Varespladib mitigates acute liver injury via suppression of excessive mitophagy on Naja atra envenomed mice by inhibiting PLA2

Snakebite envenomation often leads to severe visceral injuries, including acute liver injury (ALI). However, the toxicity mechanism remains unclear. Moreover, varespladib can directly inhibit phospholipase A2 (PLA2) in snake venom, but its protective effect on snakebite-induced ALI and the mechanism have not been clarified. Previous studies have shown that snake venom PLA2 leads to neuron cell death via reactive oxygen species (ROS), one of the initial factors related to the mitophagy pathway. The present study group also found that ROS accumulation occurred after Naja atra envenoming. Hematoxylin and eosin (H/E) staining and immunohistochemistry (IHC) were performed to identify the expression of inflammatory factors in the liver tissue, and flow cytometry and immunofluorescence were used to detect ROS levels and mitochondrial function. Immunofluorescence and western blotting were also used for detecting mitophagy pathway-related proteins. The results showed that N. atra bite induced ALI by activating mitophagy and inducing inflammation and that varespladib had a protective effect. Collectively, these results showed the pathological mechanism of ALI caused by N. atra bite and revealed the protective effect of varespladib.

Acute compartment syndrome and fasciotomy after a viper bite in Italy: a case report

BACKGROUND

Bites caused by European vipers are rare medical emergencies but can occasionally cause life-threatening complications. Viper venom causes local symptoms, which can be accompanied by systemic manifestations in severe cases. The local effects of snakebites include edema and, more rarely, necrosis and compartment syndrome. The consequences of envenomation are often more pronounced in children due to their smaller body size.

CASE PRESENTATION

We present the case of a 6-year-old girl who experienced multiple viper bites in the lower limb in northwest Italy. The girl received supportive care but progressed to develop compartment syndrome that required emergency fasciotomy. The patient's condition improved promptly after surgical decompression and administration of antivenom, but full recovery required prolonged hospitalization and rehabilitation.

CONCLUSIONS

This case highlights the importance of obtaining a timely assessment of the severity of viper envenomation without delaying the administration of antivenom in most serious cases. The presence of multiple bite marks on the patient is one factor that may help to predict the clinical severity of snakebites and anticipate symptom progression.

Clinical characteristics of snakebite patients attending a tertiary hospital in Hangzhou, southeast China

BACKGROUND

Venomous snakebite is a neglected yet an important public health problem in China, and few studies have focused on them so far. The aim of this study is to investigate clinical characteristics of snakebites patients in a tertiary hospital in Hangzhou, southeast China.

METHODS

A total of 416 snakebite cases were included in this retrospective study. The data were collected from the medical records including demographics, clinical manifestations, management and outcomes.

RESULTS

Of the 416 patients with venomous snakebites, 248 were male, and the average age was 54.6 years. The majority of cases occurred in rural in May to September. Out of all the venomous bites, Gloydius brevicaudus accounted for the highest percentage (55.3%). Hands were the most vulnerable site to snakebites (47.4%). Patients had clinical manifestations of pain (100%), swelling (100%), wound necrosis (25.7%), hemorrhagic blister (18.3%), and blister (8.7%). Three hundred and ninety-two patients received antivenom administration, and most were treated within six hours after bites. Twenty-six patients received surgical treatments, and 90 patients developed venom-induced consumption coagulopathy. No deaths have occurred in this study.

CONCLUSION

Hangzhou is one of the regions with high affecting of snakebites in China. The results of this study will increase the understanding of the clinical characteristics of venomous snakebites in Hangzhou area.

Snake Envenomation

Snakebite envenomation (SBE) in horses can have devastating outcomes. Tissue damage, cardiotoxicity, coagulopathy, and neurotoxicity can be concerns with SBE. Understanding the actions of venom components is important in developing a successful treatment plan. Antivenom is the mainstay of treatment. Long-term deleterious effects can occur including cardiac dysfunction and lameness.

Peripheral Nerve Block to Treat Pain Caused by Daboia palaestinae Envenomation

Snakebite pain can be challenging to control. We describe our experience managing intolerable pain after conventional treatment failed. A 35-year-old man, presented after a viper snakebite, suffering from intolerable pain in the affected extremity. He had no significant past medical history. All attempts to control the pain conventionally were unsuccessful. Treatment with a supraclavicular nerve block resulted in immediate relief. After the block receded, only a dull pain remained, which later disappeared without recurrence. This experience illustrates the need for personalized pain treatment to avoid subsequent complications.

