Towards better antivenoms: navigating the road to new types of snakebite envenoming therapies

Abstract Snakebite envenoming is a significant global health challenge, and for over a century, traditional plasma-derived antivenoms from hyperimmunized animals have been the primary treatment against this infliction. However, these antivenoms have several inherent limitations, including the risk of causing adverse reactions when administered to patients, batch-to-batch variation, and high production costs. To address these issues and improve treatment outcomes, the development of new types of antivenoms is crucial. During this development, key aspects such as improved clinical efficacy, enhanced safety profiles, and greater affordability should be in focus. To achieve these goals, modern biotechnological methods can be applied to the discovery and development of therapeutic agents that can neutralize medically important toxins from multiple snake species. This review highlights some of these agents, including monoclonal antibodies, nanobodies, and selected small molecules, that can achieve broad toxin neutralization, have favorable safety profiles, and can be produced on a large scale with standardized manufacturing processes. Considering the inherent strengths and limitations related to the pharmacokinetics of these different agents, a combination of them might be beneficial in the development of new types of antivenom products with improved therapeutic properties. While the implementation of new therapies requires time, it is foreseeable that the application of biotechnological advancements represents a promising trajectory toward the development of improved therapies for snakebite envenoming. As research and development continue to advance, these new products could emerge as the mainstay treatment in the future.

Venomous animals in Pernambuco: children at risk / Animais peçonhentos em Pernambuco: crianças em risco

Abstract Objectives: to analyze the epidemiological and clinical aspects of accidents caused by venomous animals in children under 15 years old. Methods: a cross-sectional study with an analytical component using secondary data from Centro de Informação e Assistência Toxicológica de Pernambuco (CIATox-PE), (Poison Center in Pernambuco)), in 2017 to 2019. Notifications of accidents caused were included in the studied age group and evaluated the characteristics of poisoning (animal classification, exposure zone, place and time of the occurrence and specific use of serum therapy), and of the patient (sociodemographic variables, clinical condition and evolution). The analysis performed in STATA® 13.1 presents frequency distribution tables and Pearson's chi-square for comparison. Results: of the 2678 notifications, 82,8% were scorpionism and 10, 8% snakebite. The age group of1 to 9 years old (70.5%) and being male (54.1%) were predominant. Most of the cases occurred in urban area (80.9%), in Recife (67.3%), inside the victim's residence (83.9%) and at night (47.3%). The majority (87.1%) were classified as 'mild severity', 10% received antivenom therapy and one died (by scorpionism). Two cases of snakebite in the workplace were registered. Conclusion: there was a high frequency of accidents caused in the urban area, which may be related to the lack of urban planning and sanitary education. The accidents caused among children in the household environment and the suspicion of child labor in the age group of 10 to 14 years old were also highlighted which favors the development and habits of the venomous animal.

Resumo Objetivos: analisar aspectos epidemiológicos e clínicos dos acidentes por animais peçonhentos em menores de 15 anos. Métodos: estudo transversal com componente analítico utilizando dados secundários do Centro de Informação e Assistência Toxicológica de Pernambuco (CIATox-PE), no período de 2017 a 2019. Foram incluídas as notificações dos acidentes na faixa etária estudada e avaliadas características do envenenamento (classe do animal, zona de exposição, local/turno da ocorrência e uso soroterapia específica) e do paciente (variáveis sociodemográficas, gravidade clínica e evolução). A análise realizada no STATA® 13.1 apresenta tabelas de distribuição de frequência e qui-quadrado de Pearson para comparação. Resultados: das 2678 notificações, 82,8% foram de escorpionismo e 10,8% de ofidismo. Predominaram na faixa etária de 1a 9 anos (70,5%) e sexo masculino (54,1%);ocorreram principalmente na zona urbana (80,9%),no Recife(67,3%), na residência da vítima (83,9%), durante horário noturno (47,3%). A maioria (87,1%) foi classificada como de gravidade leve, 10% receberam soroterapia e ocorreu um óbito (escorpionismo). Registraram-se dois casos de ofidismo em ambiente de trabalho. Conclusão: ressaltam-se os acidentes intradomiciliares entre crianças e a suspeita de trabalho infantil na faixa etária de 10 a 14anos.Os acidentes ocorreram sobretudo na zona urbana provavelmente associado à falta de planejamento e educação sanitária que favorece o desenvolvimento e hábitos do animal peçonhento.

