of neurotoxicological disorders. Part II – pesticides

Introdução: A venda de agrotóxicos no Brasil representa 86% do mercado consumidor da América Latina, com um faturamento anual que chega a US$ 7 bilhões. O desconhecimento e a falta de percepção dos riscos inerentes a utilização dessas substâncias é constatada com frequência aumentando as chances de intoxicação por tais agentes. Métodos: Trata-se de revisão atualizada da literatura a partir de pesquisa na base de dados MEDLINE e LILACS. Também utilizaram-se livros e documentos publicados em formato eletrônico. Resultados e discussão: Distúrbios neuromusculares, distúrbios do movimento, alterações cognitivo-comportamentais e neurofisiológicas têm sido relacionados a inúmeros agentes tóxicos nos últimos anos. A proposta deste artigo é revisar os principais distúrbios neurológicos associados à exposição crônica por agrotóxicos. A fim de facilitar a abordagem inicial no atendimento ambulatorial aos distúrbios neurotoxicológicos foram confeccionadas tabelas descrevendo os principais agentes tóxicos, as fontes de exposição envolvidas e suas principais manifestações neurológicas. Conclusão: Inseticidas, herbicidas, fungicidas e fumigantes são alguns agrotóxicos envolvidos nos distúrbios neurotoxicológicos. Contudo, fica evidente nesta revisão que são necessários novos estudos a fim de determinar a real associação destes e outros agrotóxicos nos distúrbios crônicos do sistema nervoso central e periférico.

Introduction: The sale of pesticides in Brazil represents 86% of the Latin American consumer market, with annual revenues reachingup to US$ 7 billion. Lack of knowledge and unawareness of the risks inherent to the use of these substances is frequently found, increasingthe possibility of intoxication by these agents. Methods: The method consists of an updated review of the literature based on research in theMEDLINE and LILACS databases, as well as books and documents published online. Results and discussion: Neuromusculardisorders, movement disorders, cognitive-behavioral and neurophysiologic alterations have been attributed to innumerable toxic agents in recentyears. This article proposes to review the main neurological disorders associated with chronic exposure to pesticides. To make easy the initialapproach to outpatient treatment of neurotoxicological disorders, tables were devised to describe the main toxic agents, the sources of exposureinvolved and their main neurological manifestations. Conclusion: Insecticides, herbicides, fungicides and fumigants are some of the pesticides involved in neurotoxicological disorders. However, this review reveals the need for new studies to determine the real association of these and other pesticides in chronic disorders of the central and peripheral nervous systems.

Aspectos clínicos da intoxicação experimental pelas favas de Stryphnodendron fissuratum (Leg. Mimosoideae) em caprinos / Clinical aspects of the experimental poisoning by the pods of Stryphnodendron fissuratum (Leg. Mimosoideae) in goats

Com o objetivo de caracterizar o quadro clínico da intoxicação por Stryphnodendron fissuratum Mart. (Leg. Mimosoideae) em caprinos, administraram-se as favas dessa planta a oito caprinos, por via oral forçada em doses únicas e a outros dois caprinos, em doses fracionadas. A menor dose que causou sinais clínicos e morte foi a de 10g/kg. Doses de 20g/kg e 40g/kg causaram sinais acentuados e doses únicas de 5g/kg não provocaram sinais. Doses fracionadas de 5g/kg durante quatro dias, totalizando 20g/kg provocaram sinais acentuados e morte. Em ambos os grupos, os primeiros sinais de intoxicação foram observados a partir do primeiro dia de experimento e a evolução variou de 4-25 dias. A doença caracterizou-se principalmente por alterações digestórias e nervosas que consistiram em anorexia, desidratação, hipomotilidade e atonia ruminal, timpanismo, gemidos constantes, dor à percussão abdominal, fezes com muco, ranger de dentes, apatia, ataxia, dismetria, tremores de cabeça, tremores musculares, fraqueza com o andar cambaleante e trôpego, acentuada depressão e decúbito esternal ou lateral prolongado e morte. Alguns animais apresentaram acentuada queda de pêlos na região dorsal; apenas um caprino apresentou fezes líquidas, marrom-escuras e fétidas. Outros sinais incluíram perda de fluido ruminal durante a ruminação, sialorréia, exsudato nasal seroso e lacrimejamento. As provas de função hepática e renal revelaram alterações discretas. As concentrações séricas de aspartato aminotransferase encontraram-se levemente aumentadas e as de creatinofosfocinase muito aumentadas.