Moderately severe acute pancreatitis after snake bite: a case report from Southern China

Venomous snakebites are not rare worldwide, and this is also the situation in the mountainous regions of southern China, where they pose a serious health risk to the local population. Snake venom usually causes a variety of clinical symptoms, such as local pain and swelling, systemic coagulation system abnormalities, and shock, but rarely leads to acute pancreatitis. In this report, we presented a rare case of moderately severe acute pancreatitis caused by snake venom even after prompt antivenom treatment. The patient was relieved, obviously, with effective treatment of acute pancreatitis and was discharged without severe complications. Although acute pancreatitis after snake bite is a rarity, its serious complications and lethality still deserve our utmost attention, and timely and standardized treatment of acute pancreatitis is needed in addition to antivenom treatment.

The kidney histopathological spectrum of patients with kidney injury following snakebite envenomation in India: scoping review of five decades

INTRODUCTION

Snakebite is a public health problem leading to about 58,000 deaths every year in India. Kidney injury subsequent to snakebite envenomation is common with a reported prevalence of up to 32%. The current study aims to elucidate the spectrum of kidney histopathology in acute kidney injury (AKI) cases associated with snake bites.

METHODS

We searched seven electronic database studies to identify studies describing the histopathological findings in the kidney with snakebite envenomation. Two reviewers independently conducted titles and abstract screening as well as full-text evaluation for the final inclusion decision. Data were extracted as per the standardized form. We conducted narrative synthesis. Studies done exclusively on autopsy findings, in vitro studies, and case reports were excluded.

RESULTS

We retrieved 1464 studies and finally included 28 studies which met the eligibility criteria in the analysis. Most studies were single-centre and the majority were cross-sectional. Overall we included a total of 534 renal biopsies. Russell's viper bite was the most common cause related to AKI. Acute tubular necrosis was the most common finding followed by acute interstitial nephritis, acute cortical necrosis (ACN), and thrombotic microangiopathy (TMA). Vasculitis changes in vessels were rarely reported. Lesions such as ACN and TMA were associated with poor outcomes.

CONCLUSION

This analysis supports the notion that renal biopsies are important to guide prognosis and increase our knowledge about post-snake bite AKI pathophysiology.

Successful Management of Severe Unresponsive Snake Bite Envenomation Using Plasmapheresis and Corticosteroid at Egyptian National Environmental and Clinical Toxicology Research Center: A Case Report

Snakebite is a significant public health issue in which venom-induced consumption coagulopathy is a common and serious complication that results from the activation of the coagulation pathway by snake toxins. We report a male patient, 56 y old, who was thought to have been bitten by a snake on his left foot. He was transported to a nearby hospital where he received analgesics and 3 snake polyvalent antivenom vials, and then he was transported to our hospital after 12 h. He presented with 2 small puncture wounds, pain, blistering, and edema of the left foot. On the 2nd day, the patient developed gingival bleeding and hematuria. Laboratory investigations upon admission revealed prothrombin time (PT) of more than 3 min, prothrombin concentration (PC) of less than 2.5%, and an international normalized ratio (INR) of 23.43. Further investigation of urine showed more than 100 RBCs. Despite receiving 16 packs of plasma and 40 snake polyvalent antivenom vials manufactured by VACSERA over 3 days, hemoglobin concentration and platelet count decreased with the appearance of jaundice, lactate dehydrogenase was 520, and reticulocytes were 3.5%. PT was more than 300 s, and INR was still over range. Plasmapheresis and corticosteroids were provided, which improved the patient's general condition, PT, PC, and INR, and the patient was discharged after 6 days of hospital stay. This case report indicated that plasmapheresis and corticosteroids were clinically efficient approaches in the management of snake envenomation unresponsive to antivenom.

Urinary proteomics reveals biological processes related to acute kidney injury in Bothrops atrox envenomings

Acute kidney injury (AKI) is a critical systemic complication caused by Bothrops envenoming, a neglected health problem in the Brazilian Amazon. Understanding the underlying mechanisms leading to AKI is crucial for effectively mitigating the burden of this complication. This study aimed to characterize the urinary protein profile of Bothrops atrox snakebite victims who developed AKI. We analyzed three groups of samples collected on admission: healthy subjects (controls, n = 10), snakebite victims who developed AKI (AKI, n = 10), and those who did not evolve to AKI (No-AKI, n = 10). Using liquid-chromatography tandem mass spectrometry, we identified and quantified (label-free) 1190 proteins. A panel of 65 proteins was identified exclusively in the urine of snakebite victims, with 32 exclusives to the AKI condition. Proteins more abundant or exclusive in AKI's urine were associated with acute phase response, endopeptidase inhibition, complement cascade, and inflammation. Notable proteins include serotransferrin, SERPINA-1, alpha-1B-glycoprotein, and NHL repeat-containing protein 3. Furthermore, evaluating previously reported biomarkers candidates for AKI and renal injury, we found retinol-binding protein, beta-2-microglobulin, cystatin-C, and hepcidin to be significant in cases of AKI induced by Bothrops envenoming. This work sheds light on physiological disturbances caused by Bothrops envenoming, highlighting potential biological processes contributing to AKI. Such insights may aid in better understanding and managing this life-threatening complication.