Epidemiological aspects of scorpionic accidents in a municipality in Brazil's northeastern / Aspectos epidemiológicos dos acidentes escorpiônicos em um munícipio do nordeste brasileiro

Scorpionic accidents are a major public health problem due to the high occurrence with potential seriousness. In this manner, the research aimed to analyze the occurrence of scorpionic accidents in a municipality in the northeastern of Brazil. An exploratory, descriptive study was made, with a quantitative approach, using secondary data which was gotten from the Notifiable Diseases Information System (SINAN), from 2008 to 2018. Data such as neighborhood, presence of street markets were also used, and the existence of sanitation and climatic data such as temperature and season. Geoprocessing was used to identify possible changes in the environment. In the analyzed period, 9,330 cases of scorpion accidents were recorded, with an average of 848 annual notifications. Scorpionic accidents occurred more frequently in women (5,686; 60.94%). Individuals aged 20 to 29 years (1.727; 18.51%) were more frequent to scorpion stings. Regarding the body parts where the stings were made, the highlights were on the foot (3.515; 37.67%) followed by the hand (2.818; 30.20%). No statistically significant relation was observed between climatic factors and scorpionic accidents. However, the high number of cases of scorpionic accidents was observed in the last 11 years studied. It was evident that during the study period there was no statistical relationship when climatic factors were correlated to scorpionic accidents. On its turn, when it was verified the results of the geoprocessing analysis, it was seen that anthropic factors have been motivating the potentiation of the occurrence of these accidents.

Os acidentes escorpiônicos apresentam-se como um grande problema de saúde pública em virtude da grande ocorrência com potencial gravidade. Nesse sentido, o trabalho teve como objetivo analisar a ocorrência de acidentes escorpiônicos em um município do nordeste brasileiro. Foi realizado um estudo descritivo, de caráter exploratório, com abordagem quantitativa em que foram utilizados dados secundários obtidos no Sistema de Informação de Agravos de Notificação (SINAN), no período de 2008 a 2018. Também foram utilizados dados como bairro, presença de feiras livres e a existência de saneamento básico e dados climáticos como temperatura e estação do ano. O geoprocessamento foi utilizado para identificar as possíveis alterações no ambiente. No período analisado, foram registrados 9,330 casos de acidentes com escorpião, com média de 848 notificações anuais. Os acidentes escorpiônicos ocorreram com mais frequência em mulheres (5,686; 60,94%). Em indivíduos na faixa etária de 20 a 29 anos (1,727; 18,51%) foram mais frequentes a picada de escorpião. Com relação ao local das picadas destacaram-se o pé (3,515; 37,67%), seguido da mão (2,818; 30,20%). Não foi observada relação estatisticamente significativa entre os fatores clímáticos e os acidentes escorpiônicos. Foi observado elevado número de casos de acidentes escorpiônicos nos últimos 11 anos estudados. Ficou evidente que durante o período de estudo não existiu relação estatística quando se correlacionou fatores climáticos aos acidentes escorpiônicos. Por sua vez, ao verificar os resultados da análise de geoprocessamento foi visto que fatores antrópicos têm sido motivadores da potencialização da ocorrência desses acidentes.

Epidemiological aspects of scorpionic accidents in a municipality in Brazil's northeastern / Aspectos epidemiológicos dos acidentes escorpiônicos em um munícipio do nordeste brasileiro

Scorpionic accidents are a major public health problem due to the high occurrence with potential seriousness. In this manner, the research aimed to analyze the occurrence of scorpionic accidents in a municipality in the northeastern of Brazil. An exploratory, descriptive study was made, with a quantitative approach, using secondary data which was gotten from the Notifiable Diseases Information System (SINAN), from 2008 to 2018. Data such as neighborhood, presence of street markets were also used, and the existence of sanitation and climatic data such as temperature and season. Geoprocessing was used to identify possible changes in the environment. In the analyzed period, 9,330 cases of scorpion accidents were recorded, with an average of 848 annual notifications. Scorpionic accidents occurred more frequently in women (5,686; 60.94%). Individuals aged 20 to 29 years (1.727; 18.51%) were more frequent to scorpion stings. Regarding the body parts where the stings were made, the highlights were on the foot (3.515; 37.67%) followed by the hand (2.818; 30.20%). No statistically significant relation was observed between climatic factors and scorpionic accidents. However, the high number of cases of scorpionic accidents was observed in the last 11 years studied. It was evident that during the study period there was no statistical relationship when climatic factors were correlated to scorpionic accidents. On its turn, when it was verified the results of the geoprocessing analysis, it was seen that anthropic factors have been motivating the potentiation of the occurrence of these accidents.

