Scorpion envenomation among children: clinical manifestations and outcome (analysis of 685 cases)

A multiplexing immunosensing platform for the simultaneous detection of snake and scorpion venoms: Towards a better management of antidote administration

Envenomation accidents are usually diagnosed at the hospital through signs and symptoms assessment such as short breath, dizziness and vomiting, numbness, swilling, bruising, or bleeding around the affected site. However, this traditional method provides inaccurate diagnosis given the interface between snakebites and scorpion stings symptoms. Therefore, early determination of bites/stings source would help healthcare professionals select the suitable treatment for patients, thus improving envenomation management. In this study, we developed an innovative multiplexing platform based on dual immunosensors for the simultaneous determination of snake and scorpion venoms using a label-free electrochemical platform. The dual immunosensor was fabricated on graphene/gold nanoparticle modified screen-printed electrodes. The electrodes were first modified with two chemical linkers (cysteamine/phenylene diisothiocyanate) to facilitate the immobilization of the antibodies (antivenoms) through covalent binding. The proposed immunosensor was tested with different venoms that specific to six snake species and two scorpion species. The detection was undergone by monitoring the reduction peak current variation after the venom binding using square wave voltammetry, in presence of ferro/ferricyanide redox system. The dual immunosensor enabled a sensitive and selective simultaneous detection of the snake and scorpion species venoms within wide linear ranges in the limits of detection ranging from 0.057 to 0.027 μg/mL. The applicability of the venoms immunosensor has also been evaluated for the detection of snake and scorpion venoms in human serum samples showing high recovery percentages. These achievements show the great potential of our multiplexing approach for the early detection of snake or scorpion envenomation.

The aetiologies, mortality, and disability of non-traumatic coma in African children: a systematic review and meta-analysis

BACKGROUND

Non-traumatic coma in African children is a common life-threatening presentation often leading to hospital attendance. We aimed to estimate the distribution of non-traumatic coma causes and outcomes, including disease-specific outcomes, for which evidence is scarce.

METHODS

We systematically reviewed MEDLINE, Embase, and Scopus databases from inception to Feb 6, 2024. We included studies recruiting children (aged 1 month to 16 years) with non-traumatic coma (Blantyre Coma Scale score ≤2, ie deep coma or comparable alternative) from any African country. Disease-specific studies were included if outcomes were reported. Primary data were requested where required. We used a DerSimonian-Laird random effects model to calculate pooled estimates for prevalence of causes, mortality, and morbidity (in-hospital and post-discharge), including analysis of mortality by temporality. This study was registered with PROSPERO (CRD4202014193).

FINDINGS

We screened 16 666 articles. 138 studies were eligible for analysis, reporting causes, outcome data, or both from 35 027 children with non-traumatic coma in 30 African countries. 114 (89%) of 128 studies were determined to be high quality. Among the causes, cerebral malaria had highest pooled prevalence at 58% (95% CI 48-69), encephalopathy of unknown cause was associated with 23% (9-36) of cases, and acute bacterial meningitis was the cause of 10% (8-12) of cases, with all other causes representing lower proportions of cases. Pooled overall case-fatality rates were 17% (16-19) for cerebral malaria, 37% (20-55) for unknown encephalopathy, and 45% (34-55) for acute bacterial meningitis. By meta-regression, there was no significant difference in cerebral malaria (p=0·98), acute bacterial meningitis (p=0·99), or all-cause coma (p=0·081) mortality by year of study. There was no substantial difference in deaths associated with cerebral malaria in-hospital compared with post-discharge (17% [16-19] vs (18% [16-20]). Mortality was higher post-discharge than in-hospital in most non-malarial comas, including acute bacterial meningitis (39% [26-52]) vs 53% [38-69]). Disability associated with cerebral malaria was 11% (9-12). Pooled disability outcomes associated with other non-malarial diseases were largely absent.

INTERPRETATION

The prevalence and outcomes of cerebral malaria and meningitis associated with non-traumatic coma were strikingly static across five decades. Enhanced molecular and radiological diagnostics, investment, policy making, community awareness, and health service provision are all required to facilitate earlier referral to specialist centres, to drive a step-change in diagnostic yield and treatment options to improve these outcomes.

FUNDING

Wellcome Trust.

TRANSLATIONS

For the Chichewa, French and Portuguese translations of the abstract see Supplementary Materials section.

Myocardial Ischemia after Severe Scorpion Envenomation: A Narrative Review

Myocardial ischemia after severe scorpion envenomation is rarely reported. The aim of this review was to elaborate on a review of myocardial ischemia after severe scorpion envenomation and to detail the mechanism of this myocardial hypoperfusion. We used the PubMed database and entered the following keywords in MeSH research: scorpion envenomation, myocardial ischemia, myocardial perfusion scintigraphy, echocardiography, and troponins. The literature analysis confirmed that severe scorpion envenomation can be complicated by temporary myocardial ischemia, based on electrocardiographic, histopathologic, echocardiographic, myocardial perfusion scintigraphy, and biological studies. The correlation between clinical manifestations, laboratory and electrocardiographic evidence of myocardial damage, echocardiographic studies, perfusion scintigraphy abnormalities, and histopathologic findings are suggestive of lesions of cardiac fibers secondary to myocardial ischemia. Myocardial hypoperfusion may be due to multiple factors. First, catecholamine storms can induce microvascular constriction. On the other hand, the release of catecholamines through a complex neurohormonal interaction with other neuropeptides and cytokine release can produce/induce major coronary microvascular constriction and/or microvascular injury, leading to microvascular acute coronary syndrome with Takotsubo cardiomyopathy. The management of severe scorpion envenomation with severe myocardial failure and pulmonary edema is based on oxygen with invasive or noninvasive ventilator support. Dobutamine improves cardiac function after scorpion envenomation. Antiplatelet therapy is not recommended. In conclusion, severe scorpion envenomation can be complicated by temporary myocardial ischemia, which can be due to multiple factors.

Diagnosis of human envenoming by terrestrial venomous animals: Routine, advances, and perspectives

Despite the development of new and advanced diagnostic approaches, monitoring the clinical evolution of accidents caused by venomous animals is still a challenge for science. In this review, we present the state of the art of laboratory tests that are routinely used for the diagnosis and monitoring of envenomings by venomous animals, as well as the use of new tools for more accurate and specific diagnoses. While a comprehensive range of tools is outlined, comprising hematological, biochemical, immunoassays, and diagnostic imaging tools, it is important to acknowledge their limitations in predicting the onset of clinical complications, since they provide an overview of organic damage after its development. Thus, the need for discovery, validation, and use of biomarkers that have greater predictive power, sensitivity and specificity is evident. This will help in the diagnosis, monitoring, and treatment of patients envenomated by venomous animals, consequently reducing the global burden of morbidity and mortality.

The complex repertoire of Tityus spp. venoms: Advances on their composition and pharmacological potential of their toxins

Animal venoms are a rich and complex source of components, including peptides (such as neurotoxins, anionic peptides and hypotensins), lipids, proteins (such as proteases, hyaluronidases and phospholipases) and inorganic compounds, which affect all biological systems of the envenoming victim. Their action may result in a wide range of clinical manifestations, including tachy/bradycardia, hyper/hypotension, disorders in blood coagulation, pain, edema, inflammation, fever, muscle paralysis, coma and even death. Scorpions are one of the most studied venomous animals in the world and interesting bioactive molecules have been isolated and identified from their venoms over the years. Tityus spp. are among the scorpions with high number of accidents reported in the Americas, especially in Brazil. Their venoms have demonstrated interesting results in the search for novel agents with antimicrobial, anti-viral, anti-parasitic, hypotensive, immunomodulation, anti-insect, antitumor and/or antinociceptive activities. Furthermore, other recent activities still under investigation include drug delivery action, design of anti-epileptic drugs, investigation of sodium channel function, treatment of erectile disfunction and priapism, improvement of scorpion antivenom and chelating molecules activity. In this scenario, this paper focuses on reviewing advances on Tityus venom components mainly through the modern omics technologies as well as addressing potential therapeutic agents from their venoms and highlighting this abundant source of pharmacologically active molecules with biotechnological application.

Takotsubo cardiomyopathy following scorpion envenomation: a literature review

BACKGROUND

Takotsubo syndrome is comparable to microvascular acute coronary syndrome. It may partly share the same pathophysiology debated during scorpion envenomation (SE), with an adrenergic storm, without myocardial infarction due to the absence of coronary artery stenosis. Takotsubo cardiomyopathy can help to better understand the pathophysiology of cardiac involvement during scorpion envenomation. However, Takotsubo syndrome seems to be underestimated in the literature in patients suffering from cardiac failure following SE.