In order to confirm the susceptibility of goats to the poisoning by Stryphnodendron fissuratum Mart. (Leg. Mimosoideae) and to characterize the clinical disease, the pods of the plant were given orally to each of eight young goats and in fractioned doses to other two. The lowest lethal dose was 10g/kg. The same dose was the lowest that induced disease. Doses of 20g/kg and 40g/kg caused pronounced clinical signs and doses of 5g/kg did not caused signs. Fractioned doses of 5g/kg during four days also caused pronounced signs. In each groups the first signs of poisoning were observed from the first day of experiments and the changes ranged from 4-25 days. The disease was characterized mainly by digestive and nervous disorders. Clinical signs were partial to complete anorexia, dehydration, decrease in ruminal activity up to atonia, tympanism, constant vocalizations, grinding of the teeth pain up on abdominal palpation, apathy, ataxia, depression, dysmetria, head and muscle tremors, weakness, difficulty in rising, sternal or lateral recumbency and death. Some goats presented extense hair loss in the skin of the dorsum; one goat presented liquid and black fetid feces. Other signs included loss of ruminal fluid during rumination, drooling, serous nasal and ocular discharges. Liver and kidney function tests had resulted in slight changes. AST serum levels were slightly increased and creatine phosphokinase levels were highly increased. These changes can associated to the effects of triterpenic saponins contained in the S. fissuratum pods.

Aspectos clínicos da intoxicação experimental pelas favas de Stryphnodendron fissuratum (Leg. Mimosoideae) em caprinos / Clinical aspects of the experimental poisoning by the pods of Stryphnodendron fissuratum (Leg. Mimosoideae) in goats

Com o objetivo de caracterizar o quadro clínico da intoxicação por Stryphnodendron fissuratum Mart. (Leg. Mimosoideae) em caprinos, administraram-se as favas dessa planta a oito caprinos, por via oral forçada em doses únicas e a outros dois caprinos, em doses fracionadas. A menor dose que causou sinais clínicos e morte foi a de 10g/kg. Doses de 20g/kg e 40g/kg causaram sinais acentuados e doses únicas de 5g/kg não provocaram sinais. Doses fracionadas de 5g/kg durante quatro dias, totalizando 20g/kg provocaram sinais acentuados e morte. Em ambos os grupos, os primeiros sinais de intoxicação foram observados a partir do primeiro dia de experimento e a evolução variou de 4-25 dias. A doença caracterizou-se principalmente por alterações digestórias e nervosas que consistiram em anorexia, desidratação, hipomotilidade e atonia ruminal, timpanismo, gemidos constantes, dor à percussão abdominal, fezes com muco, ranger de dentes, apatia, ataxia, dismetria, tremores de cabeça, tremores musculares, fraqueza com o andar cambaleante e trôpego, acentuada depressão e decúbito esternal ou lateral prolongado e morte. Alguns animais apresentaram acentuada queda de pêlos na região dorsal; apenas um caprino apresentou fezes líquidas, marrom-escuras e fétidas. Outros sinais incluíram perda de fluido ruminal durante a ruminação, sialorréia, exsudato nasal seroso e lacrimejamento. As provas de função hepática e renal revelaram alterações discretas. As concentrações séricas de aspartato aminotransferase encontraram-se levemente aumentadas e as de creatinofosfocinase muito aumentadas.

In order to confirm the susceptibility of goats to the poisoning by Stryphnodendron fissuratum Mart. (Leg. Mimosoideae) and to characterize the clinical disease, the pods of the plant were given orally to each of eight young goats and in fractioned doses to other two. The lowest lethal dose was 10g/kg. The same dose was the lowest that induced disease. Doses of 20g/kg and 40g/kg caused pronounced clinical signs and doses of 5g/kg did not caused signs. Fractioned doses of 5g/kg during four days also caused pronounced signs. In each groups the first signs of poisoning were observed from the first day of experiments and the changes ranged from 4-25 days. The disease was characterized mainly by digestive and nervous disorders. Clinical signs were partial to complete anorexia, dehydration, decrease in ruminal activity up to atonia, tympanism, constant vocalizations, grinding of the teeth pain up on abdominal palpation, apathy, ataxia, depression, dysmetria, head and muscle tremors, weakness, difficulty in rising, sternal or lateral recumbency and death. Some goats presented extense hair loss in the skin of the dorsum; one goat presented liquid and black fetid feces. Other signs included loss of ruminal fluid during rumination, drooling, serous nasal and ocular discharges. Liver and kidney function tests had resulted in slight changes. AST serum levels were slightly increased and creatine phosphokinase levels were highly increased. These changes can associated to the effects of triterpenic saponins contained in the S. fissuratum pods.