Os acidentes escorpiônicos apresentam-se como um grande problema de saúde pública em virtude da grande ocorrência com potencial gravidade. Nesse sentido, o trabalho teve como objetivo analisar a ocorrência de acidentes escorpiônicos em um município do nordeste brasileiro. Foi realizado um estudo descritivo, de caráter exploratório, com abordagem quantitativa em que foram utilizados dados secundários obtidos no Sistema de Informação de Agravos de Notificação (SINAN), no período de 2008 a 2018. Também foram utilizados dados como bairro, presença de feiras livres e a existência de saneamento básico e dados climáticos como temperatura e estação do ano. O geoprocessamento foi utilizado para identificar as possíveis alterações no ambiente. No período analisado, foram registrados 9,330 casos de acidentes com escorpião, com média de 848 notificações anuais. Os acidentes escorpiônicos ocorreram com mais frequência em mulheres (5,686; 60,94%). Em indivíduos na faixa etária de 20 a 29 anos (1,727; 18,51%) foram mais frequentes a picada de escorpião. Com relação ao local das picadas destacaram-se o pé (3,515; 37,67%), seguido da mão (2,818; 30,20%). Não foi observada relação estatisticamente significativa entre os fatores climáticos e os acidentes escorpiônicos. Foi observado elevado número de casos de acidentes escorpiônicos nos últimos 11 anos estudados. Ficou evidente que durante o período de estudo não existiu relação estatística quando se correlacionou fatores climáticos aos acidentes escorpiônicos. Por sua vez, ao verificar os resultados da análise de geoprocessamento foi visto que fatores antrópicos têm sido motivadores da potencialização da ocorrência desses acidentes.

Epidemiological aspects of scorpionic accidents in a municipality in Brazils northeastern

Abstract Scorpionic accidents are a major public health problem due to the high occurrence with potential seriousness. In this manner, the research aimed to analyze the occurrence of scorpionic accidents in a municipality in the northeastern of Brazil. An exploratory, descriptive study was made, with a quantitative approach, using secondary data which was gotten from the Notifiable Diseases Information System (SINAN), from 2008 to 2018. Data such as neighborhood, presence of street markets were also used, and the existence of sanitation and climatic data such as temperature and season. Geoprocessing was used to identify possible changes in the environment. In the analyzed period, 9,330 cases of scorpion accidents were recorded, with an average of 848 annual notifications. Scorpionic accidents occurred more frequently in women (5,686; 60.94%). Individuals aged 20 to 29 years (1.727; 18.51%) were more frequent to scorpion stings. Regarding the body parts where the stings were made, the highlights were on the foot (3.515; 37.67%) followed by the hand (2.818; 30.20%). No statistically significant relation was observed between climatic factors and scorpionic accidents. However, the high number of cases of scorpionic accidents was observed in the last 11 years studied. It was evident that during the study period there was no statistical relationship when climatic factors were correlated to scorpionic accidents. On its turn, when it was verified the results of the geoprocessing analysis, it was seen that anthropic factors have been motivating the potentiation of the occurrence of these accidents.