METHODS

In this review, we aimed to detail all described cases, the mechanism, and outcomes of scorpion envenomation complicated by Takotsubo cardiomyopathy. We used the PubMed database by using the following keywords in MeSH research: scorpion envenomation, Takotsubo cardiomyopathy, and Takotsubo syndrome.

RESULTS

The literature analysis showed the existence of only four cases of confirmed Takotsubo cardiomyopathy following severe SE. All four patients developed a transient reversible left ventricular systolic dysfunction in the absence of coronary artery disease, following a positive history of scorpion envenomation. A cardiac MRI was performed in all cases, showing a ballooning in the left ventricle associated with a left ventricular ejection fraction in all cases. All patients were improved under symptomatic treatment, and complete recovery of the wall motion was observed.

CONCLUSION

Takotsubo syndrome, although not often reported in the literature in severe SE, can represent an effective hypothesis explaining the pathophysiology of cardiac involvement during SE. In severe scorpion envenomation, multiple mechanisms exist and can explain the development of Takotsubo syndrome. Its management is based on oxygen, with invasive or non-invasive ventilator support in patients with respiratory failure and/or cardiogenic shock. Beta-blockers, mineralocorticoid receptor antagonists, and diuretics are usually used in Takotsubo syndrome. However, in severe scorpion envenomation, all reported cases of Takotsubo cardiomyopathy are associated with cardiogenic shock and acute pulmonary edema. As a consequence, we advise the use of Dobutamine since it has already been confirmed that cardiac dysfunction following scorpion envenomation improves well and safely under Dobutamine infusion.

A Hybrid Approach Based on Seasonal Autoregressive Integrated Moving Average and Neural Network Autoregressive Models to Predict Scorpion Sting Incidence in El Oued Province, Algeria, From 2005 to 2020

BACKGROUND

This study was designed to find the best statistical approach to scorpion sting predictions. Study Design: A retrospective study.

METHODS

Multiple regression, seasonal autoregressive integrated moving average (SARIMA), neural network autoregressive (NNAR), and hybrid SARIMA-NNAR models were developed to predict monthly scorpion sting cases in El Oued province. The root mean square error (RMSE), mean absolute error (MAE), and mean absolute percentage error (MAPE) were used to quantitatively compare different models.

RESULTS

In general, 96909 scorpion stings were recorded in El Oued province from 2005-2020. The incidence rate experienced a gradual decrease until 2012 and since then slight fluctuations have been noted. Scorpion stings occurred throughout the year with peaks in September followed by July and August and troughs in December and January. Sting cases were not evenly distributed across demographic groups; the most affected age group was 15-49 years, and males were more likely to be stung. Of the reported deaths, more than half were in children 15 and younger. Scorpion's activity was conditioned by climate factors, and temperature had the highest effect. The SARIMA(2,0,2)(1,1,1)12, NNAR(1,1,2)12, and SARIMA(2,0,2)(1,1,1)12-NNAR(1,1,2)12 were selected as the best-fitting models. The RMSE, MAE, and MAPE of the SARIMA and SARIMA-NNAR models were lower than those of the NNAR model in fitting and forecasting; however, the NNAR model could produce better predictive accuracy.

CONCLUSION

The NNAR model is preferred for short-term monthly scorpion sting predictions. An in-depth understanding of the epidemiologic triad of scorpionism and the development of predictive models ought to establish enlightened, informed, better-targeted, and more effective policies.

Spatiotemporal bayesian modelling of scorpionism and its risk factors in the state of São Paulo, Brazil

BACKGROUND

Scorpion stings in Brazil represent a major public health problem due to their incidence and their potential ability to lead to severe and often fatal clinical outcomes. A better understanding of scorpionism determinants is essential for a precise comprehension of accident dynamics and to guide public policy. Our study is the first to model the spatio-temporal variability of scorpionism across municipalities in São Paulo (SP) and to investigate its relationship with demographic, socioeconomic, environmental, and climatic variables.

METHODOLOGY

This ecological study analyzed secondary data on scorpion envenomation in SP from 2008 to 2021, using the Integrated Nested Laplace Approximation (INLA) to perform Bayesian inference for detection of areas and periods with the most suitable conditions for scorpionism.

PRINCIPAL FINDINGS

From the spring of 2008 to 2021, the relative risk (RR) increased eight times in SP, from 0.47 (95%CI 0.43-0.51) to 3.57 (95%CI 3.36-3.78), although there has been an apparent stabilization since 2019. The western, northern, and northwestern parts of SP showed higher risks; overall, there was a 13% decrease in scorpionism during winters. Among the covariates considered, an increase of one standard deviation in the Gini index, which captures income inequality, was associated with a 11% increase in scorpion envenomation. Maximum temperatures were also associated with scorpionism, with risks doubling for temperatures above 36°C. Relative humidity displayed a nonlinear association, with a 50% increase in risk for 30-32% humidity and reached a minimum of 0.63 RR for 75-76% humidity.

CONCLUSIONS

Higher temperatures, lower humidity, and social inequalities were associated with a higher risk of scorpionism in SP municipalities. By capturing local and temporal relationships across space and time, authorities can design more effective strategies that adhere to local and temporal considerations.

The Activity of Metalloproteases and Serine Proteases in Various Organs after Leiurus macroctenus Envenomation

Background

Scorpion stings may be life-threatening since their venoms are comprised of a wide range of toxins and other bioactive molecules, such as enzymes. At the same time, scorpion envenomation may increase matrix metalloproteases (MMPs) levels, which enhance proteolytic tissue destruction by venom. However, investigations on the impact of many scorpions' venoms, such as those of Leiurus macroctenus, on tissue proteolytic activity and MMP levels have not yet been conducted.

Methods and Results

The present study aimed to examine the total proteolysis levels in various organs after Leiurus macroctenus envenomation and evaluate the metalloproteases and serine proteases' contributions to the total proteolytic activity. Changes in MMPs and TIMP-1 levels were tested as well. Envenomation led to a significant increase in proteolytic activity levels in all assessed organs, mostly in the heart (by 3.34 times) and lungs (by 2.25 times).

Conclusions

Since EDTA presence showed a noticeable decrease in total proteolytic activity level, metalloproteases appeared to play a prominent role in total proteolytic activity. At the same time, MMPs and TIMP-1 levels were increased in all assessed organs, suggesting that Leiurus macroctenus envenomation causes systemic envenomation, which may induce multiple organ abnormalities, mostly because of the uncontrolled metalloprotease activity.

Scorpion envenomation in Brazil: Current scenario and perspectives for containing an increasing health problem

Opportunistic scorpion species can colonize urban environments, establishing high-density communities that enhance the chances of human accidents. This scenario has been taking place in Brazil, in which some Tityus species have taken city centers, causing an explosion in the number of scorpion envenoming cases. The characteristics of this scorpionism epidemic in Brazil is discussed in the present work. The number of Brazilian scorpion stings has surpassed 120,000 cases in 2017, and has been maintained above this number ever since, representing a more than 3-fold increase in 10 years, which was higher than the number of cases for most of the neglected tropical diseases in the country. The escalation in scorpionism cases is even higher in some regions of Brazil. Fortunately, the proportion of mild cases has also increased in the analyzed period, as well as the number of victims seeking for medical attention within the first hour after the accident. The species Tityus serrulatus, Tityus stigmurus, Tityus bahiensis, and Tityus obscurus are traditionally accountable for most of the scorpion accidents in different regions of Brazil, but other species deserve to be closely watched. Despite scorpionism being a notable health problem in Brazil, accident prevention and pest control regarding this venomous animal have not been properly addressed by the scientific community nor by policy makers. Therefore, this review also aims to point possible fields of research that could help to contain the aggravation of the current scorpionism landscape in Brazil.

Detection of areas vulnerable to scorpionism and its association with environmental factors in São Paulo, Brazil

Accidents caused by scorpions are considered a neglected condition and represent a major health problem in most tropical countries, especially for children and elderly people. In Brazil, scorpionism is recurrent in the southeast region, mainly in the state of São Paulo, due to the progressive increase in scorpions found in urban habitats. Thus, our study aimed to provide better insights into the geographic and epidemiological characteristics of scorpion envenomation in São Paulo state and identify the environmental factors that are associated with these accidents. This is an ecological and retrospective study with secondary data on scorpion accidents in the state of São Paulo from 2008 to 2018 obtained from the Notifiable Disease Information System. The SatScan software was used to identify the higher- and lower-risk spatiotemporal clusters. A total of 145,464 scorpion sting cases were recorded in the state of São Paulo, between 2008 and 2018; there was a four-fold increase in the incidence rate. Accidents occurred more frequently in the spring season, wherein higher-risk clusters were in the north and northwest regions of the state. High temperatures, low precipitation, and poor natural vegetation are associated with higher risk areas. Our study mapped vulnerable areas for scorpion accidents that can aid in the design of efficient public health policies, which should be intensified during the spring season.