A Pilot Study Testing the Novel Use of a Snake Bite Compression Device for Field Hemostasis and Wound Repair in an Animal Model

INTRODUCTION

A commercially available snake bite device was pilot tested for novel use as a method of hemostasis and wound repair at a noncompressible site in a live swine model. The device is light, is plastic, uses a hook-and-loop strap attachment, and is easily deployed. The device could offer a method for the field repair of an actively bleeding laceration at a noncompressible site in an austere environment.

MATERIALS AND METHODS

This was an interventional, prospective, controlled study in a large animal model. The study was approved by the Rhode Island Hospital Institutional Review Board (IRB) and the Animal Welfare Committee/Institutional Animal Care and Use Committee and the Lifespan Research Conflict of Interest Committee. Each animal acted as its own control. Blood loss was measured and compared between repairs of standardized incisions with and without the device's application. The lacerations were sutured closed. Two proceduralists alternated tasks of wound repair versus blood collection. Blood loss was measured by using gauze sponges to capture the blood during a 30-second free-bleeding period and during the repair itself. Using a one sample t-test (the expected difference in blood loss between the two incision repair methods = 0 if the null hypothesis were true), we calculated the mean difference in the deltas between the repair methods.

RESULTS

The mean delta difference was 3.1 g (SE ± 0.97). The t-test demonstrated that there was a significantly greater blood loss during the standard repair method, t(9) = 3.11, P < 0.01 than during the repair with the device in place (see Fig. 2). A statistical power analysis conducted showed that with a sample size of 10 animals, there was sufficient statistical power to detect this significant effect (β = 0.82, α < 0.05, one-tailed).

CONCLUSIONS

There was statistically significantly less blood loss during the repairs with the device's application. This feasibility experiment demonstrates that a commercially available snakebite device may be useful for hemostasis during laceration repair at anatomic sites not amenable to application of tourniquets or compressive dressings. Strengths of the study include the prospective controlled design, including the use of each animal as its own control; alternating proceduralists to account for any variability in suturing efficiency; and the statistical significance of the results despite the small number of subjects. One weakness is that the time required for each repair was not measured. The device's portability and reusability suggest applicability in austere medical environments. Future studies could include timing the repairs, using a skin stapler or wound adhesive instead of sutures, applying a hemostatic agent before the repair, and sequentially applying the device to wounds longer than the device.

Optimizing survival in Russell's viper bite cases in low-resource setting: two case reports

INTRODUCTION

Snakebite envenomation poses a significant health risk, particularly in low-resource settings where access to proper treatment is limited.

CASE PRESENTATION

This study reports two cases of Russell's viper bites in rural Bangladesh, involving 48 and 35-year-old Bangladesh males, respectively, and highlights the difficulties in providing adequate medical care and in treating any complications that may arise. Both cases involved delayed access to healthcare, initial visit to traditional healers, and the development of severe complications such as coagulopathy, renal failure. After the intervention both cases survived which is scarce in low resource settings.

CONCLUSION

The cases underscore the importance of early recognition, appropriate management, and improved healthcare infrastructure to optimize survival outcomes in snakebite cases in resource-limited settings. These cases will contribute valuable insights to the field of snakebite management and provide guidance for improving survival rates and outcomes among snakebite victims in Bangladesh.

Thromboembolic events following a pit viper bite from Protobothrops mucrosquamatus (Taiwan Habu): A report of two cases

Protobothrops mucrosquamatus, also known as the Taiwan Habu, is a venomous snake prevalent in Taiwan. It is accountable for most snakebites in the region. The toxin of the Taiwan Habu has significant hemorrhagic potential. However, patients bitten by this snake often suffer more local injuries than systemic ones. This report presents two cases of individuals bitten by the Taiwan Habu who subsequently experienced thromboembolism. In the first case, an 88-year-old male, bitten on his fourth toe, suffered a cerebral infarction 32 hours post-bite. In the second case, an 82-year-old female, bitten on her ankle, experienced cardiac arrest 19 hours later. Both patients promptly received antivenom and showed no signs of coagulopathy either before or after the snakebite. However, elevated coagulation factor VIII levels were observed in the first case. Our aim is to understand the mechanism behind these thromboembolic events. This report emphasizes the unusually high level of coagulation factor VIIIa and highlights the need for further investigation into the mechanisms involved. Consequently, physicians should assess the risk of thromboembolic events in snakebite patients by evaluating coagulation factors during treatment.

Photobiomodulation Therapy to Treat Snakebites Caused by Bothrops atrox: A Randomized Clinical Trial

Importance

Bothrops venom acts almost immediately at the bite site and causes tissue damage.