Resumo Os acidentes escorpiônicos apresentam-se como um grande problema de saúde pública em virtude da grande ocorrência com potencial gravidade. Nesse sentido, o trabalho teve como objetivo analisar a ocorrência de acidentes escorpiônicos em um município do nordeste brasileiro. Foi realizado um estudo descritivo, de caráter exploratório, com abordagem quantitativa em que foram utilizados dados secundários obtidos no Sistema de Informação de Agravos de Notificação (SINAN), no período de 2008 a 2018. Também foram utilizados dados como bairro, presença de feiras livres e a existência de saneamento básico e dados climáticos como temperatura e estação do ano. O geoprocessamento foi utilizado para identificar as possíveis alterações no ambiente. No período analisado, foram registrados 9,330 casos de acidentes com escorpião, com média de 848 notificações anuais. Os acidentes escorpiônicos ocorreram com mais frequência em mulheres (5,686; 60,94%). Em indivíduos na faixa etária de 20 a 29 anos (1,727; 18,51%) foram mais frequentes a picada de escorpião. Com relação ao local das picadas destacaram-se o pé (3,515; 37,67%), seguido da mão (2,818; 30,20%). Não foi observada relação estatisticamente significativa entre os fatores clímáticos e os acidentes escorpiônicos. Foi observado elevado número de casos de acidentes escorpiônicos nos últimos 11 anos estudados. Ficou evidente que durante o período de estudo não existiu relação estatística quando se correlacionou fatores climáticos aos acidentes escorpiônicos. Por sua vez, ao verificar os resultados da análise de geoprocessamento foi visto que fatores antrópicos têm sido motivadores da potencialização da ocorrência desses acidentes.

Acute kidney injury caused by venomous animals: inflammatory mechanisms

Abstract Either bites or stings of venomous animals comprise relevant public health problems in tropical countries. Acute kidney injury (AKI) induced by animal toxins is related to worse prognostic and outcomes. Being one the most important pathways to induce AKI following envenoming due to animal toxins, inflammation is an essential biological response that eliminates pathogenic bacteria and repairs tissue after injury. However, direct nephrotoxicity (i.e. apoptotic and necrotic mechanisms of toxins), pigmenturia (i.e. rhabdomyolysis and hemolysis), anaphylactic reactions, and coagulopathies could contribute to the renal injury. All these mechanisms are closely integrated, but inflammation is a distinct process. Hence, it is important to improve our understanding on inflammation mechanisms of these syndromes to provide a promising outlook to reduce morbidity and mortality. This literature review highlights the main scientific evidence of acute kidney injury induced by bites or stings from venomous animals and their inflammatory mechanisms. It included observational, cross-sectional, case-control and cohort human studies available up to December 2019. Descriptors were used according to Medical Subject Headings (MeSH), namely: Acute kidney injury or Venom and Inflammation on Medline/Pubmed and Google Scholar; Kidney disease or Acute kidney injury on Lilacs and SciELO. The present review evidenced that, among the described forms of renal inflammation, it can occur either directly or indirectly on renal cells by means of intravascular, systemic and endothelial hemolysis, activation of inflammatory pathway, as well as direct action of venom cytotoxic components on kidney structures.

Epidemiology of snakebites in Colombia (2008-2016) / Epidemiología de las mordeduras por serpientes en Colombia (2008-2016)

ABSTRACT Objective To describe the main epidemiological features of snakebites in Colombia during the period 2008 to 2016. Methods A retrospective (quantitative) descriptive analytical empirical study was carried out, based on the official databases of the Public Health Surveillance in the Integral Information System of the Social Protection (SISPRO) and the Surveillance System in Public Health (Sivigila) of the reported cases of snakebites in Colombia for that period. Results In total, 37 066 cases were reported, with annual incidences ranging from 7.0 (2008) to 9.7 (2011 and 2012) cases per 100,000 population. Mortality rates ranged from 0.059 (2013) to 0.091 (2011) deaths per 100 000 population, with case fatality rates ranging from 0.6% (2013) to 1.0% (2010). Indigenous and Afro-Colombian populations were highly affected, and highest incidences occurred in males, and in people living in rural areas. The average age of affected people is 31.7 years (95% CI 28.3 34.5). The regions with higher incidence are Amazonia and Orinoquia. Species of the genus Bothrops are responsible for the highest number of bites (64.5%), owing to their wide distribution in Colombia. Regarding clinical manifestations, pain and edema were observed in 86.9% and 78.8% of patients, respectively. Cellulitis and abscesses were the most frequent local complications of these envenomings. Conclusions Results underscore the relevance of snakebite envenoming in Colombia, and provide information for improving the public health attention to these envenoming.(AU)

