Risk factors for high-grade envenomations after French viper bites in children

Venomous snakebites in children: a 10 year experience in South China

INTRODUCTION

Many studies have focused on snakebites in adults, but very few have described snakebites in children.

METHODS

We reviewed the clinical characteristics and outcomes of children with venomous snakebites aged less than 15 years who presented to a regional medical centre in South China from January 2013 to December 2022.

RESULTS

A total of 69 envenomed patients were analyzed in our study; 42 (60.9 per cent) patients were male, and 59 (85.5 per cent) reported lower limb bites. Most bites (89.8 per cent) occurred between April and October. Twenty-seven patients received first aid management, and 47 required admission to the general ward. Antivenom was administered to 58 patients, glucocorticoids to 43 patients, antibiotics to 48 patients, and tetanus antitoxin to 40 patients. No fatalities were reported. The most common snake identified was Trimeresurus albolabris. Four were classified as dry bites, 15 as mild, 43 as moderate, and seven as severe. The most common local signs were pain and swelling, while the most common systemic effects were haematological complications. Patients with high severity scores had significantly higher lactate dehydrogenase activities, creatine kinase isoenzyme activities, aspartate aminotransferase activities, D-dimer concentrations, prothrombin times and lower fibrinogen concentrations. In a receiver operating characteristic curve analysis of the values with the highest Youden index, the following cut-offs proved significant: lactate dehydrogenase activity > 248.1 U/L, creatine kinase isoenzyme activities > 17.5 U/L, fibrinogen concentration < 1,455 mg/L, D-dimer concentration > 437.0 µg/L, aspartate aminotransferase activity > 26.1 U/L, and prothrombin time > 15.2 seconds.

DISCUSSION

This study provides insight into the epidemiology, clinical profile, and management of snakebites in children. Data from the present study were compared with those from our previous adult study. Limitations include that 50.7 per cent of our snakebites were attributed to Trimeresurus albolabris. Therefore, the results of our study may not be generalizable to all snakebites.

CONCLUSION

The clinical symptoms were more severe in children than in adults in our previous study. Even though there were no fatalities, close monitoring should be performed to detect haematological and other potentially fatal complications promptly.

Most adder bites in Finland's Lake District caused mild symptoms and severe poisoning was rare

AIM

This study investigated the incidence, clinical picture and treatment of paediatric adder bites in Finland's Lake District.

METHODS

Data were retrospectively collected on all children aged 0-15 years who were bitten by adders from 2006 to 2015 and treated at Tampere University Hospital. The severity was evaluated with the five-level Poisoning Severity Score.

RESULTS

We found that 109 children were treated following an adder bite, which was an incidence of 13 per 100,000 children from 0 to 15. Of these, 75 were under 8 years of age, with a median age of 3.5 years, and 34 were 8-15 years, with a median age of 10.3 years. The gender distribution was similar in both ages. Younger children were more likely to be bitten in their yards at home, whereas older children were more likely to be bitten in a forest. Older children reported more pain than younger patients. Most children were bitten on a lower limb, with minor symptoms such as localised redness and swelling, and received conservative treatment. Antivenom treatment was rarely administered and then only in severe cases or if symptoms progressed.

CONCLUSION

Adder bites mostly caused mild symptoms, severe poisoning was rare and antivenom was rarely given.

Echis coloratus envenomation in children: a retrospective case series

BACKGROUND

Antivenom has been used successfully to treat systemic and progressive, local manifestations of envenomations inflicted by Echis coloratus, the second most common cause of snake envenomation in Israel. There is a paucity of published data regarding the use of monovalent (equine) immunoglobulin G antivenom in children. This study describes outcomes from the regimen used in two large, tertiary care pediatric centers.

METHODS

A retrospective chart review of children admitted with definite or probable signs of Echis coloratus envenomation to Sourasky (Tel Aviv) and Soroka (Be'er Sheva) Medical Centers from January 1st 2008-to June 1st 2019. Extracted data included age, location of bite, time to hospital arrival, laboratory test results, complications, time to antivenom administration if indicated, adverse effects of the antivenom, and outcomes. Indications for antivenom were: diagnosis of Echis coloratus as the etiology of envenomation, local and systemic signs e.g. skin puncture wounds, swelling of the involved limb, local hematoma, and abnormal coagulation blood test results.

RESULTS

During the study period, 11 children were treated with intravenous Echis coloratus antivenom. Median age was 9 years and 10 of 11 patients were male. Two patients underwent fasciotomy; in one, compartment syndrome was diagnosed by pressure measurement, and in the second, clinically. One patient developed mild urticaria 30 min after initiation of the antivenom; the treatment was stopped and then restarted at a slower rate after he was treated with hydrocortisone and diphenhydramine. No further adverse reactions were observed.