Objective

To investigate the feasibility and explore the safety and efficacy of low-level laser therapy (LLLT) in reducing the local manifestations of B atrox envenomations.

Design, Setting, and Participants

This was a double-blind randomized clinical trial conducted at Fundação de Medicina Tropical Doutor Heitor Vieira Dourado, in Manaus, Brazil. A total of 60 adult participants were included from November 2020 to March 2022, with 30 in each group. Baseline characteristics on admission were similarly distributed between groups. Data analysis was performed from August to December 2022.

Intervention

The intervention group received LLLT combined with regular antivenom treatment. The laser used was a gallium arsenide laser with 4 infrared laser emitters and 4 red laser emitters, 4 J/cm2 for 40 seconds at each application point.

Main Outcomes and Measures

Feasibility was assessed by eligibility, recruitment, and retention rates; protocol fidelity; and patients' acceptability. The primary efficacy outcome of this study was myolysis estimated by the value of creatine kinase (U/L) on the third day of follow-up. Secondary efficacy outcomes were (1) pain intensity, (2) circumference measurement ratio, (3) extent of edema, (4) difference between the bite site temperature and that of the contralateral limb, (5) need for the use of analgesics, (6) frequency of secondary infections, and (7) necrosis. These outcomes were measured 48 hours after admission. Disability assessment was carried out from 4 to 6 months after patients' discharge. P values for outcomes were adjusted with Bonferroni correction.

Results

A total of 60 patients (mean [SD] age, 43.2 [15.3] years; 8 female individuals [13%] and 52 male individuals [87%]) were included. The study was feasible, and patient retention and acceptability were high. Creatine kinase was significantly lower in the LLLT group (mean [SD], 163.7 [160.0] U/L) 48 hours after admission in relation to the comparator (412.4 [441.3] U/L) (P = .03). Mean (SD) pain intensity (2.9 [2.7] vs 5.0 [2.4]; P = .004), circumference measurement ratio (6.6% [6.6%] vs 17.1% [11.6%]; P < .001), and edema extent (25.8 [15.0] vs 40.1 [22.7] cm; P = .002) were significantly lower in the LLLT group in relation to the comparator. No difference was observed between the groups regarding the mean difference between the bite site temperature and the contralateral limb. Secondary infections, necrosis, disability outcomes, and the frequency of need for analgesics were similar in both groups. No adverse event was observed.

Conclusions and Relevance

The data from this randomized clinical trial suggest that the use of LLLT was feasible and safe in a hospital setting and effective in reducing muscle damage and the local inflammatory process caused by B atrox envenomations.

Trial Registration

Brazilian Registry of Clinical Trials Identifier: RBR-4qw4vf.

Unveiling the secrets of snakes: Analysis of environmental, socioeconomic, and spatial factors associated with snakebite risk in Paraná, Southern Brazil

The state of Paraná is home to three out of the five medically significant snake genera in Brazil and lacks of snakebite epidemiology studies. This study aimed to ascertain the spatial, environmental, and socioeconomic factors associated with snakebite risk by analyzing notification data of cases in the state of Paraná. Notification and socioeconomic data were gathered from the online platforms of the National System of Notifiable Diseases (SINAN) and the Brazilian Institute of Geography and Statistics (IBGE). Land cover and land use maps were obtained from the Mapbiomas platform in raster format and subsequently converted into vectors using QGis software. The proportions of land use and land cover in square kilometers (km2) were then calculated. All acquired data were tabulated using Microsoft Excel 365 software. For spatial analysis, GeoDa software version 1.20 was utilized to calculate the Global and Local Moran indices, assessing spatial correlations. Between 2007 and 2021, 12,877 notifications were recorded, with an average incidence of 8.22/100,000 inhabitants in the state, 8166 (63.41%) caused by Bothrops, 1534 (11.91%) caused by Crotalus, 56 (0.43%) caused by Micrurus. 1703 (13.22%) caused by non-venomous snake species, and the remaining cases did not have the identified causative species. The incidents caused by Bothrops and Crotalus showed different distribution patterns. Spatial analysis revealed that key factors contributing to snakebite risk included the presence of native forests, mangroves, apicuns, and monospecific planted forests. The population group at the highest risk comprised rural residents and workers. Furthermore, the absence of basic sanitation and proper garbage collection and disposal exhibited positive correlations with snakebites. Conversely, intensive farming practices with substantial mechanization and pastures demonstrated negative spatial correlations. This study has enabled the identification of the primary factors associated with snakebite risk, facilitating more targeted efforts to prevent snakebite accidents among vulnerable populations.