Scorpion envenomation in the state of São Paulo, Brazil: Spatiotemporal analysis of a growing public health concern

Scorpion envenomation is a significant public health concern in São Paulo, Brazil, and its incidence and mortality have increased in recent decades. The present study analyzed documented scorpion envenomation notifications from 2008 to 2018 throughout the 645 municipalities of São Paulo. Annual incidence and mortality rates were calculated and stratified according to sex and age. The local empirical Bayesian method and Getis-Ord Gi* statistic were used to represent standardized incidence rates in the municipalities and to identify high- and low-risk agglomerates. The incidence rate of scorpion envenomation quintupled between 2008 and 2018. Overall, the risk was higher for man, and increased with age. Deaths due to envenomation, however, were concentrated almost entirely in children 0–9 years of age. Incidence maps showed that the risk of envenomation increased in almost all regions and municipalities of São Paulo throughout the study period. The highest incidence rates were found in the western, northwestern and northern regions of the state, in contrast to the São Paulo metropolitan area and southern and coastal regions. Hot spots were identified in the Presidente Prudente, Barretos, São José do Rio Preto, and Araçatuba regional health districts, which over time formed a single high-risk cluster. In spatial terms, however, deaths were randomly distributed. In this study, we identified areas and populations at risk of scorpion envenomation and associated–fatalities, which can be used to support decision-making by health services to reduce human contact with these arachnids and avoid fatalities, especially in children.

Predictive Value of Glycemia and Free Fatty Acid Levels upon Admission of Children with Scorpionism in Egypt

Scorpion envenomation is a life-threatening emergency and causes serious health problems in tropical and subtropical regions. The aim of this study was to correlate the serum levels of biochemical parameters at admission in children with scorpion envenomation with subsequent morbidity and mortality. It was a prospective, observational, and descriptive study conducted for scorpion-envenomed children who presented to emergency and intensive care units between April 2019 and September 2019. Demographic, clinical, and laboratory findings of patients were recorded and tabulated. Routine investigations were done for all patients in addition to blood levels of lactate, free fatty acids (FFA), and insulin. All patients were compared according to outcome as survivors and nonsurvivors and according to glucose level as normoglycemic and hyperglycemic groups. There were 62 scorpion sting cases; their mean age was 8.6 ± 3.2 years. Patients aged more than 6 years (74.2%), and males (66.1%) were more affected than others. As regards severity, 25.8% were suffering organ dysfunction, 40.3% suffered systemic manifestations without organ dysfunction, and (33.9%) with only local manifestations. Serum glucose and FFA were significantly higher in nonsurvivors compared with survivors. Shock, convulsion, coma, heart failure, and pulmonary edema were significantly more common in hyperglycemic than normoglycemic group. Hyperglycemia, and raised FFA were associated with severe scorpion envenomation. Raised FFA was well correlated with presence of heart failure, leucocytosis, and hyperglycemia. Adding serum glucose and FFA to monitoring parameters of scorpionism severity can help the prediction of high-risk patients.

Clinical features and prognosis of severe scorpion envenomation in children

BACKGROUND

Scorpionism is endemic and represents a real public health problem in Morocco. The most dangerous arthropod in the central area is Androctonus mauretanicus (Am) scorpion. Its venom can be lethal, especially for children. This study aimed to determine a clinico-epidemiological profile of severe scorpion envenomation among children and identify risk factors for mortality.

METHODS

This retrospective cohort study included 606 children admitted for severe scorpion envenomation (SSE) from January 2010 to July 2015 in the Pediatric Intensive Care Unit (PICU) of Mohammed VI Teaching Hospital.

RESULTS

The mean age of envenomed children was 6.3 ± 4.2 years. Seventy-four percent of them came from rural settings. Envenomation occurred mostly during the summer months and 78.4% of stings were nocturnal. The time between the sting and evaluation was greater than 2 h in 83% of cases. Bivariate analysis indicated that from 1 to 24 months of age (P = 0.001), hyperthermia (P = 0.022), episodes of diarrhea (P < 0.001), tachycardia (P < 0.001), abdominal distention (P < 0.001), skin marbling (P < 0.001), signs of respiratory distress (P < 0.001), irritability (P < 0.001), generalized seizures (P = 0.053), and Glasgow Coma Score (GCS) of 3 to 9 (P < 0.001) were significantly correlated with mortality. On multivariate analysis, diarrhea (P = 0.007), skin marbling (P = 0.006), and respiratory distress (P = 0.002), and GCS 3-9 (P = 0.007) were found to be independent risk factors for mortality in our patient population.

CONCLUSIONS

Children are at high risk of developing serious complications, even death, from severe scorpion envenomation. Here we identified multiple factors that appear to increase the mortality risk in children after scorpion envenomation, including previously described central nervous system alterations.

Echocardiographic Evaluation of the Response to Prazosin Treatment in Scorpion Sting

BACKGROUND

Scorpion envenomation is a major public health problem in children that can induce lethal neurological, respiratory and cardiovascular complications. We aimed to evaluate cardiovascular complications with a follow-up of envenomed children for 1 month for possibility of incomplete recovery.

METHODS

This was a prospective study conducted for children who presented with scorpion sting to Emergency and Intensive Care units. Demographic, clinical and laboratory findings of patients were recorded. Cases with suspected clinical and electrocardiographic manifestations of myocarditis were subjected to bedside echocardiography with follow-up at the end of the first week and the first month.

RESULTS

Scorpion sting cases presented to our hospital were 81 cases during 1-year study; of them, 17 cases were stable without systemic manifestations after 12 h observation and discharged. Sixty-four cases suffered systemic organic complications and needed ICU admission; their mean age was 11.52 ± 3.74 and 64% of them were males. Twenty-eight of admitted cases showed manifestations of myocarditis and by echocardiography, all of them had evidence of left ventricular dysfunction. On follow-up, there was significant improvement at the end of first week and complete improvement at the end of first month except three cases who died due to pulmonary edema and cardiogenic shock.

CONCLUSION

Acute toxic myocarditis is a common and an important cause of morbidity and mortality following scorpion envenomation that necessitates early and aggressive management. High index of suspicion, serial electrocardiogram monitoring and echocardiography are three integrative lines required to recognize this serious complication. Lay summaryAcute toxic myocarditis is a common cause of morbidity and mortality following scorpion envenomation that necessitates rapid medical treatment. We aimed to evaluate cardiovascular complications after scorpion sting with a follow-up of envenomed children for 1 month for possibility of incomplete recovery. Tachycardia was the most frequent observed cardiac sign followed by hypotension, while the least was bradycardia and hypertension. All cases with manifestations suggestive of myocarditis were evaluated by bedside two-dimensional echocardiography and showed evidence of left ventricular dysfunction, that begin to regress within 1 week of treatment unless progressive pulmonary edema and resistant cardiogenic shock occurred. On follow-up for survivors, complete improvement at the end of first month was noticed. Clinical suspicion, serial ECG monitoring and echocardiography are required for rapid and early diagnosis. Early use of prazosin therapy can prevent long-term residual damage as evidenced by echocardiographic evaluation.

Clinical Effects and Predictive Factors Affecting the Clinical Severity of Scorpion Envenomations in Western Turkey

BACKGROUND

Scorpion envenomation is a common medical emergency in many countries, including Turkey. Severe systemic symptoms occur more easily in children and mortality rates are higher. The aim of this study is to describe the clinical effects and predictive factors affecting the clinical severity of scorpion envenomations in Western Turkey.

METHODS

Two hundred one children (138 mild cases, 34 moderate, and 29 severe) with scorpion envenomation aged between 1 month and -17 years were included in the study. The patients' demographic and laboratory characteristics were compared among clinical severity subgroups.

RESULTS

The patients' median age was 7 (4-11) years. The median age of the severe group was significantly lower than that of the mild and moderate groups (p < 0.001). Seventeen patients (8.5%) developed myocarditis, while no pulmonary edema was observed in any case. Leukocyte, neutrophil and platelet (PLT) counts, and plateletcrit (PCT) and glucose levels increased significantly with the severity of envenomation (p < 0.001). PLT counts and PCT levels exhibited positive correlation with leukocyte and neutrophil counts (p < 0.001, r = 0.781, r = 0.638, r = 0.772, and r = 0.629, respectively). Supraventricular tachycardia developed in 1 (5.9%) patient, and dilated cardiomyopathy in another (5.9%). No mortality occurred in any case.