RESUMEN Objetivo Describir las principales características epidemiológicas de las mordeduras por serpientes en Colombia durante el período 2008-2016. Métodos Se realizó un estudio retrospectivo (cuantitativo) analítico empírico sobre los reportes de accidentes por mordedura de serpientes en Colombia para el período 2008 a 2016, a partir de las bases de datos oficiales del Sistema Integral de Información de la Protección Social (SISPRO) y del Sistema Nacional de Vigilancia en Salud Pública (Sivigila). Resultados Se reportaron 37 066 casos de mordeduras por serpientes en ese período. Las incidencias anuales oscilaron entre 7,0 (2008) y 9,7 (2011 y 2012) casos por 100,000 habitantes. Las tasas de mortalidad oscilaron entre 0,059 (2013) y 0,091 (2011) muertes por 100 000 habitantes, con tasas de letalidad entre 0,6% (2013) y 1,0% (2010). Los grupos más afectados fueron las poblaciones indígenas y afrocolombianas, y las personas residentes en zonas rurales. La edad promedio de las personas afectadas fue 31,7 años (IC 95% 28,3 34,5). Las regiones con mayor incidencia fueron la Amazonía y la Orino-quía. Especies del género Bothrops fueron responsables del mayor número de casos (64,5%), debido a su amplia distribución en el territorio colombiano. Con relación a las manifestaciones clínicas, se describió dolor y edema en 86,9% y 78,8% de los pacientes, respectivamente. Las complicaciones locales más frecuentes fueron las celulitis y los abscesos. Conclusiones Los resultados muestran la importancia de las mordeduras por serpientes en Colombia y suministran información para mejorar la atención de la salud pública ante estos envenenamientos.(AU)

Injuries caused by fish to fishermen in the Vale do Alto Juruá, Western Brazilian Amazon

Abstract INTRODUCTION: This study aimed to document injuries caused by fish among professional fishermen in the Western Brazilian Amazon. METHODS: We undertook a descriptive, retrospective study, involving 51 professional fishermen, to determine clinical, epidemiological, and therapeutic aspects of their injuries. RESULTS: Among 51 fishermen interviewed, most injuries were due to mandi (Pimelodus spp.), and the hands were the most injured region, resulting in pain and bleeding in all cases. CONCLUSIONS: Our study findings confirm the morbidity of fish-related injuries, and reaffirm the need for relevant information regarding prevention and injury management.

Clinical assessment and pathophysiology of Bothrops venom-related acute kidney injury: a scoping review

Bothrops are one of the most common medically important snakes found in Latin America. Its venom is predominantly hemotoxic and proteolytic, which means that local lesion (edema and redness) and hemorrhagic symptoms are recurrent in envenoming by this snake. Although hemorrhage is usually the major cause of death, snakebite-related acute kidney injury is another potentially fatal clinical complication that may lead to chronic kidney disease. The present review highlights the main studies on Bothrops venom-related acute kidney injury, including observational, cross-sectional, case-control and cohort human studies available up to December 2019. The following descriptors were used according to Medical Subject Headings (MeSH): on Medline/Pubmed and Google Scholar "acute kidney injury" or "kidney disease" and "Bothrops"; on Lilacs and SciELO "kidney disease" or "acute kidney injury" and "Bothrops". Newcastle-Ottawa quality assessment scale was used to appraise the quality of the cross-sectional and cohort studies included. The selection of more severe patients who looked for health care units and tertiary centers is a risk of bias. Due to the methodological heterogeneity of the studies, a critical analysis of the results was performed based on the hypothesis that the design of the included studies influences the incidence of acute kidney injury. Fifteen human studies (total participants 4624) were included according to stablished criteria. The coagulation abnormalities (hemorrhagic symptoms, abnormal fibrinogen and activated partial thromboplastin time) were associated with acute kidney injury in the most recent studies reported. The findings observed in this review provide up-to-date evidence about the acute kidney injury pathogenesis following Bothrops syndrome. Studies pointed out that coagulation abnormalities comprise the major pathway for acute kidney injury development. This review may improve patient management by primary healthcare providers, allowing earlier diagnosis and treatment of Bothrops venom-related acute kidney injury.(AU)

Honey bee envenoming in Santa Catarina, Brazil, 2007 through 2017: an observational, retrospective cohort study

Abstract INTRODUCTION: We evaluated the epidemiological and clinical profile of reported cases of bee sting incidents in Santa Catarina, Brazil. METHODS: This retrospective cohort study included all reported cases of bee sting incidents among the population of Santa Catarina from 2007 to 2017. RESULTS: In total, 8,912 cases were reported, corresponding to an overall rate of 12.3/100,000 population. The mean age was 29,8 years with 60.2% men. The lethality rate was 0.2%. CONCLUSIONS: Santa Catarina has a high incidence rate of bee stings, which is higher than the national average. The data presented in this study may be underestimated.

