Clinical characteristics and outcome of children stung by scorpion

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.

Pediatric scorpionism in northern Amazonia: a 16-year study on epidemiological, environmental and clinical aspects

Background:

The Amazon basin is one of the seven major geographical areas where scorpionism is recorded. In French Guiana, 90 stings per 100,000 inhabitants are registered per year. As the severity of cases is higher in children, descriptive studies are needed to have a better understanding of this pathology. The aim of the present study is to describe pediatric scorpionism in French Guiana.

Methods:

We conducted a monocentric descriptive retrospective study on scorpion stings in all pediatric patients admitted to Cayenne General Hospital from January 1, 2002 to December 31, 2018.

Results:

In this survey, 132 patients were included. Of them, 63% were male. Patients with general signs of envenomation were younger and lighter (p = 0.04). The picture was “one sting” (95.3%) by a “big” (47.6%), “black” (60%) and “small pincer” (58%) scorpion on the extremity of the body (84%). Stings occurred mainly during the day, while patients changed clothes. There was no envenomation during night. The monthly evaluation highlights that the number of stings and percentage of general signs of envenomation were closely connected to a composite variable including the variation of the level of rivers (p = 0.005). Cardiac symptoms were recorded in 82% of cases with general signs of envenomation. The presence of pulmonary; ear, nose, and throat (ENT); or gastrointestinal symptoms are related to major envenomation (p = 0.001, p = 0.01, and p = 0.02 respectively). Leukocytosis and glycemia increased according to the envenomation grade whereas serum potassium and alkaline reserve decreased. Forty-six patients needed hospitalization and seven of them required intensive care. No patient died nor presented sequelae at discharge from the hospital.

Conclusion:

Pediatric scorpionism in French Guiana is closely associated with child activities and climatic conditions. Severe envenomation presented most of the time with cardiac, pulmonary, and gastrointestinal symptoms.

Determination of hyaluronidase activity in Tityus spp. Scorpion venoms and its inhibition by Brazilian antivenoms

Hyaluronidases (HYALs) are enzymes ubiquitously found in venoms from diverse animals and seem to be related to venom spreading. HYAL activity might be important to Tityus spp. envenoming, since anti-Tityus serrulatus HYAL (TsHYAL) rabbit antibodies neutralize T. serrulatus venom (TsV) lethality. The present work aimed to verify and compare HYAL activity of venoms from other Brazilian Tityus spp. (Tityus bahiensis, Tityus stigmurus and Tityus obscurus) and to test whether anti-TsHYAL antibodies and Brazilian horse therapeutic scorpion antivenom (produced by Fundação Ezequiel Dias (FUNED), Butantan and Vital Brazil Institutes) can recognize and inhibit HYAL activity from these venoms. In ELISA assays, anti-TsHYAL and scorpion antivenoms recognized T. serrulatus, T. bahiensis and T. stigmurus venoms, however, they demonstrated weaker reaction with T. obscurus, which was also observed in Western blotting assay. Epitope mapping by SPOT assay revealed different binding patterns for each antivenom. The assay showed a weaker binding of scorpion antivenom produced by FUNED to peptides recognized by anti-TsHYAL antibodies. Anti-TsHYAL antibodies and antivenoms produced by Butantan and Vital Brazil institutes inhibited HYAL activity of all tested venoms in vitro, whereas FUNED antivenom did not show the same property. These results call attention to the importance of hyaluronidase inhibition, that can aid the improvement of antivenom production.

A randomized comparative study between intravenous and intramuscular scorpion antivenom regimens in children

BACKGROUND

Scorpion envenomation and its consequences represented a serious healthcare problem in Upper Egypt and considered to be an important cause of life-threatening emergency particularly in children.

METHODS

One hundred patients presented to the emergency department of Assiut University Children Hospital with a history of scorpion sting aged less than 18 years were included in our randomized comparative trial during 2016. Two groups of patients were randomly categorized according to the route of administration of scorpion antivenom; intramuscular and intravenous with 50 patients in each group. Full history, clinical examination, and routine baseline investigations were performed.

RESULTS

Myocarditis, encephalopathy, cardiogenic shock, ICU admission, need for mechanical ventilation, mean hospital stay and mortality were significantly lower in those received intravenous antivenom compared with those received intramuscular one.

CONCLUSION

The results of the present study and other experimental and clinical trials confirmed that the administration of the scorpion antivenom by intravenous route has a lower incidence of systemic toxicity, a better outcome of fatal complication resulted from envenomation especially cardiogenic shock, decreased need for ICU facilities and mechanical ventilation, shorter hospital stay, and better overall outcome than the intramuscular route.