CONCLUSION

Increased PLT counts and PCT levels may be helpful in evaluating clinical severity in patients with scorpion sting envenomation. The possibility of myocarditis development in children should be remembered and cardiac enzymes should be checked, even if patients are asymptomatic and cardiac enzymes are normal on admission.

Effects of climate variables on the incidence of scorpion stings in Iran for five years

Background:

Although scorpionism is recorded worldwide, some regions such as Iran present a higher incidence. Due to the great prevalence of scorpion stings in Khuzestan province, southwestern Iran, the present study examined the relationship between different climate parameters and the scorpion sting rate in this area from April 2010 to March 2015.

Methods:

In this cross-sectional descriptive-analytical study, we considered all scorpion sting cases recorded in the Department of Infectious Diseases, Ahvaz Jundishapur University of Medical Sciences. Data were analyzed using statistics, frequency distribution and Pearson’s correlation coefficient.

Results:

A total of 104,197 cases of scorpion stings was recorded from 2010 to 2015. The cumulative incidence of scorpion sting was 2.23%. The spatial distribution of scorpion stings showed that most cases occurred in the Dehdez district (4,504 scorpion stings/100,000 inhabitants) and the Masjed Soleyman county (4,069 scorpion stings/100,000 inhabitants). A significant association was found between climate factors (temperature, evaporation rate, sunshine duration, humidity, and precipitation) and the scorpion sting rate. An increase in rainfall and humidity coincided with a reduction in scorpion stings whereas an increase in temperature, evaporation, and sunshine duration was accompanied by a growth of scorpion stings. No significant correlation was found between wind velocity/direction and the incidence rate of stings. Moreover, the seasonal peak incidence of scorpion stings was recorded in summer (an average of 8,838 cases) and the lowest incidence was recorded during winter (an average of 1,286 cases). The annual trend of scorpion sting cases decreased during the period from 2010 to 2015.

Conclusion:

Climate variables can be a good index for predicting the incidence of scorpion stings in endemic regions. Since they occur mostly in the hot season, designing preventive measures in the counties and districts with a high incidence of scorpion stings such as Dehdez and Masjed Soleyman can minimize mortality and other burdens.

Neurological and Systemic Manifestations of Severe Scorpion Envenomation

Scorpion envenomation is a life-threatening toxicological emergency and considered as a major public health problem, especially in endemic regions (India, Africa, Latin America); it is generally characterized by low resources and tropical or subtropical weather. Scorpion envenomation is especially fatal in the first hours, usually due to respiratory and/or cardiovascular collapse. The neurologic manifestations, triggered by multiple neurotoxic mechanisms, are varied and complex and mostly reported in children. The aim of this review is to clarify the epidemiologic characteristics and clinical manifestations as well as diagnosis and management of neurologic complications following scorpion envenomation. The management of patients with severe clinical forms is based on early recognition of the sting, antivenom serum administration, and cardiorespiratory and systemic support.

[Inverted Takotsubo Syndrome due to Severe Scorpion Envenomation: Report of one Case]

Scorpion envenomation (SE) is common in tropical and subtropical regions. Cardio-respiratory manifestations, mainly cardiogenic shock and pulmonary oedema are the leading causes of death after scorpion envenomation. Cardiac failure can be due to massive release of catecholamines, myocardial damage induced by the venom or myocardial ischemia. Although it has been exceptionally reported, Takotsubo syndrome during SE can help to better elucidate the pathophysiology of this cardiomyopathy. We report a case of inverted Takotsubo following a SE in a 26-year-old patient admitted to the Intensive care unit department for severe scorpion envenomation. His evolution was favorable. We concluded that cardiac involvement in this case fulfills all clinical and paraclinical criteria of Takotsubo syndrome emphasizing the importance of catecholaminergic discharge during scorpion envenomation. We discuss again the management of this syndrome in this specific condition.

Factors involved in the resilience of incidence and decrease of mortality from scorpion stings in Mexico

In Mexico, scorpion sting envenomation (SSE) is a significant public health issue that has engaged the attention of health authorities for more than a century. Rigorously characterized today, scorpion sting incidence is stable around 230 stings per 100,000 population, i.e. 300,000 annual stings treated in Mexican health centers and hospitals. Higher incidence is observed mainly in central and Pacific Mexico. Scorpion populations thrive in populated places, particularly in impoverished areas. Scorpion stings occur in houses. This could explain similar incidence according to gender and age. The number of scorpion stings has remained stable since the mid-2000s. In contrast, mortality, which was over 1500 deaths per year before the 1960s, underwent a dramatic drop after the 1970s, from 500 deaths per year to fewer than 50 annual deaths today. Case fatality rates have shown similar trend. We noted a significantly higher specific mortality in males than in females (0.199 and 0.168 per 100,000 respectively; P < 1.9·10^-6). Three causes explained the drop in mortality and case fatality rate, a) ongoing improvement in hospital care, particularly in terms of supportive standardized treatments, b) the use of highly purified immunoglobulin F(ab')₂ fragments after 1995 and, c) increasing access to health services for most of the Mexican population. The authors retrace the history of the management of SSE, including the development of antivenoms, in Mexico between 1905 and today.

Autopsy Findings in Case of Fatal Scorpion Sting: A Systematic Review of the Literature

Scorpion sting is a public health issue in several countries, particularly in America, the Middle East, India and Africa. The estimated annual global incidence of scorpion envenomings is about 1.5 million, resulting in 2600 deaths. Scorpions are Arthropoda characterized by a tail ending in a terminal bulbous (telson) containing paired venom glands and the stinger. There are 19 known families of scorpions and more than 2200 species, of which about 50 from the families of Buthidae, Hemiscorpiidae and Scorpionidae are harmful to humans. Scorpion venom is a complex structure composed of neurotoxic proteins, salts, acidic proteins and organic compounds, thereby having neurologic, cardiovascular, hematologic and renal side effects, in addition to local effects such as redness, pain, burning and swelling. When the sting is fatal, the mechanism of death is often related to cardiotoxicity with terminal pulmonary edema. However, the cholinergic excess or the neuromuscular excitation can provoke respiratory failure. Sometimes, death is due to an anaphylactic reaction to the envenoming. The purpose of this literature review is to evaluate the autopsy findings in scorpion sting-related deaths in order to better understand the pathophysiological mechanisms underlying them, thus helping pathologists in defining the correct diagnosis.

Tityus stigmurus venom causes genetic damage in blood and testicular cells and affects the number and morphology of gametogenic lineage cells in mice

Scorpion envenomation represents an important health problem in many parts of the world, due to the high number and severity of accidents. Recent studies demonstrated that some species can produce venoms with genetic damage potential. Here, we evaluated whether Tityus stigmurus venom causes genetic damage in blood and testicular cells of Swiss mice. We also analyzed the effect of the venom on the number of spermatogenic lineage cells. Five groups of mice received 0.387 mg/kg of the venom, intraperitoneally; one group received saline solution (control group). Blood and testicular cells were collected for comet assay and histological analysis at different times after treatment (1, 2, 6, 12, and 48 h). Blood was also collected 48 h after treatment for the micronucleus test in erythrocytes. Histological analysis was performed by counting cells of the spermatogenic lineages; the nuclear area of elongated spermatocytes was also evaluated. Treatment with the venom induced DNA damage that endured from 1 h to 48 h, as confirmed by the comet assay. The micronucleus test demonstrated that the venom induced mutations in erythrocytes. The number of spermatogonia and rounded spermatids decreased in some groups; the number of elongated spermatids increased, and their nuclear size decreased 1 h after treatment. Genetic damage can be caused directly by the venom, but we suggested that reactive oxygen species that result from inflammatory process caused by the envenomation may have an important role in the DNA damage. Genetic damage and apoptosis may explain the changes in the number of spermatogenic cells. Furthermore, the decrease in nuclear area may result from chromatin loss. Genetic damage in testicular cells, associated with alterations in the number and morphology of spermatogenic cells, can result in reproduction disorders in animals, or humans, stung by T. stigmurus.

A Relationship Between Clinical and Laboratory Characteristics in Children With Severe Scorpion Envenomation in Çukurova, Turkey

OBJECTIVE

Scorpion stings are an important health problem in many parts of the world. The aim of this study was to retrospectively examine cases of scorpion stings to evaluate their epidemiological, clinical, and laboratory features and to determine strategies that can reduce morbidity and mortality in these cases.

