Endocrinological and biochemical changes of scorpionism in children in Upper Egypt

DNA Barcoding for Scorpion Species from New Valley Governorate in Egypt Reveals Different Degrees of Cryptic Speciation and Species Misnaming

(1) Background: Scorpions (Arthropoda: Arachnida) represent a diverse group of invertebrates, accounting for a significant proportion of earth’s predators and ecosystems’ modulators. Surviving mostly in hardly reachable nests, and representing key hazards to human health, they attracted major interest for characterizing their eco-, morpho-, and genotypes. (2) Methods: Four scorpion species were collected from the New Valley governorate in Upper Egypt, where a high level of scorpionism and related neurological symptoms are found, that were Leiurus quinquestriatus, Androctonus amoreuxi, Orthochirus innesi, Buthacus leptochelys. They were DNA barcoded, genetically and phylogenetically analyzed through PCR amplification and sequencing of the mitochondrial cytochrome oxidase subunit 1 (COI) gene hypervariable 5′ region. (3) Results: New, morphologically authenticated scorpion barcodes could be added to the barcoding databases. However, several discrepancies and barcode database inadequacies could be revealed. Moreover, taxon-specific patterns for nitrogenous bases’ distribution could be identified, resulting in a significantly high percentage of COI barcode guanine in scorpionids, in comparison to araneids and opilions. (4) Conclusions: For a group of animals where both cryptic speciation and a high risk of human envenomation are evident, the findings of the current study strongly recommend continuous and comprehensive research efforts dealing with morphogenetic authentication for different species of scorpions.

The lethality, histological, haematological and biochemical alterations in mice envenomated with Aegaeobuthus nigrocinctus venom

There is currently no data regarding the toxicity or the in vivo effects of the venom the Aegaeobuthus nigrocinctus species, since it has not been studied thus far according to the best of our knowledge. In the present study, and for the first time, the median lethal dose, the in vivo toxic effects, the histological changes in some of the vital organs were all determined as well as an assessment was made of the histological, biochemical and haematological changes which were caused by the venom injected in mice. The median lethal dose (LD₅₀) of the scorpion venom for mice was found to be 0.38 mg/kg in terms of body weight. The results of the study show that the A. nigrocintus is a potentially lethal scorpion. The evidence related to the venom indicated that it could cause tissue injury in some vital organs. In conclusion, this scorpion venom could cause significant medical complications, and may lead to death, regarding at-risk patients. Therefore, health professionals should be aware of the various scorpion species in their regions and should follow current medical approaches concerning scorpion envenomation.

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.

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.

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).

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.