CONCLUSIONS

In children, Echis coloratus antivenom appeared to be effective and safe for the treatment of systemic and progressive local manifestations of envenomation by Echis coloratus.

Acute Exposure to European Viper Bite in Children: Advocating for a Pediatric Approach

Viper bite is an uncommon but serious cause of envenoming in Europe, especially in children. Our study aim is to better describe and analyze the clinical course and treatment of viper bite envenoming in a pediatric population. We retrospectively reviewed 24 cases of pediatric viper bites that were admitted to the Pediatric Emergency Department and the Pediatric Intensive Care Unit of the Bambino Gesù Children Hospital in Rome between 2000 and 2020. Epidemiological characteristics of the children, localization of the bite, clinical and laboratory findings, and treatment approaches were evaluated. The median age of the patients was 4.2 years, with male predominance. Most cases of viper bite occurred in the late summer. Most patients required admission to the ward for prolonged observation. The most common presenting signs were pain, local oedema, and swelling. Patients with a high severity score also had a significantly higher white blood cell count and an increase of INR, LDH, and CRP levels. No fatality was reported. Viper bite envenomation is a rare pediatric medical emergency in Italy but may sometimes be severe. A new pediatric severity score may be implemented in the screening of children with viper bites to favor a selective and prompt administration of antivenom.

Vipers of Major clinical relevance in Europe: Taxonomy, venom composition, toxicology and clinical management of human bites

Snakebites in Europe are mostly due to bites from Viperidae species of the genus Vipera. This represents a neglected public health hazard with poorly defined incidence, morbidity and mortality. In Europe, fourteen species of "true vipers" (subfamily Viperinae) are present, eleven of which belong to the genus Vipera. Amongst these, the main medically relevant species due to their greater diffusion across Europe and the highest number of registered snakebites are six, namely: Vipera ammodytes, V. aspis, V. berus, V. latastei, V. seoanei and V. ursinii. Generally speaking, viper venom composition is characterised by many different toxin families, like phospholipases A2, snake venom serine proteases, snake venom metalloproteases, cysteine-rich secretory proteins, C-type lectins, disintegrins, haemorrhagic factors and coagulation inhibitors. A suspected snakebite is often associated with severe pain, erythema, oedema and, subsequently, the onset of an ecchymotic area around one or two visible fang marks. In the field, the affected limb should be immobilised and mildly compressed with a bandage, which can then be removed once the patient is being treated in hospital. The clinician should advise the patient to remain calm to reduce blood circulation and, therefore, decrease the spread of the toxins. In the case of pain, an analgesic therapy can be administered, the affected area can be treated with hydrogen peroxide or clean water. However, anti-inflammatory drugs and disinfection with alcohol or alcoholic substances should be avoided. For each patient, clinical chemistry and ECG are always a pre-requisite as well as the evaluation of the tetanus immunisation status and for which immunisation may be provided if needed. The treatment of any clinical complication, due to the envenomation, does not differ from treatments of emergency nature. Antivenom is recommended when signs of systemic envenomation exist or in case of advanced local or systemic progressive symptoms. Recommendations for future work concludes. The aim of this review is to support clinicians for the clinical management of viper envenomation, through taxonomic keys for main species identification, description of venom composition and mode of action of known toxins and provide a standardised clinical protocol and antivenom administration.

Vipera snakebite in Europe: a systematic review of a neglected disease

In 2009, snakebites were included in the list of the World Health Organization (WHO) neglected diseases. Dermatological literature lacks current and up-to-date articles about snakebites and their management, despite the fact that dermatologists, especially from rural hospitals, can be called into the emergency room to consult the management of suspected snakebites. In this systematic review, we highlighted the main clinical and laboratory aspects of snakebites from Vipera spp. in Europe, by reviewing 3574 studies initially retrieved from PubMed, Embase and Cochrane CENTRAL databases. Of these, 78 were finally included in the systematic review. We found that the most involved taxon was V. berus in 63.3% and the most involved anatomic site of the bite was the upper limbs 53.1% with fang marks reported in 90.5%. The mean age of the patients was 32.9 years, and bites were slightly more common among males (58.2%). A wound washing was performed in 86.9% of cases before the hospitalization. The most frequently reported grade of envenomation was G2 (42.2%). In addition to local dermatological symptoms (extended erythema, oedema, cutaneous necrosis, hives, purpura, petechiae, acute compartment syndrome), numerous systemic symptoms have also been reported, including fatigue (14.4%), pain (75.3%), fever (49.2%), direct anaphylactoid reaction (5.3%), anxiety (60.8%), cranial nerve neurotoxicity (14.8%), dysesthesia/paraesthesia (7.9%), vomiting (33.7%), abdominal pain (23.3%), diarrhoea (15.4%), dyspnoea (6.3%), proteinuria (10.6%) and haematuria (9.3%). Secondary infections were present in 3.5% and disseminated intravascular coagulation in 3.1% of cases, and fasciotomy was performed in 4.2% cases, while an amputation in 6.9%. Only 0.9% of patients died. Antivenom was administered in 3053 cases. In conclusion, there is a pressing need for robust multi-centre randomized control trials, standardized protocol for snakebite management and antivenom administration across Europe and a National snakebite register for each European country.