METHODS

Scorpion stings experienced by children between 2007 and 2013 were retrospectively reviewed. The patients were categorized into groups based on severities of toxicities, and demographic, clinical, and laboratory features were compared between the groups.

RESULTS

The mean ± SD age of the 189 patients with scorpion stings was 83.43 ± 59.62 months. There was a significant difference between the clinical stages and the age distribution of the cases (P < 0.05). White blood cell counts differed significantly between the groups (P < 0.05). There was not a significant difference in mean platelet volume and platelet distribution width between the groups, but plateletcrit and low platelet count were significantly different between stage 1 and stage 3 cases (P < 0.05). Glucose, creatinine kinase-myoglobin binding, and troponin I were also significantly different (P < 0.05). The mortality rate was 0%.

CONCLUSIONS

People living in regions where scorpion stings are frequent should be informed about preventive measures against these stings, cases of scorpion stings should be monitored in appropriate centers, and staff offering care to these cases should be educated about treatment methods. In addition, treatment protocols should be determined in accordance with regions where the stings occur and studies should be performed to describe prognostic indicators.

Retrospective clinical and epidemiological analysis of scorpionism at a referral hospital for the treatment of accidents by venomous animals in Alagoas State, Northeast Brazil, 2007-2017

Scorpionism has a high incidence rate in Brazil. It is considered a serious public health problem mainly in tropical and subtropical regions around the world. The number of scorpion accidents have increased over the years and the highest frequencies have been reported mainly in the Brazilian Northeast region. Therefore, in this study we report a retrospective clinical and epidemiological analysis of scorpion stings from 2007 to 2017 in Alagoas State, Northeast Brazil, at a referral hospital for assistance and treatment of accidents by venomous animals. During the analyzed period, the referral hospital treated 27,988 cases, and an increase in the number of cases has taken place over the years. The highest frequency of scorpion stings was observed in females, and the age range most affected was from 20 to 29 years old. The most stung body site was the foot, followed by finger, toe or hand. Regarding the severity, most severe cases were reported in children up to 4 years old (69.4%) and 50% of the total cases treated with serotherapy corresponded to patients in this age range. Interestingly, it was also found that the occurrence of systemic manifestations and the severity of the cases were significantly associated with pediatric patients. In this way, this study highlights the scorpionism as an environmental public health problem in Alagoas State, Northeast Brazil, as well as the need to intensify the epidemiological surveillance and educational campaigns to prevent and control scorpion accidents throughout the year.

Epidemiology of the injury with venomous animals in the state of Rio Grande do Norte, Northeast of Brazil

Abstract This report is an investigation of the epidemiological features of injuries with venomous animals in the Rio Grande do Norte state, Northeastern Brazil, from 2007 to 2014. A total of 30,429 cases were analyzed. Cases were distributed over all months of the period studied and occurred mainly in urban areas. Scorpion stings showed the highest percentage of cases, but the chance of death among snakebites was higher. Envenomation predominated in females with age between 20 and 49 years old. Children and elderly showed a higher chance of death. Most victims were bitten on the extremities of the limbs and received medical care within 0-1 hour after being bitten. The main local and systemic symptoms reported were pain and headache, respectively. Cases were mostly classified as mild and progressed to cure. Few victims show local and systemic complications. The high number of accidents with venomous animals shows that Rio Grande do Norte may be an important risk area for such injuries. Furthermore, this study provides data for the development of health actions to promote control and prevention of these injuries in this region.

Scorpion stings in pregnancy: an analysis of outcomes in 66 envenomed pregnant patients in Iran

Background:

Scorpionism is one of the most important health problems in tropical regions, which unfortunately results in thousands of deaths annually. Pregnant women are potential victims in areas with high scorpion-sting prevalence. Limited medical data are available on the effects of scorpion envenomation in pregnant women. This study aimed to examine the effect of scorpion envenomation on pregnancy outcomes in 66 cases.

Methods:

The present descriptive/analytical cross-sectional study was performed on 66 scorpion-envenomed pregnant women referred to the clinical toxicology unit of Ahvaz Razi Hospital in Iran during 2015-2017. The variables assessed in all cases, via questionnaire and hospital medical records, were: age, patient residency, gestational week, status of the fetus, laboratory anomalies, clinical severity of envenomation, sting site and scorpion species. Pregnancy outcome (miscarriage, stillbirth, preterm birth, normal delivery) and status of the newborns were also evaluated. Data were analyzed using SPSS ^® software (version 24.0).

Results:

The following pregnancy outcomes were recorded from envenomed pregnant women: miscarriage = 1.5% (n = 1), stillbirth = 4.5% (n = 3), preterm birth = 10.6% (n = 7), normal birth = 83% (n = 55). Among participants whose pregnancy led to birth, 11(17.7%) cases had prenatal-neonatal complications. Neonatal complications, including Apgar score less than 8 points at 5 min, were found in 7 (11.3%) preterm birth cases and in 4 (6.4%) normal birth cases, along with birth weight below 2500 g in normal births. A significant relationship was found between adverse pregnancy outcomes and bite location, as well as scorpion species, but no relationship was found with other variables.

Conclusion:

Envenomation significantly contributes to preterm birth. Moreover, the location of bites and the type of scorpion species have a decisive role in the pregnancy outcome of scorpion-envenomed pregnant women.

Predictors for Mortality in Children with Scorpion Envenomation Admitted to Pediatric Intensive Care Unit, Qena Governorate, Egypt

This study aimed to identify the clinical and laboratory manifestations that affect outcome of scorpion envenomation in children. It included 154 children admitted with scorpion sting envenomation over a period of 2 years. The epidemiological, clinical, and laboratory findings of patients were recorded, and grading of severity was performed based on local and systemic involvement. Organ failure was determined according to diagnostic criterion of multiple organ dysfunction syndrome, and severity of illness was assessed by the Pediatric Risk of Mortality (PRISM III) score. Of studied children, 58.4% were males and 41.6% were females. Children aged > 5 years suffered more scorpion stings (79.9%) than others did. The place of residence was rural more than urban, outdoor stings more than indoors, nocturnal more than diurnal, and most stings were on the exposed areas of the limbs. Based on clinical evaluation, 37.7% of patients were classified as class I severity followed by class II (48.7%) and class III (13.6%). Among studied cases, 21 deaths (13.6%) were registered; all of them belonged to class III severity. Mortality was significantly higher in children with agitation, coma, convulsions, arrhythmia, heart failure, pulmonary edema, and priapism. There were significantly higher values of leukocytes, platelets, creatinine, liver enzymes, glucose, and creatine phosphokinase in non-survivors than in survivors. The presence of organ failure was associated with mortality. In addition, the need for mechanical ventilation and inotropic support were at increased risk of mortality. Moreover, a significant association was found between PRISM score and the number of failed organs with fatal outcome.

Tb1, a Neurotoxin from Tityus bahiensis Scorpion Venom, Induces Epileptic Seizures by Increasing Glutamate Release

Here, we report the neurotoxic effects aroused by the intracerebral injection (in rats) of Tb1, which is a neurotoxin isolated from Tityus bahiensis scorpion venom. Biochemical analyses have demonstrated that this toxin is similar to the gamma toxin from T. serrulatus, which is a β-scorpion toxin that acts on sodium channels, causing the activation process to occur at more hyperpolarized membrane voltages. Male Wistar rats were stereotaxically implanted with intrahippocampal electrodes and cannulas for electroencephalographic recording and the evaluation of amino acid neurotransmitters levels. Treated animals displayed behavioral and electroencephalographic alterations similar to epileptiform activities, such as myoclonus, wet dog shakes, convulsion, strong discharges, neuronal loss, and increased intracerebral levels of glutamate. Scorpion toxins are important pharmacological tools that are widely employed in ion channel dysregulation studies. The current work contributes to the understanding of channelopathies, particularly epilepsy, which may originate, among other events, from dysfunctional sodium channels, which are the main target of the Tb1 toxin.

A retrospective study of scorpionism in 11 domestic dogs and a cat in the urban area of Manizales, Colombia

The present study analyzes cases of scorpionism in 11 dogs and a cat that were registered at a veterinary clinic in the city of Manizales, between 2009 and 2018. All eight cases where expert identification of the arthropod was possible, involved Centruroides gracilis (Latreille, 1804). None of the stings were lethal, though two cases were classified as severe envenomation and five moderate. The primary sign was local pain, in addition to lameness in all 10 cases that involved one of the limbs (83,3%, 10 of 12 cases). The other two cases had injuries involving the face. The established treatment was symptomatic with clinical and patient monitoring. Antivenom could not be used due to its high cost and scarcity. However, even the severest cases improved satisfactorily, and all patients were discharged without complication.