Hemoperitoneum after a Bothrops snakebite: Case report

Snakebites are frequent in tropical countries. Brazil has an average of 27,000 cases per year, with a fatality rate of 0.5%, and the Bothrops genus is the most common causative agent, accounting for about 70-90% of the accidents. This report describes a case of human envenomation by a juvenile Bothrops jararaca snake in São Paulo, Brazil, in a 71 years-old man, previously healthy. He presented a life-threatening envenomation, which developed to severe hypotension, acute kidney injury and extensive peritoneal hemorrhage. The hemoperitoneum was diagnosed due to persistent hypotension associated with anemia, pain and gastrointestinal complaints. Abdominal Computed Tomography scans showed a moderate to large amount of presumable hematic material inside the abdominal cavity, predominantly in the perihepatic and perisplenic spaces. The intra-abdominal hemorrhage was not surgically addressed, and the patient was discharged 5 days after hospitalization, with the progressive absorption of the hemoperitoneum. Systemic bleeding is one of the complications and main causes of death in Bothrops envenomations. Acute peritoneal hemorrhage is one of these serious complications that must be carefully addressed since its management must take into account the risk of bleeding caused by toxins that affect hemostasis. The case described highlights the importance of early diagnosis and adequate management of this potentially fatal complication in snakebites.

Agonists of melatonin receptors strongly promote the functional recovery from the neuroparalysis induced by neurotoxic snakes

Snake envenoming is a major, but neglected, tropical disease. Among venomous snakes, those inducing neurotoxicity such as kraits (Bungarus genus) cause a potentially lethal peripheral neuroparalysis with respiratory deficit in a large number of people each year. In order to prevent the development of a deadly respiratory paralysis, hospitalization with pulmonary ventilation and use of antivenoms are the primary therapies currently employed. However, hospitals are frequently out of reach for envenomated patients and there is a general consensus that additional, non-expensive treatments, deliverable even long after the snake bite, are needed. Traumatic or toxic degenerations of peripheral motor neurons cause a neuroparalysis that activates a pro-regenerative intercellular signaling program taking place at the neuromuscular junction (NMJ). We recently reported that the intercellular signaling axis melatonin-melatonin receptor 1 (MT1) plays a major role in the recovery of function of the NMJs after degeneration of motor axon terminals caused by massive Ca2+ influx. Here we show that the small chemical MT1 agonists: Ramelteon and Agomelatine, already licensed for the treatment of insomnia and depression, respectively, are strong promoters of the neuroregeneration after paralysis induced by krait venoms in mice, which is also Ca2+ mediated. The venom from a Bungarus species representative of the large class of neurotoxic snakes (including taipans, coral snakes, some Alpine vipers in addition to other kraits) was chosen. The functional recovery of the NMJ was demonstrated using electrophysiological, imaging and lung ventilation detection methods. According to the present results, we propose that Ramelteon and Agomelatine should be tested in human patients bitten by neurotoxic snakes acting presynaptically to promote their recovery of health. Noticeably, these drugs are commercially available, safe, non-expensive, have a long bench life and can be administered long after a snakebite even in places far away from health facilities.

Serpent strikes, sapien sways: A rare case of bilateral cerebellar infarct following viper bite

Ischemic stroke following snake bite is rare. We report a posterior circulation infarct involving bilateral cerebellum and occipital lobe following Russell's viper bite in a previously healthy individual. A 50 years old healthy individual, soon after being bitten by the Russel viper on the left foot he developed pain and swelling followed by drooping of eyelids, slurring of speech and giddiness with multiple episodes of vomiting. The patient was administered ASV as well as neostigmine and atropine injections. Following this, the neurological manifestations resolved except dysarthria. CT brain study done was normal. On day 2 of hospitalization, he developed left cerebellar signs (positive finger nose finger test, rebound phenomenon, dysdiadochokinesia, a positive heel shin test). Subsequently, an MRI with MR angiogram was done which showed acute infarcts in bilateral cerebellar hemispheres, with the left superior cerebellar peduncle showing restricted diffusion and low ADC values. Ischemic infarction following viper envenomation has been described by only few authors. In majority of the cases reported, ischemic infarction involved the anterior circulation. The possible mechanisms of infarction in this scenario are discussed. Patient was treated with anti-snake venom and showed a good recovery. Early imaging and early treatment with anti-snake venom is important for a favourable outcome.

Case Report: Snake Venom Ophthalmia Caused by Cobra Exposure: A Report of 26 Cases

We report 26 cases of eye injuries resulting from cobra venom sprayed by Naja atra. This accounts for 14.5% of patients (26/173) treated for cobra injuries who presented to the emergency department of a snakebite treatment center in Guangzhou, South China. Pain, blurred vision, lacrimation, photophobia, and foreign body sensation were the most common symptoms, found in 24 patients. Ophthalmic examination revealed eyelid swelling and conjunctival congestion. Eye slit lamp examination showed obvious punctate corneal epithelial defects in four patients. Five patients received an intravenous infusion of antivenom. All patients' eyes were rinsed completely with normal saline after their arrival at the hospital. Prophylactic topical antibiotics were given to all patients. All eyes were cured without long-term sequelae.