True or false coral snake: is it worth the risk? A Micrurus corallinus case report

Bites provoked by the genus Micrurus represent less than 1% of snakebite cases notified in Brazil, a tiny fraction compared with other genus such as Bothrops and Crotalus, which together represent almost 80% of accidents. In addition to their less aggressive behavior, habits and morphology of coral snakes are determinant factors for such low incidence of accidents. Although Micrurus bites are rare, victims must be rescued and hospitalized in a short period of time, because this type of envenoming may evolve to a progressive muscle weakness and acute respiratory failure. Case Presentation We report an accident caused by Micrurus corallinus involving a 28-year-old Caucasian sailor man bitten on the hand. The accident occurred in a recreational camp because people believed the snake was not venomous. The victim presented neurological symptoms 2 h after the accident and was taken to the hospital, where he received antielapidic serum 10 h after the bite. After the antivenom treatment, the patient presented clinical evolution without complications and was discharged 4 days later. Conclusions: We reinforce that it is essential to have a health care structure suitable for the treatment of snakebite. Besides, the manipulation of these animals should only be carried out by a team of well-equipped and trained professionals, and even so with special attention.(AU)

True or false coral snake: is it worth the risk? A Micrurus corallinus case report

Background Bites provoked by the genus Micrurus represent less than 1% of snakebite cases notified in Brazil, a tiny fraction compared with other genus such as Bothrops and Crotalus, which together represent almost 80% of accidents. In addition to their less aggressive behavior, habits and morphology of coral snakes are determinant factors for such low incidence of accidents. Although Micrurus bites are rare, victims must be rescued and hospitalized in a short period of time, because this type of envenoming may evolve to a progressive muscle weakness and acute respiratory failure. Case Presentation We report an accident caused by Micrurus corallinus involving a 28-year-old Caucasian sailor man bitten on the hand. The accident occurred in a recreational camp because people believed the snake was not venomous. The victim presented neurological symptoms 2 h after the accident and was taken to the hospital, where he received antielapidic serum 10 h after the bite. After the antivenom treatment, the patient presented clinical evolution without complications and was discharged 4 days later. Conclusions We reinforce that it is essential to have a health care structure suitable for the treatment of snakebite. Besides, the manipulation of these animals should only be carried out by a team of well-equipped and trained professionals, and even so with special attention.

Complicaciones Neurológicas De Las Mordeduras De Arañas / Neurological Complications Of Spider Bites

Resumen Las arañas son artrópodos venenosos de distribución global. La mordedura de la mayoría de las arañas no tiene trascendencia clínica, debido a la dificultad que éstas tienen de inyectar veneno a los seres humanos por el pequeño tamaño de sus quelíceros. A pesar de esto, existen cientos de casos reportados con envenenamiento secundario a mordedura de arañas. El cuadro clínico es pleomórfico, aunque pueden distinguirse tres síndromes principales: latrodectismo, loxoscelismo y envenenamiento por la araña de "tela en embudo". El latrodectismo se debe a una neurotoxina llamada alfa-latrotoxina presente en el veneno de las "viudas negras" (latrodectus sp). El cuadro cursa con dolor intenso en el sitio de la mordedura, y la complicación sistémica más común es la hipertensión arterial. Las complicaciones neurológicas consisten en cefalea, letargia, irritabilidad, mialgias, temblor, fasciculaciones, ataxia o parestesias. Estas últimas se relacionan con liberación excesiva de neurotransmisores colinérgicos a nivel de la unión neuromuscular. El loxoscelismo es causado por arañas de la familia Sicariidae, géneros Loxosceles y Sicarius. Existen dos tipos de presentación, la cutánea (cambios limitados al área de piel afectada) y la víscerocutánea. En esta última, puede ocurrir coagulopatía severa, asociada o no a insuficiencia renal aguda, ictericia, fiebre, falla multiorgánica y shock. El veneno de las arañas "tela de embudo" tiene potentes neurotoxinas llamadas delta-atracotoxinas, las que simulan neurotransmisores liberados por vesículas pre-sinápticas, causando hiperestimulación de los receptores pos-sinápticos, lo que resulta en alteraciones sensitivas y parálisis muscular. También pueden desarrollarse alteraciones del sistema nervioso simpático y parasimpático, tales como diaforesis, sialorrea, hipotensión arterial y arritmias cardiacas.