[Epidemiology of home accidents in childhood: experience in the Division of General Pediatrics in Southern Tunisia]

Les accidents domestiques représentent un problème sérieux de santé publique en pédiatrie. Ils sont responsables d’une lourde morbidité et mortalité parmi la population pédiatrique. Nous avons mené une étude rétrospective colligeant 231 cas d’accidents domestiques chez l’enfant au Service de Pédiatrie de l’Hôpital Hédi Chaker de Sfax durant une période de 5 ans (2008 - 2012). Durant la période d’étude, nous avons colligé 231 cas d’accidents domestiques. Il s’agissait de 124 garçons (53,7%) et 107 filles (46,3%). L’âge moyen était de 2 ans avec des extrêmes de 1 jour et 14 ans. Les enfants âgés de moins de 4 ans étaient les plus exposés (88,7%). Les intoxications accidentelles étaient les accidents les plus fréquents (105 cas). Les caustiques étaient les agents toxiques les plus fréquents (33 cas), suivis par les médicaments (28 cas) puis les hydrocarbures (16 cas). Les accidents par corps étrangers ont représenté le deuxième mécanisme accidentel (64 cas). Il s’agissait de 43 cas d’inhalation de corps étrangers et 21 cas d’ingestion de corps étranger. Nous avons enregistré 28 cas de traumatismes; il s’agissait d’une chute d’une certaine hauteur dans 25 cas. Nous avons recensé 26 cas d’envenimations scorpioniques, 5 noyades, 2 cas de brulure et un seul cas d’électrisation. Les intoxications accidentelles et les accidents par corps étrangers représentent les principaux accidents domestiques dans notre série et la tranche d’âge entre 1 et 4 ans est la plus exposée aux accidents domestiques.

Clinical and epidemiological aspects of scorpionism in the interior of the state of Bahia, Brazil: retrospective epidemiological study

BACKGROUND

Scorpion accidents have gained great visibility around the world because of the high frequency and severity with which they occur, and have become a global medical-sanitary problem.

OBJECTIVE

The aim of this study was to describe the sociodemographic, clinical and epidemiological profile of scorpionism in the municipality of Jequié, Bahia, Brazil, from 2007 to 2015.

DESIGN AND SETTING

Retrospective epidemiological study in the municipality of Jequié, Bahia, Brazil.

METHODS

This study was based on data collected from the epidemiological investigation notification forms of the injury information system.

RESULTS

There was an increase in the coefficient of incidence of scorpion accidents in Jequié from 23.4/100,000 in 2007 to 413.6/100,000 in 2015. There were 3565 cases: 54.9% were female, 58.8% were aged 20-59 years, 63.5% had brown skin color and 48.6% had incomplete primary education. Most accidents occurred in urban areas (93.1%). Homes were the main place of occurrence (84.5%) and upper limbs were the commonest sting sites (53.0%). Regarding clinical aspects, 66.4% of the cases received hospital assistance within one hour after the bite, 84.1% presented mild severity, 97.1% had local manifestations and 10.2% had systemic symptoms. Serum therapy was administered in 17.3% of the cases, and 99.9% evolved to cure.

CONCLUSION

There was an increase in the incidence of scorpion accidents in the municipality, which demonstrates the need for investment in actions that reduce the morbidity and mortality caused by these accidents, such as educational campaigns and improvements in socioeconomic and health conditions.

Levosimendan treatment in a child with treatment-resistant left ventricular systolic dysfunction after scorpion sting

Background:

Scorpion stings are common in countries dominated by rural and coastal settlements with temperate climate. Scorpion stings are usually harmless and can be seen in local findings, but in some cases, systemic, neurotoxic, and cardiotoxic findings can be seen.

Case report:

A 3 year 7 month old girl was referred to pediatric emergency care 2 h after yellow scorpion (species of Leiurus abdullahbayrami) sting. In our case, cardiac function insufficiently progressed in spite of the standard inotropic and milrinone treatment. On the third day of hospitalization, levosimendan was initiated with good clinical effect.

Conclusion:

In the literature, the use of levosimendan in pediatric patients has been limited to those with low cardiac output syndrome after cardiovascular surgery. The use of levosimendan in children with scorpion sting has been previously reported only in Banille et al.’s study. Scorpion antivenom should be administered intravenously as soon as possible in cases of systemic findings that develop after scorpion stings. This report suggests that levosimendan is temporally associated with improvement in patients who have severe cardiac dysfunction due to scorpion sting and refractory to current treatment.

FACTORS ASSOCIATED WITH THE SEVERITY OF SCORPIO POISONING

ABSTRACT Objective: to analyze the factors associated with the severity of scorpionism, according to sociodemographic, clinical and epidemiological aspects. Method: a cross-sectional study was carried out, in 2017, with data extracted directly from the Epidemiological Investigation Records of the Information System for Notifiable Diseases, for the period from 2007 to 2015. These records were provided by the reference hospital in attendance to the cases of scorpionism, located in the municipality of Jequié (Brazil). Logistic regression was used to verify the factors associated with the severity of scorpionism. Results: in the period investigated, 3,565 cases of scorpionism were identified, of which 15.9% were classified as of greater severity. The adjusted analysis showed that the severity of the scorpionism is associated with the ages ranging from 0 to 9 years (OR=6.87; CI 5.23-9.03), from 10 to 19 years old (OR=1.39; CI 1.03-1.87) and 60 or more (OR=4.04, CI 3.12-5.23), and the time elapsed between the moment of the bite and the hospital care of more than 3 hours (OR = 1.38; CI 1.02-1.85). Conclusion: it was found that the age range and the time elapsed between the moment of the bite and the hospital care are associated with the severity of the scorpionism, which signals the emergency characteristics of these accidents, especially when children and elderly people are affected.

Evidence of Direct Toxicological Effects of Scorpion Venom on Central Nervous System in Tunisian Children

Background

Severe scorpion envenomation can lead to severe neurological manifestations, which are an indicator of the severity of the scorpion sting. The direct action of scorpion venom on the central nervous system can explain partly these neurological disorders.

Methods and Findings

We report a case of severe scorpion envenomation in 16-month-old boy with no pathological history admitted in ICU for severe scorpion envenomation. The result of cerebral MRI agrees with the hypothesis of direct action of scorpion venom on the central nervous system. Patient had improved; however, he has kept as neurological sequelae language disorders and blindness. The boy was discharged 21 days after ICU admission.

Conclusion

Our observation confirms that severe scorpion envenomation can be complicated by severe neurological manifestations. Although one case report is not enough to conclude such important hypothesis regarding the direct effect of scorpion venom on central nervous system (especially that the age of patient is more than one year), our case agrees with this hypothesis.

Myocardial injury induced by scorpion sting envenoming and evidence of oxidative stress in Egyptian children

In the present study, 45 children in Upper Egypt (less than 16 years old) were admitted to the Pediatric Intensive Care Unit for scorpion envenomation (SE). They were compared with 30 apparently healthy children of matching age and sex as controls. Out of the studied victims, 35 children (78%) showed signs of severe envenomation, while 10 victims (22%) showed signs of mild envenomation. The case fatality was 33%. The serum levels of cardiac markers, cardiac troponin T (cTnT) and I (cTnI), as well as the enzymatic activities of creatine kinase-MB (CPK-MB) and lactate dehydrogenase (LDH) were determined for both victims and controls. In addition, the serum levels of oxidative stress markers, nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD), reduced glutathione (GSH) and zinc (Zn) were measured. Electrocardiography and echocardiography were done. All the envenomed victims showed significantly higher mean values of cTnT, cTnI, CPK-MB and LDH than control group. These cardiac markers were elevated in severe cases and in non survivors in comparison with mild cases and survivors respectively. Furthermore, the serum levels of NO and MDA were significantly higher while the serum levels of SOD, GSH and Zn were significantly lower in all envenomed victims than the controls (p < 0.05 for all). There were no significant differences in the serum levels of oxidative stress markers among severe and mild cases or between survivors and non survivors victims. There were no significant correlations between the serum levels of cardiac markers and the oxidative stress markers in envenomed victims. In conclusions, oxidative stress occurs in scorpion envenomed children, but does not determine prognosis. Cardiac markers, but not the oxidative stress, remain the most important determining factor for the severity and the outcome of SE.