A Case of Cobra Bite in a Term Pregnant Woman: The Obstetric and Wound Management Challenges

Snake envenomation is a rare incident during pregnancy and potentially challenging to manage. Snakebites in pregnancy may lead to several complications such as teratogenicity, miscarriage, antepartum hemorrhage, and even intrauterine fetal death. Here, we report a case of a pregnant woman who presented to our emergency department with signs of systemic envenomation following an Indian cobra bite on her foot, highlighting the key obstetric and wound management challenges. She complained of severe pain at the site of the bite and progressive swelling, abdominal pain, and multiple episodes of vomiting, which started 45 min after the bite. She received 10 vials of polyvalent antivenom from a primary hospital and was then referred to our center. The patient underwent emergency cesarean section and later fasciotomy with free-flap reconstruction at the bitten site due to local tissue necrosis. The case was successfully managed by a multidisciplinary team consisting of an emergency physician, obstetrician, and plastic surgeon, saving 2 lives and the limb of the patient.

ADDovenom: Thermostable Protein-Based ADDomer Nanoparticles as New Therapeutics for Snakebite Envenoming

Snakebite envenoming can be a life-threatening medical emergency that requires prompt medical intervention to neutralise the effects of venom toxins. Each year up to 138,000 people die from snakebites and threefold more victims suffer life-altering disabilities. The current treatment of snakebite relies solely on antivenom-polyclonal antibodies isolated from the plasma of hyperimmunised animals-which is associated with numerous deficiencies. The ADDovenom project seeks to deliver a novel snakebite therapy, through the use of an innovative protein-based scaffold as a next-generation antivenom. The ADDomer is a megadalton-sized, thermostable synthetic nanoparticle derived from the adenovirus penton base protein; it has 60 high-avidity binding sites to neutralise venom toxins. Here, we outline our experimental strategies to achieve this goal using state-of-the-art protein engineering, expression technology and mass spectrometry, as well as in vitro and in vivo venom neutralisation assays. We anticipate that the approaches described here will produce antivenom with unparalleled efficacy, safety and affordability.

Early-Onset Respiratory Muscle Paralysis in Crotalic Envenomation: A Case Study

Crotalic envenomation is responsible for approximately 8%-13% of ophidism cases in Brazil, yet it is associated with the highest mortality among snakes. We describe the case of a patient bitten by a rattlesnake who developed ventilatory muscle paralysis within hours after envenomation. While diaphragmatic paralysis is a rare late neurotoxic event following crotalic envenomation, in this case, paralysis occurred early but was rapidly reversed after antivenom administration. This report discusses potential contributing factors based on a comprehensive literature review.

Bothrops venom-induced hemostasis disorders in the rat: Between Scylla and Charybdis

Hemostasis impairment represents the most threatening consequence of Viperidae envenoming, notably with Bothrops genus. In the French departments of America, B. atrox envenomation in French Guiana may lead to bleeding while B. lanceolatus envenomation in Martinique to thrombosis. Bleeding related to B. atrox envenomation is attributed to vascular damage mediated by venom metalloproteinases and blood uncoagulable state resulting from thrombocytopenia and consumptive coagulopathy. Thrombosis related to B. lanceolatus envenomation are poorly understood. We aimed to compare the effects of B. atrox and B. lanceolatus venoms in the rat to identify the determinants of the hemorrhagic versus thrombotic complications. Viscoelastometry (ROTEM), platelet count, plasma fibrinogen, thrombin generation assay, fibrinography, endothelial (von Willebrand factor, ADAMTS13 activity, ICAM-1, and soluble E-selectin), and inflammatory biomarkers (IL-1β, IL-6, TNF-α, MCP-1, and PAI-1) were determined in blood samples obtained at H3, H6, and H24 after the subcutaneous venom versus saline injection. In comparison to the control, initial fibrinogen consumption was observed with the two venoms while thrombocytopenia and reduction in the clot amplitude only with B. atrox venom. Moreover, we showed an increase in thrombin generation at H3 with the two venoms, an increase in fibrin generation accompanied with hyperfibrinogenemia at H24 and an increase in inflammatory biomarkers with B. lanceolatus venom. No endothelial damage was found with the two venoms. To conclude, our data support two-sided hemostasis complications in Bothrops envenoming with an initial risk of hemorrhage related to platelet consumption and hypocoagulability followed by an increased risk of thrombosis promoted by the activated inflammatory response and rapid-onset fibrinogen restoration.