Abstract Spiders are venomous arthropods with worldwide distribution. Most spider bites are clinically insignificant, as the size of their chelicerae is too small to inject enough amount of venom to human beings. Despite this, there are hundreds of reported cases of human envenoming related to spider bites. While clinical manifestations related to spider-bite envenoming are pleomorphic, three main clinical syndromes could be recognized: latrodectism, loxoscelism, and funnel-web spider envenoming. Latrodectism is caused by the potent neurotoxin (-latrotoxin present in the venom of widow spiders (Latrodectus sp.). Most cases present with severe pain at the site of the bite, with arterial hypertension being the most frequent systemic manifestation. Neurological complications mostly consist of headache, lethargy, irritability, generalyzed myalgia, tremor, fasciculations, ataxia, or paresthesias. The latter manifestations are related to an exhaustive release of cholinergic neurotransmitters at the neuromuscular junction. Loxoscelism is caused by envenoming by spiders of the family Sicariidae, genera Loxosceles and Sicarius. It presents in two different forms, cutaneous (with changes restricted to the affected skin) area and viscerocutaneous. In the latter, a severe coagulopathy may occur, associated or not with acute renal failure, jaundice, fever, multi-organ failure and shock. The venom of fennel-web spiders have potent neurotoxins, called (-atracotoxins, that stimulates neurotransmitter release from the presynaptic vesicle, causing hyperstimulation of post-synaptic receptors resulting in sensory disturbances and muscle paralysis. Also, sympathetic and parasympathetic manifestations, including diaphoresis, hypersalivation, arterial hypotension, and cardiac arrhythmias may occur.

Locked-in Syndrome Following a King Cobra (Ophiophagus hannah) Envenomation

Theincidence of envenoming from king cobra, Ophiophagus hannah in human is relatively rare. Its venom acts on the postsynaptic region of the neuromuscular junction causing descending flaccid paralysis. Locked-in syndrome is a clinical state of inability to provide motor response in a conscious patient. Many reported cases of locked-in syndrome following neurotoxic snake-bite mimics brain death. We report a case of a middle aged man who presented with progressive neurological deficit following a king cobra bite over his right arm. He had local and systemic neurotoxic envenoming. His condition deteriorated, and was intubated and ventilated in the emergency department. He received a total of 33 vials of the Ophiophagus hannah monospecific antivenom and subsequently recovered well with no neurological deficit. Retrospectively, he was able to recall the events and while he was lying paralysed and intubated under minimal sedation in the intensive care unit. He described it as a terrifying and painful experience. This case highlights the rare presentation of locked-in syndrome following a systemic envenoming from a king cobra bite. It is important to differentiate neurotoxic snake envenoming lock-in syndrome from brain dead. Patients are unable to respond to physical pain and require adequate analgesia. A patient suffering this highly distressing experience may require psychological support.

Clinical update on scorpion envenoming

Abstract: Scorpion stings are currently the leading cause of venom-related injury to humans in Brazil and are a significant public health problem globally. Only scorpions of the Tityus genus are of medical importance in Brazil, and Tityus serrulatus is responsible for the most serious envenomations and deaths. The toxic effects of scorpion envenomation are due to a massive release of sympathetic and parasympathetic neurotransmitters; the severity is related to cardiac and hemodynamic changes, with cardiogenic shock and pulmonary edema contributing to the main causes of death. The pathophysiology of cardiac involvement has been discussed for decades and has been attributed to adrenergic discharge and a possible toxic effect of venom on the myocardium, while acute pulmonary edema may have a cardiogenic and/or non-cardiogenic origin. Currently, the clinical data point to catecholamine excess as the cause for reversible scorpion cardiomyopathy . These data include electrocardiographic changes, profiling of cardiac enzymes and troponin I, echocardiographic data with global or regional left ventricle dysfunction, and myocardial perfusion alterations compatible with spasm in the coronary microcirculation. Furthermore, recent data on cardiac magnetic resonance imaging findings, which are similar to those observed for stress-induced cardiomyopathy, have also been linked to catecholamine excess. The efficiency of antivenom serum treatment is controversial in the literature. Our experience in Brazil is that the management of patients with systemic manifestations of scorpion stings is based on three approaches, all of which are extremely important. These include symptomatic treatment, antivenom serum, and cardiorespiratory support.