TRIAL REGISTRATION NUMBER

UMIN-CTR Study Design: trial number: UMIN000022032.

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.

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.

Role of some vasoactive mediators in scorpion envenomed children: Possible relation to envenoming outcome

Scorpion envenomation causes an autonomic storm resulting in changes in the vasoactive mediators' levels which lead to myocardial damage, cardiovascular disturbances, peripheral circulatory failure, pulmonary edema, multi-system-organ-failure and death. The study aimed to determine the circulating levels of adrenaline, noradrenaline, angiotensin converting enzyme (ACE), Angiotensin II (Ang II), kallikrein enzyme, nitric oxide (NO), aldosterone, and electrolytes Na⁺, K⁺ and Ca⁺² in scorpion envenomed children and to evaluate the potential relation between these vasoactive mediators, the severity of scorpion envenoming and the clinical outcome of envenomed children. Forty envenomed children (22 mild and 18 severe cases) along with 10 healthy control children were enrolled in the study. The circulating levels of adrenaline, noradrenaline, Ang II, ACE, kallikrein enzyme, and NO were determined by ELISA, and spectrophotometric assays on admission and 24 h later. On admission, serum aldosterone, and electrolytes; Na⁺, K⁺ and Ca⁺² were determined by RIA, Flame photometer and Flame atomic absorption respectively. All envenomed children showed significant surge of adrenaline, noradrenaline, ACE, Ang II, aldosterone, NO and Na⁺, that concomitantly faced by significant reduction in kallikrein, K⁺ and Ca⁺² on admission. Twenty four hours later, all envenomed children continued to show significant elevation of ACE, Ang II and NO. The severely envenomed children showed considerable reduction in circulating levels of adrenaline, noradrenaline, ACE and Ang II, while dramatic increase in kallikrein activity was reported in comparison to mildly envenomed children after 24 h of medical care. Also, NO exhibited considerable accumulation in non survivors, on admission, that was persistent for the subsequent 24 h and was accompanied by high kallikrein, low catecholamines and Ang II levels compared to survivors. Finally, the hypertensive cases showed substantial higher levels of catecholamine, ACE and Ang II, 24 h after admission. These findings indicated that, disturbances of the studied vasoactive mediators were common in scorpion envenomed children and may account for several inflammatory manifestations and clinical outcome. ACE inhibitors could be considered as possible therapeutic agent in victims with prominent increase in ACE and Ang II while kallikrein inhibitor and antioxidants may be effective in the treatment of late hypotensive ones.

Serum level of scorpion toxins, electrolytes and electrocardiogram alterations in Mexican children envenomed by scorpion sting

The scorpion Centruroides limpidus limpidus (C.l.l.) is endemic in México, producing hundreds of accidents in humans; children being one of the most susceptible targets. Few studies reported that severe envenoming by scorpion venom induces cardiac damage and electrolytes abnormalities in children, but the relationship of envenoming severity and toxic blood levels is unknown. The aim of this study was to determine the relationship among clinical status of envenoming, serum electrolyte, electrocardiographic abnormalities, and serum toxin levels in 44 children stung by scorpion over a period of 6 months in the State of Morelos, Mexico. The patients were said to be asymptomatic, when they presented just local symptoms, and were said to be symptomatic when showing local symptoms and at least one systemic symptom. The clinical status was evaluated at the admission at the emergency room of the Hospital, and 30 min after the administration of polyspecific F(ab')2 anti-scorpion therapy to symptomatic children. Forty-one percent of the children were asymptomatic and 59% symptomatic. Potassium and sodium imbalance and an elongation of the QT interval were detected; the rate of hypokalemia was higher in symptomatic than on asymptomatic children (50% and 6%, respectively). Hypokalemia persisted in 19% in symptomatic patients, whereas sodium reached normal levels 30 min after anti-venom therapy. The hypokalemia statistically correlated with elongation of the QT interval. The concentration of the toxic components of C.l.l in serum was significantly higher in symptomatic than asymptomatic children, and the serum levels of the toxic component significantly decreased to undetectable levels after the application of anti-venom therapy. Despite the small size of the sample, this study establishes that severity of envenoming was statistically related to potassium imbalance in serum, QT interval and the concentration of toxic components in serum, which decreased at undetectable levels after specific treatment with the anti-scorpion venom, correlating with clinical disappearance or greatly reduction of symptoms of envenomation.

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.