Incidence, mechanisms and impact outcome of hyperglycaemia in severe scorpion-envenomed patients

Hyperglycaemia is often observed in severe scorpion-envenomed patients. It is due to a severe autonomic storm with a massive release of catecholamines, increased glucagon levels, cortisol levels, and either decreased insulin levels or insulin resistance. The presence of hyperglycaemia is an indicator of severity in this specific condition. Indeed, hyperglycaemia was associated with the severity of clinical manifestations of severe scorpion envenomation requiring intensive care unit (ICU) admission. In fact, the presence of hyperglycaemia was associated with the presence of respiratory failure, pulmonary oedema, haemodynamic instability, neurological failure, multisystem organ failure, and an increased mortality and ICU length of stay. As a consequence, we think the presence of hyperglycaemia in scorpion-envenomed patients at the emergency department prompts searching for presence of systemic manifestations or cardiorespiratory manifestations. As a consequence, the presence of hyperglycaemia can help screen severe patients at the emergency department. The current management of severe scorpion envenomation involves the admission and close surveillance in the ICU, where vital signs and continuous monitoring enable early initiation of therapy for life-threatening complications. The use of antivenom for scorpion stings remains controversial. All patients with pulmonary oedema should receive prazosin and possibly dobutamine, according the scorpion's species. Mechanical ventilation is usually used in severe cases. Insulin should be reserved for severe cases with confirmed excessive hyperglycaemia (>10 mmol/l).

Saudi medicinal plants for the treatment of scorpion sting envenomation

Scorpion sting envenoming poses major public health problems. The treatment modalities include antivenoms, chemical antidotes and phytotherapy, with varying degrees of effectiveness and side effects. In this investigation, we reviewed the use of Saudi medicinal plants for the treatment of scorpion sting patients. The relevant literature was collected using the online search engines including Science Direct, Google and PubMed with the help of specific keywords. We also used the printed and online resources at our institutional library to gather the relevant information on the use of medicinal plants for the treatment of scorpion sting patients. A descriptive statistics was used for data compilation and presentation. The results of this survey showed the use of at least 92 medicinal plants with beneficial effects for treating victims of stings of different scorpion species. These commonly used herbs spanned to 37 families whilst different parts of these plants were employed therapeutically for alleviation of envenomation symptoms. The application of leaves (41%) was preferred followed by roots (19%), whole plant (14%) and seeds (9%). The use of latex (4%), stem (3%), flowers (3%) and bark (3%) was also reported. In some cases, tannin (2%), rhizome (1%) and shoot (1%) were also used. In conclusion, herbal medicines are effectively used for the treatment of patients with scorpion envenomation. This type of medication is free from side effects as observed with chemical antidotes or antivenom therapy. It is important to identify the active ingredients of herbal drugs for improving their therapeutic potential in traditional medicine.

Clinical and Epidemiological Aspects of Scorpionism in the World: A Systematic Review

OBJECTIVE

Scorpion stings are registered worldwide, but the incidence and the features of the envenomations vary depending on the region. The aim of this review was to summarize the epidemiological, clinical, diagnostic, and therapeutic data worldwide regarding humans stung by scorpions.

METHODS

A systematic review of the literature was conducted through the online databases of the Virtual Health Library (VHL), which hosts Medline and the Latin American and Caribbean Center on Health Sciences Informational (LILACS) database. We selected articles published between January 1, 2002 and July 31, 2014.

RESULTS

Scorpion envenomation reports were found throughout the world, mainly in subtropical and tropical regions. The clinical manifestations were sympathetically and parasympathetically mediated, depending on the species of scorpion. Some of the most common severe complications of scorpionism included respiratory distress syndrome, pulmonary edema, cardiac dysfunction, impaired hemostasis, pancreatitis, and multiple organ failure. Scorpion envenomation could be classified as mild, moderate, and severe, and the therapeutic approach was based on the case severity. The treatment comprised 3 components: symptomatic measures, vital functions support, and injection of antivenom. Moreover, the time that elapsed between the sting and administration of the appropriate medical care was extremely important to the patient's prognosis.

CONCLUSIONS

The large number of scorpion stings worldwide is concerning and reaffirms the need for new prevention measures and policies to reduce the incidence, prevalence, morbidity, and mortality rates from these poisonous arachnids.

Neurologic Complications in Children With Scorpionism: A Retrospective Study in Upper Egypt

Scorpion envenomation is a life-threatening health problem in tropical and subtropical regions, particularly among children. The aim of this study was to describe the epidemiologic characteristics, clinical profile, and prognosis of neurologic complications among children with scorpionism in Upper Egypt. In this retrospective study, the neurologic complications of scorpionism in 2 university hospitals were analyzed from the points of epidemiologic and clinical picture and outcomes. The neurologic manifestations were found at a high percentage (85%). Irritability was the main manifestation (83.4%), followed by sweating (81.5%), hyperthermia (33.6%), and priapism (48.2% of males). Moreover, convulsion and coma were found in 14.7% and 11% of children, respectively. Neurologic manifestations were common in children with scorpionism and they correlated with poor outcome. Identification of epidemiologic and clinical features of central nervous system complications of scorpionism in children provide important data, helping in development of management policies aiming at preventive control of scorpionism and decrease its mortality.

Scorpion-related cardiomyopathy and acute pulmonary edema in a child who is stung by Leiurus abdullahbayrami

Venom of Leiurus abdullahbayrami (Scorpiones: Buthidae) is an extremely toxic one and it stimulates voltage-gated sodium and potassium channels. In case of a stung by this scorpion; excessive catecholamine release occur and it impairs left ventricle contractility and consequently a heart failure occurs (scorpion sting-related cardiomyopathy). In addition to this cardiac-induced acute pulmonary, edema may occur in severe cases too. An 11-year-old male child who was stung by a scorpion (species: Leiurus abdullahbayrami) consulted to the Emergency Room. Even after 7 h of scorpion envenomation he was confused and having hallucinations. Besides he was dyspneic, tachycardic, hypotensive and got worse in overall situation due to cardiogenic pulmonary edema. These clinical findings are concordant with the Level III scorpion envenomation (major systemic manifestations). Positive inotropic agents, diuretics and antiagregant agents used on supportive therapy in his treatment. After 2 weeks he get recovered and discharged from the pediatric intensive care unit. This research is conducted by thinking emergency physicians should learn that Leiurus abdullahbayrami envenomation can cause scorpion-related cardiomyopathy and acute pulmonary edema especially in children.

Insights into the Hypertensive Effects of Tityus serrulatus Scorpion Venom: Purification of an Angiotensin-Converting Enzyme-Like Peptidase

The number of cases of envenomation by scorpions has grown significantly in Brazil since 2007, with the most severe cases being caused by the Tityus serrulatus scorpion. Although envenomed patients mostly suffer neurotoxic manifestations, other symptoms, such as hypertension, cannot be exclusively attributed to neurotoxins. Omics analyses have detected plentiful amounts of metalloproteases in T. serrulatus venom. However, the roles played by these enzymes in envenomation are still unclear. Endeavoring to investigate the functions of scorpion venom proteases, we describe here for the first time an Angiotensin I-Converting Enzyme-like peptidase (ACE-like) purified from T. serrulatus venom. The crude venom cleaved natural and fluorescent substrates and these activities were inhibited by captopril. Regarding the serum neutralization, the scorpion antivenom was more effective at blocking the ACE-like activity than arachnid antivenom, although neither completely inhibited the venom cleavage action, even at higher doses. ACE-like was purified from the venom after three chromatographic steps and its identity was confirmed by mass spectrometric and transcriptomic analyses. Bioinformatics analysis showed homology between the ACE-like transcript sequences from Tityus spp. and human testis ACE. These findings advance our understanding of T. serrulatus venom components and may improve treatment of envenomation victims, as ACE-like may contribute to envenomation symptoms, especially the resulting hypertension.

Opposing roles of LTB4 and PGE2 in regulating the inflammasome-dependent scorpion venom-induced mortality

Tityus serrulatus sting causes thousands of deaths annually worldwide. T. serrulatus-envenomed victims exhibit local or systemic reaction that culminates in pulmonary oedema, potentially leading to death. However, the molecular mechanisms underlying T. serrulatus venom (TsV) activity remain unknown. Here we show that TsV triggers NLRP3 inflammasome activation via K(+) efflux. Mechanistically, TsV triggers lung-resident cells to release PGE2, which induces IL-1β production via E prostanoid receptor 2/4-cAMP-PKA-NFκB-dependent mechanisms. IL-1β/IL-1R actions account for oedema and neutrophil recruitment to the lungs, leading to TsV-induced mortality. Inflammasome activation triggers LTB4 production and further PGE2 via IL-1β/IL-1R signalling. Activation of LTB4-BLT1/2 pathway decreases cAMP generation, controlling TsV-induced inflammation. Exogenous administration confirms LTB4 anti-inflammatory activity and abrogates TsV-induced mortality. These results suggest that the balance between LTB4 and PGE2 determines the amount of IL-1β inflammasome-dependent release and the outcome of envenomation. We suggest COX1/2 inhibition as an effective therapeutic intervention for scorpion envenomation.