Isolation of Salmonella enterica serotype Isangi from a suspected case of enteric encephalopathy.

Nontyphoidal salmonella species are thought to be potentially infectious to humans and many are documented to cause human diseases. We isolated S. Isangi from the blood of a 30-year-old man with complaints of diarrhoea, fever, and altered sensorium. The serotype of the isolate was confirmed at National Salmonella Centre (Vet.), Division of Bacteriology and Mycology, Indian Veterinary Research Institute, Izzatnagar, India. The isolate was not an extended spectrum beta-lactamase (ESBL) producer and the patient responded well to ceftriaxone. We reviewed the literature concerning infections caused by salmonella; however, did not find any report related to S. Isangi infection in human beings from India.

Usefulness of Color Vision Test for Early Detection of Neurological Damages by Neurotoxic Substances / 예방의학회지

This paper reviews the published literature that is concerned with color vision impairment from industrial and environmental exposure to neurotoxic substances, and we evaluated whether testing for color vision impairment could be an affordable procedure for assessing these neurotoxic effects. In general, most cases of congenital color vision impairment are red-green, and blue-yellow impairment is extremely rare. However, most of the acquired color vision impairment that is related to age, alcohol or environmental factors is blue-yellow impairment. Therefore, many studies have been performed to identify this relationship between exposure to neurotoxic substances, such as organic solvents and heavy metals, and the prevalence of blueyellow color vision impairment. The test for color vision impairment is known to be very sensitive to the early signs of nervous system dysfunction and this can be useful for making the early diagnosis of neurotoxic effects from exposure to very low concentrations of toxic substances.

Toxic encephalopathy and noise-induced hearing loss.

In several laboratory animal studies, it has been documented that the hearing, vision, and brain can be injured due to exposure to organic solvents. This finding formed the background for a pilot study (n=16) aimed at identifying new ways of qualifying diagnostics, treatment, and rehabilitation of patients suffering from brain injury due to exposure to organic solvents, also referred to as toxic encephalopathy. Diagnosing toxic encephalopathy is complicated because the symptoms of this type of diffuse brain injury are non-specific. So, it was initially hypothesised that some of the difficulties involved in diagnosing toxic encephalopathy could be minimized by extending the diagnostic procedure. Apart from clinical interviewing and neuropsychological testing, the diagnosis should include the examination of hearing and vision. This will help in achieving new measures that could improve in diagnosing toxic encephalopathy with more certainty. On the basis of ranking, only one patient in the pilot study was considered to have a normal neuropsychological test profile, which was defined as a test profile without any marked deviations when compared with a normal population. A total of 10 patients were considered to have "discrete problems." These patients had a test profile showing either a few strikingly negative results or an array of results slightly below the expected level when compared with a normal population. A total of four patients were considered to suffer from "moderate problems" and one patient from "severe problems." The patients with "moderate problems" and "severe problems" showed consistent negative results and an unambiguous negative test profile. However, the overall results of all neuropsychological examinations performed revealed a dispersed picture. Quite remarkably, all the 13 patients who had their hearing examined showed a loss of hearing, 7 patients complained about tinnitus, and all patients had a history of exposure to both noise and organic solvents, which had not been observed at the initial examination, but seemed to have serious implications for their prognosis and future life.

Neurotoxicidad por solventes orgánicos, aspectos neurológicos y neurofisiológicos / Neurotoxicity syndromes for organic solvents: Neurological aspects and presentation of cases

Se presenta una actualización de las principales manifestaciones neurológicas por exposición laboral a solventes orgánicos; de la forma como debe investigarse una posible fuente laboral de toxicidad y la utilización de los estudios neuropsicológicos y electrofisiológicos en su confirmación. Para terminar se propone un protocolo de investigación de toxicidad por solventes orgánicos de fácil aplicación en nuestro medio

Amitraz poisoning: clinical and laboratory findings.