Indian common krait envenomation presenting as fulminant myocarditis and coma: a case report.

Fulminant myocarditis is an unusual manifestation of cardiotoxicity with severe elapid snake envenoming and is meagrely reported with snake bite due to Indian common krait. We report a 12-year-old boy who was admitted in complete locked-in state and hemodynamic instability after severe neurotoxic snake envenoming by Bungarus caeruleus (Indian common krait). His hospital course was complicated with recurrent episodes of sustained ventricular tachycardia requiring defibrillation; and cardiogenic shock requiring inotropes, vasopressors and intraaortic balloon counterpulsation. Severe heart failure features secondary to fulminant toxic myocarditis persisted even after full neurological recovery requiring prolonged standard medical heart failure therapy. Patient subsequently achieved full clinical recovery and regained normal left ventricular systolic function. We also reviewed the literature on cardiac manifestations, possible mechanisms and treatment of patients with cardiotoxicity due to elapid snake bites. The importance of anticipating severe cardiovascular complications is highlighted to help formulate appropriate therapeutic strategy.

Current challenges for confronting the public health problem of snakebite envenoming in Central America

Snakebite envenoming is a serious public health problem in Central America, where approximately 5,500 casesoccur every year. Panama has the highest incidence and El Salvador the lowest. The majority, and most severe,cases are inflicted by the pit viper Bothrops asper (family Viperidae), locally known as ‘terciopelo’, ‘barba amarilla’ or‘equis’. About 1% of the bites are caused by coral snakes of the genus Micrurus (family Elapidae). Despite significantand successful efforts in Central America regarding snakebite envenomings in the areas of research, antivenommanufacture and quality control, training of health professionals in the diagnosis and clinical management of bites,and prevention of snakebites, much remains to be done in order to further reduce the impact of this medicalcondition. This essay presents seven challenges for improving the confrontation of snakebite envenoming inCentral America. Overcoming these challenges demands a coordinated partnership of highly diverse stakeholdersthough inter-sectorial and inter-programmatic interventions.

Hump-nosed viper bite: an important but under-recognized cause of systemic envenoming

Hump-nosed viper bites are common in the Indian subcontinent. In the past, hump-nosed vipers (Hypnale species) were considered moderately venomous snakes whose bites result mainly in local envenoming. However, a variety of severe local effects, hemostatic dysfunction, microangiopathic hemolysis, kidney injury and death have been reported following envenoming byHypnale species. We systematically reviewed the medical literature on the epidemiology, toxin profile, diagnosis, and clinical, laboratory and postmortem features of hump-nosed viper envenoming, and highlight the need for development of an effective antivenom.

Clinical aspects of envenomation caused by Tityus obscurus (Gervais, 1843) in two distinct regions of Pará state, Brazilian Amazon basin: a prospective case series

Scorpion envenomations are a major public health problem in Brazil, whose most dangerous cases are attributable to the genus Tityus. This study was designed to compare the clinical and demographic features of envenomations by 77tyus obscurus in two areas of the state of Pará located in the Amazon basin. Were compared demographic findings, local and systemic signs and symptoms of human envenomations caused by T. obscurus that occurred in western and eastern areas of the state.

Current challenges for confronting the public health problem of snakebite envenoming in Central America

Snakebite envenoming is a serious public health problem in Central America, where approximately 5,500 casesoccur every year. Panama has the highest incidence and El Salvador the lowest. The majority, and most severe,cases are inflicted by the pit viper Bothrops asper (family Viperidae), locally known as ‘terciopelo’, ‘barba amarilla’ or‘equis’. About 1% of the bites are caused by coral snakes of the genus Micrurus (family Elapidae). Despite significantand successful efforts in Central America regarding snakebite envenomings in the areas of research, antivenommanufacture and quality control, training of health professionals in the diagnosis and clinical management of bites,and prevention of snakebites, much remains to be done in order to further reduce the impact of this medicalcondition. This essay presents seven challenges for improving the confrontation of snakebite envenoming inCentral America. Overcoming these challenges demands a coordinated partnership of highly diverse stakeholdersthough inter-sectorial and inter-programmatic interventions.