Real life condition evaluation of Inoserp PAN-AFRICA antivenom effectiveness in Cameroon

BACKGROUND

Snakebites is a serious public health issue but remains a neglected tropical disease. Data on antivenom effectiveness are urgently needed in Africa. We assessed effectiveness of Inoserp PAN-AFRICA (IPA), the recommended antivenom available in Cameroon.

METHODOLOGY/PRINCIPAL FINDINGS

We enrolled 447 patients presenting with snakebite in 14 health facilities across Cameroon. At presentation, cytotoxicity, coagulation troubles and neurotoxicity were graded. We administered two to four vials of antivenom to patients based on hemotoxic or neurotoxic signs. We renewed antivenom administration to patients with persistence of bleedings or neurotoxicity 2 hours after each injection. We defined early improvement as a reduction of the grade of envenomation symptoms 2 hours after first injection. Medium-term effectiveness was investigated looking at disappearance of symptoms during hospitalization. After hospital discharge, a home visit was planned to assess long-term outcomes. Between October 2019 and May 2021, we enrolled 447 (93.7%), including 72% from the savannah regions. The median [IQR] age was 25 [14-40]. Envenomation was diagnosed in 369 (82.6%) participants. The antivenom was administered to 356 patients (96.5%) of whom 256 (71.9%) received one administration. Among these patients, cytotoxic symptoms were observed in 336 (94.4%) participants, coagulation disorders in 234 (65.7%) participants and neurotoxicity in 23 (6.5%) participants. Two hours after the first administration of antivenom, we observed a decrease in coagulation disorders or neurotoxicity in 75.2% and 39.1% of patients, respectively. Complete cessation of bleedings and neurotoxicity occurred in 96% and 93% of patients within 24 hours, respectively. Sequelae have been observed in 9 (3%) patients at the home visit 15 days after hospital admission and 11 (3%) died including one before antivenom injection.

CONCLUSIONS/SIGNIFICANCE

We confirmed good effectiveness of the IPA and highlighted the rapid improvement in bleeding or neurotoxicity after the first administration. Sequential administrations of low doses of antivenom, rigorously assessed at short intervals for an eventual renewal, can preserve patient safety and save antivenom.

TRIAL REGISTRATION

NCT03326492.

Hyponatremia due to adrenal insufficiency after a Mamushi bite: a case report

BACKGROUND

Mamushi bites are the most common venomous snake bites in Japan, with known complications including rhabdomyolysis and acute kidney injury; however, adrenal insufficiency as a result of snake bites has not been previously reported. We report a case of empty sella with transient adrenal insufficiency during hospitalization for a Mamushi bite.

CASE PRESENTATION

An 84-year-old man was admitted to our hospital with a Mamushi bite on the right fifth finger. Serum sodium (Na) level remained in the normal range. On the ninth day of admission, he developed hyponatremia, with a serum Na level of 114 mEq/L and serum cortisol level of 4.0 μg/dL (reference value 4.5-21.1 μg/dL). His serum Na level was restored within the normal range after administration of corticosteroids with 3% NaCl solution. Both rapid adrenocorticotrophin and corticotropin-releasing hormone loading tests showed low cortisol response. Based on the results of the hormone loading tests, a diagnosis of pituitary adrenal insufficiency was made. Contrast-enhanced pituitary magnetic resonance imaging (MRI) showed primary empty sella. After discontinuation of corticosteroids, the hyponatremia did not recur, and the patient was discharged on the 24th day of hospitalization. After discharge, the patient visited an outpatient clinic, but hyponatremia recurrence was not observed.

CONCLUSIONS

This is the first report of hyponatremia due to pituitary adrenal insufficiency during hospitalization for a Mamushi bite in a patient with empty sella. When hyponatremia occurs during hospitalization for a Mamushi bite, cortisol measurement, hormone loading test, and head MRI should be performed to search for pituitary lesions because of the possibility of adrenal insufficiency caused by snake venom.

Cold Finger: Raynaud Phenomenon Following Snakebite Envenoming by Nikolsky's Viper (Vipera berus nikolskii)

A field biologist was bitten by a female Nikolsky's viper (Vipera berus nikolskii) in Kharkiv Oblast, Ukraine. Two months later, the patient began to experience cold-induced vasospasm of the affected digit diagnosed as acquired Raynaud phenomenon. The patient had more than 30 occurrences during the single winter following the bite, but the signs and symptoms of Raynaud phenomenon disappeared with the end of winter. This report describes the case and puts it into context with the literature on the topic of toxin-induced peripheral vasospastic disorders and their potential importance in snakebite envenoming.