Amitraz is an insecticide/acaricide of formamidine pesticides used worldwide to control ectoparasites in animals. Amitraz poisoning is a rare disorder characterized by central nervous system (CNS) and respiratory depression, bradycardia, hypotension, hypothermia, hyperglycemia,nausea and vomiting. Poisoning may occur either by oral inhalation and dermal route. In this study, we present seven pediatric patients with amitraz poisoning. The initial symptoms were unconsciousness, dizziness and vomiting; and emerged within 30-150 minutes. The length of stay in the intensive care unit (ICU) was between 18-62 hours.

Síntomas tempranos de neurotoxicidad por exposición prolongada a plaguicidas / Early symptoms of neurotoxicity by lengthy exposure to pesticides

Es un diseño descriptivo de corte transversal, clínico epidemiológico, realizado entre diciembre 2000 - septiembre 2001. Con una muestra no probabilística, 28 agricultores voluntarios, género masculino, una edad promedio de 29 años, habitantes de la comunidad Gabante, Municipio Tovar, Estado Aragua, Venezuela. Un proceso de trabajo similar, dedicados al cultivo de durazno diez (10) horas diarias, lunes a sábado. Exposición a plaguicidas de 11 a 15 años. Un nivel de escolaridad (42.9 por ciento) de primaria incompleta. La entrevista clínico psicológica comprendió: historia de salud, historia laboral, antecedentes patológicos - neurológicos y antecedentes patológicos - psiquiátricos. Los resultados mostraron que los síntomas padecidos en los últimos tres meses mareos un 39 por ciento. Los hábitos psicobiológicos, alcohol (100 por ciento) y tabaco (42 por ciento) arrojaron porcentajes resaltantes. Las pruebas neuropsicológicas, Benton, PFN y destreza manual calificaron con resultados apreciables. El análisis estadístico se realizó con el PSICOTOX que clasificó el 72 por ciento tipo 2 o dudosos y el EPI-INFO 2000.

Metrondazole-induced neurotoxicity.

A 50 year old male with history of prolonged intake of metronidazole for treatment of liver abscess developed acute ataxia, disorientation, distal symmetrical sensory and proximal motor neuropathy. Patients being treated with metronidazole particularly those on high doses for prolonged period should be monitored for neurotoxicity.

A Case of Neurotoxicity Following 5-Fluorouracil-based Chemotherapy

5-Fluorouracil (5-FU) is a commonly used chemotherapeutic agent. However, its neurotoxicity is rare and not well recognized. We report a case of 5-FU neurotoxicity with organic brain syndrome and progression to multifocal leukoencephalopathy in a 44-year-old male patient having malignant gast- rointestinal stromal tumor. 5-FU-induced neurotoxicity should, therefore, be considered as an important differential diagnosis in cancer patients with neurological abnormality and history of chemotherapy.

Lidocaína en bajas dosis más fentanilo subaracnoidea: ausencia de irritación radicular transitoria / Low dose of lidocaine solution plus fentanyl: absent of transient radicular irritation

Antecedentes: El uso de lidocaína espinal está asociado a irritación radicular transitoria. La neurotoxicidad no está medida por su baricidad, pero podría ser dosis-dependiente. Sin embargo, se ha observado que la disminución de la concentración de lidocaína del 5 por ciento al 2 por ciento no disminuye la incidencia de síntomas neurológicos transitorios. Objetivo: El objetivo del presente estudio fue detarminar si usando dosis y concentraciones aún más bajas de lidocaína (40 mg - 1,6 por ciento) disminuye la incidencia de estos síntomas. Se la comparó con bupivacaína (10 mg - 0,4 por ciento); ambos anestésicos con 25 µg de fentanilo. Lugar de aplicación: Hospital Privado de Comunidad, Mar del Plata, Argentina. Diseño: estudio clínico prospectivo. Población: Se estudiaron prospectivamente 50 pacientes de ambos sexos, ASA I-III, distribuidos aleatoriamente en dos grupos según el anestésico local recibido: lidocaína (n = 26) y bupivacaína (n = 24), que ingresaron a quirófano para la realización de hernioplastias o eventroplastias en régimen ambulatorio. Métodos: se evaluó la presencia de irritación radicular transitoria en el postoperatorio. Resultados: Ninguno de los pacientes de los 2 grupos tuvieron síntomas de irritación radicular. Conclusiones: Estos resultados no concuerdan con estudios previos; concluimos que 40 mg de lidocaína al 1,6 por ciento con 25 µg de fentanilo no producen irritación radicular transitoria en las primeras 48 horas postoperatorias.