Antivenom for European Vipera species envenoming

BACKGROUND

European viper bite is relatively uncommon but can cause serious envenoming, particularly swelling and hemorrhage spreading from limb to trunk that can cause long term disability. Systemic features are relatively mild compared to many other venomous species. Moderate-to-severe envenoming requires antivenom, which is given many hundreds of times each year across the continent. Several Vipera spp antivenoms are produced in Europe, but there is little comparative information available for the antivenoms and none is licensed with the European Medicines Agency. We aimed to collect descriptive data on European viper antivenoms and assess their relative effectiveness.

METHODS

A systematic review of articles relating to antivenom in Europe was performed using the Medline medical database. The following keywords "Europ*" or the individual names of each European country and "antiven*" or "immun*" or "envenom*" and "snake" or "viper*" or "adder" were used. Articles published between 1 January 1996 and 11 March 2016 pertaining to clinical outcome, including case reports, were selected. Referenced articles in the indexed articles were explored for suitability and included if they met any of the criteria: specific antivenom used, route of antivenom administration, adverse reactions to antivenom therapy and length of hospital admission. All accepted abstracts from EAPCCT conferences since 2000 were searched and abstracts relating to Vipera spp envenoming were assessed for suitability. We extracted data on study type, safety and effectiveness. We sought information on antivenoms from manufacturers and individual patient data from authors of publications. Since individual patient data were only rarely available, we compared median length of stay between case series reporting each antivenom. We identified 40 papers and six published abstracts, and one unpublished paper that reported clinical cases and case series of envenomed patients treated with antivenom. No publication reported randomized controlled trials comparing any European Vipera antivenom with either placebo or another antivenom. 25 reports were of retrospective hospital- (n = 13) or poison center-based (n = 12) case series including five or more patients; a further 12 reports were either case reports or case series with less than five patients and one paper was a limited literature review. An additional nine papers reported prospective data; seven collected data remotely through poison service telephone communication with the attending physicians. Antivenoms available in Europe: Eight antivenoms are available for European Vipera spp envenoming; a material safety data sheet providing information on manufacture was available for seven. Six are raised against V. berus or V. ammodytes venom; the seventh is raised against a mixture of V. ammodytes, V. aspis and V. berus venom and the eighth is raised against V. ammodytes, Macrovipera lebetina and Montivipera xanthina venom. Six manufacturers recommended intramuscular administration while two recommended intravenous administration. No randomized control trials comparing the effectiveness of antivenoms were identified. Pre-clinical data: We found two papers presenting comparative preclinical data. Clinical data: Clinical studies were predominantly retrospective and contained clinical data on antivenom used in 2602 patients; where the antivenom was identified (n = 2174), 2061 (94.8%) received Zagreb, ViperFAV or ViperaTAb antivenoms. There were few published data on the other antivenoms. Repeated use of antivenom: Repeat doses were reported in 230/1491 of cases (15.4%) where this information was recorded. Outcome and length of hospital stay: Intravenous administration of antivenom was associated with shorter length of hospital stay (median length of hospital stay in studies of intravenous ViperFAV or ViperaTAb ranged from 1 to 4.8 days versus 2 to 18 days for intramuscular Bulbio or Zagreb antivenoms). Antivenom versus no antivenom: Some small studies demonstrated no difference in the length of hospital stay in patients with equivalent envenomation grading who either did or did not receive antivenom. Adverse events: Adverse reactions were reported in 37 of 2408 cases (1.5%) including seven cases of anaphylaxis.

CONCLUSIONS

There are very limited pre-clinical comparative data and no randomised controlled trials assessing effectiveness of the antivenoms against different Vipera species. Most descriptive data suggest the efficacy of Zagreb, ViperFAV and ViperaTAb antivenoms by the intravenous route but not intramuscular route, although this is level D evidence. Reported adverse reactions were rare, suggesting that the modern intravenous antivenoms are of good quality. Better and more systematic data, including perhaps randomized controlled trials comparing different antivenoms, are required for the many hundreds of antivenom administrations that occur annually across Europe.

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.