Hyperglycemia is a risk factor for high-grade envenomations after European viper bites (Vipera spp.) in children

CONTEXT

Hyperglycemia has been described in severe scorpion envenomation, we wanted to analyze if it was applicable to viper bites in children.

AIM

To describe clinical, biological, and therapeutic characteristics of 83 children bitten by European viper (Vipera spp.) and to confirm that hyperglycemia is a risk factor for high-grade envenomation.

MATERIAL AND METHODS

A retrospective study was conducted between 2001 and 2014 in the pediatric emergency department of a tertiary level children's hospital. Collected data were: age and sex of children; day and time of admission; day, time and circumstances of the accident; snake identification; bite location; envenomation severity; presence of fang marks; prehospital care; laboratory abnormalities, use of specific immunotherapy, associated treatments; length of stay; hospital course.

RESULTS

Eighty-three children were included (62 boys, 21 girls). The mean age was 7.4 ± 3.9 years. Bites were most often located on the lower extremities (66%). The classification of envenomation was: 83% low grade (absent or minor envenomation) and 17% high grade (moderate to severe envenomation). All high-grade envenomations received specific immunotherapy (Viperfav(TM), (Aventis Pasteur, MSD, Lyon, France). Being bitten on an upper extremity (odds ratio [OR] 51.1 95% class interval [CI] [6.1-424], p < 0.0001), during the afternoon (OR 13.4 95% CI [1.7-107.9], p = 0.015), feeling violent pain (OR 4.2 95% CI [1.1-16.5], p = 0.023), and high initial plasma glucose level (6.5 ± 1.7 mmol/L versus 5.0 ± 0.9 mmol/L, p = 0.027) were associated with a significant risk of high-grade envenomation.

CONCLUSION

We have confirmed a potential link between initial hyperglycemia and the risk of progression to high-grade envenomation as well as its association with other published predictive factors.

Immunomodulatory activity of Tityus serrulatus scorpion venom on human T lymphocytes

Background

Tityus serrulatus scorpion venom (TsV) contains toxins that act on K⁺ and Na⁺ channels and account for the venom’s toxic effects. TsV can activate murine peritoneal macrophages, but its effects on human lymphocytes have been poorly investigated. Considering that lymphocytes may play an important role in envenomation, we assessed whether TsV affects the expression of phenotypic (CD3, CD4, and CD8) and activation (CD69, CD25, and HLA-DR) markers, cell proliferation, and cytokine production in peripheral blood mononuclear cells.

Methods

Cytotoxicity of TsV was evaluated via the MTT assay. Cell proliferation, expression of phenotypic and activation markers, and release of cytokines were assessed using flow cytometry, after treatment with non-cytotoxic concentrations of TsV. The combined use of carboxyfluorescein diacetate succinimidyl ester and monoclonal antibodies against phenotypic and activation markers enabled us to simultaneously assess cell proliferation extent and cell activation status, and to discriminate among cell subpopulations.

Results

TsV at concentrations of 25 to 100 μg/mL were not cytotoxic towards peripheral blood mononuclear cells. TsV did not induce significant changes in lymphocyte subpopulations or in the expression of activation markers on CD4⁺ and CD8⁺ T cells. TsV inhibited the phytohemagglutinin-stimulated lymphocyte proliferation, particularly in the CD8⁺ CD25⁺ T lymphocyte subset. TsV alone, at 50 and 100 μg/mL, did not induce peripheral blood mononuclear cell proliferation, but elicited the production and release of IL-6, a proinflammatory cytokine that plays an important role in innate and adaptive immune responses.

Conclusions

TsV is a potential source of molecules with immunomodulatory action on human T lymphocytes.

Electronic supplementary material

The online version of this article (doi:10.1186/s40409-015-0046-3) contains supplementary material, which is available to authorized users.

Predictive Factors for Determining the Clinical Severity of Pediatric Scorpion Envenomation Cases in Southeastern Turkey

OBJECTIVE

The aim of this study was to define the epidemiological, clinical, and laboratory manifestations of scorpion envenomation and to identify factors that are predictive of severe cases.

METHODS

The medical files of 41 scorpion envenomation cases were reviewed retrospectively. The cases were classified as mild-moderate or severe. The epidemiological, clinical, and laboratory findings of patients were recorded.

RESULTS

There were 27 patients (65.9%) in the mild-moderate group and 14 patients (34.1%) in the severe group. The median age of all patients was 48 months. The most common systemic finding was cold extremities (41.5%). In all patients, the most commonly observed dysrhythmia was sinus tachycardia (34.1%). Two patients (4.9%) had pulseless ventricular tachycardia and died. Pulmonary edema and myocarditis were observed in 9 patients (22%). Median values of leukocyte and glucose levels were markedly increased in the severe group. Additionally, the mean thrombocyte level (540,857 ± 115,261 cells/mm(3)) in the severe group was significantly increased compared with the mild-moderate group (391,365 ± 150,017 cells/mm(3)). Thrombocyte levels exhibited a positive correlation with leukocyte and glucose values and a negative correlation with patient left ventricular ejection fraction. Multivariate analysis of laboratory parameters indicated that the most predictive factor for clinical severity is thrombocytosis (odds ratio 23.9; 95% CI: 1.6-353.5, P = .021).

CONCLUSIONS

Although our results share some similarities with those of other reports, thrombocytosis was markedly increased in the severe group and served as the most predictive laboratory factor of clinical severity.

Endocrinological and biochemical changes of scorpionism in children in Upper Egypt

AIM

The aim of this study was to determine some endocrinological and biochemical changes of scorpionism in children in Upper Egypt. In addition, it aimed to find any possible relationship between these changes and the severity of scorpionism.

PATIENTS AND METHODS

The present study was carried out at two university hospitals in Upper Egypt and included 42 children with envenomation and 20 apparently healthy children as controls. In all subjects, levels were measured of noradrenaline, aldosterone, insulin and cortisol, and some biochemical parameters and electrolytes including nitric oxide (NO), creatine phosphokinase (CPK), Na+ and K+.

RESULTS

Na+, NO and CPK levels were significantly higher in children with envenomation compared with the controls. Also, there was a significant reduction in K+ in patients compared with controls. Children with severe envenomation had significantly higher levels of noradrenaline, cortisol and aldosterone compared with the controls and mild cases. However, insulin levels were significantly decreased in severe cases of scorpionism compared with mild ones. Moreover, hyperglycemia was detected in all patients with envenomation compared with controls, with significantly higher blood glucose levels among children with severe envenomation compared with mild cases.

CONCLUSION

Endocrinological changes were common in all children with scorpion envenomation and more obvious in cases of severe envenomation. The released mediators may account for several inflammatory manifestations such as pulmonary edema, myocardial failure, systemic inflammatory response syndrome and multiple organ failure. The use of insulin is recommended in cases of severe envenomation to improve the outcome.

Doxazosin in the treatment of scorpion envenomation

OBJECTIVE

To investigate effectiveness and applicability of Doxazosin in the treatment of scorpion stings in patients who had systemic symptoms.

METHODS

The medical records of patients were retrospectively reviewed, and the following data were collected: age, sex, clinical symptoms (localized and systemic), vital signs, information on the date and place of the sting occurrence, the anatomical sting site, time between sting and arrival to the hospital, scorpion identification, severity of the symptoms and treatment.

RESULTS

Of the victims, 48.5 % (n = 16) were males, and 51.5 % (n = 17) were females, with a mean age of 6.8 ± 4.2 y. The most common sting site was lower extremity 72.7 % (n = 24). Systemic toxicity (class II) was seen in 93.9 %, and two patients (6.1 %) manifested evidence of severe envenomation (class III). Both local and systemic effects were seen in the patients. Cold extremities persisted for 4.5 ± 1.5 h after administration of Doxazosin. Mean hospitalization time was 2.5 ± 1.5 d (range: 1.5 to 6 d). Thirty-two patients recovered without any sequel, whereas one patient died due to cardio-pulmonary insufficiency.

CONCLUSIONS

Doxazosin, especially if Prazosin is not available, can be recommended as an effective drug in the treatment of serious scorpion envenomations with significant sympathetic symptoms.