Pediatric Rattlesnake Envenomations Treated With Crotalidae Equine Immune F(Ab') 2 Antivenom : A 3-Year Retrospective Observational Analysis

OBJECTIVES

Rattlesnake envenomations are uncommon, and the majority occur in adults. Although Crotalidae equine immune F(ab') 2 antivenom (F(ab') 2 AV; trade name ANAVIP) was introduced in 2018, no pediatric specific studies of F(ab') 2 AV have been reported to date. The objective of this study was to evaluate the clinical performance and adverse effects of F(ab') 2 AV in children.

METHODS

A single-center, retrospective chart review was performed on patients with rattlesnake envenomation presenting to a children's hospital between October 2018 and August 2022. Inclusion criteria were age younger than 18 years and F(ab') 2 AV use. Exclusion criteria were other antivenom use at any time and presentation beyond 24 hours postenvenomation.Demographic characteristics, hemoglobin, platelet count, fibrinogen, international normalized ratio, number of F(ab') 2 AV vials used, infusion-related complications, and clinical outcomes were collected.

RESULTS

Twenty-six patients, 19 males and 7 females, with a mean age of 7.7 years (0.67 to 16 years) met inclusion criteria. Fourteen (54%) were treated with only the initial 10 vial F(ab') 2 AV doses. Twelve patients were given additional doses with a median additional vials of 10 (4-34 vials; interquartile range, 8.75-12 vials). The median total vials given for all patients was 10 (10-44 vials; interquartile range, 10-20 vials).Two patients developed acute infusion reactions. Both were treated by slowing the infusion rate and with medications (diphenhydramine, corticosteroids). No delayed reactions were noted. No patients required blood products or surgical interventions.After discharge, no complications, recurrent symptoms, return visits, or readmissions were reported. Follow-up by chart review or phone was obtained for 18 patients, and no postdischarge complications were noted. Seven patients had postdischarge hematologic laboratory evaluations and all were normal.

CONCLUSIONS

Although limited by small sample size and postdischarge follow-up, F(ab') 2 AV was well tolerated in our series of pediatric patients, consistent with prior studies of all age groups.

Risk factors and outcome of acute kidney injury in children with snake envenomation

Our study evaluates the risk factors of acute kidney injury (AKI) in children with snake envenomation. Out of 145 cases, 54 (37%) developed AKI. Unsurprisingly, the mortality increased with oliguria and higher levels of creatinine. Bleeding manifestations were also more common among the AKI group.

Compartment Syndrome after Crotalid Envenomation in the United States: A Review of the North American Snakebite Registry from 2013 to 2021 on Behalf of the ToxIC Snakebite Study Group

INTRODUCTION

Compartment syndrome (CS) is a rare but serious complication after crotalid envenomation in the United States. Few data are available regarding the epidemiology and management of these cases. Significant controversy and misunderstanding over best practices, including measurement of compartment pressures and use of fasciotomy, exist for this syndrome. This study aims to describe presentation and management of suspected CS cases after native snakebite reported to the North American Snakebite Registry (NASBR).

METHODS

This is an analysis of snakebite cases reported to the Toxicology Investigators Consortium NASBR between January 1, 2013 and December 31, 2021. Cases of native snakebite with documented concern for CS were included.

RESULTS

Over an 8-y period, 22 cases of suspected CS were identified, representing 1% of all cases reported to the NASBR. Fasciotomies were performed in 41% (n=9) of these cases, most commonly to the upper extremity (67%, n=6). In cases of suspected CS, intracompartmental pressures (ICPs) were rarely measured (23%, n=5) and fasciotomies were performed without measurement of ICPs frequently (56%, n=5). In 1 case, ICPs were measured and found to be low (8 mm Hg) and fasciotomy was avoided.

CONCLUSIONS

Measurement of compartment pressures in cases of suspected CS was uncommon in cases reported to the NASBR. Fasciotomy was commonly performed without measurement of compartment pressures.

Long-term health manifestations of hump-nosed pit viper (Genus: Hypnale) bites

INTRODUCTION

The hump-nosed pit viper (Genus: Hypnale) is a highly medically significant snake in Sri Lanka, responsible for the majority of venomous snakebites (22-77%). They are found throughout Sri Lanka and the Western Ghats region of India. The venom can lead to two types of effects: acute and long-term. Acutely, bites often result in local symptoms, with less common systemic effects such as acute kidney injury, venom-induced consumption coagulopathy, and thrombotic microangiopathy.

METHODS

We conducted a prospective observational study at Teaching Hospital Ratnapura, Sri Lanka, spanning six years, starting in June 2015. Patients bitten by hump-nosed pit vipers were followed up for two years, with assessments every three months to identify long-term effects. Data was gathered through interviewer-administered questionnaires.

RESULTS

Out of 728 patients bitten by hump-nosed pit vipers, 22 (3%) were lost to follow-up. Forty-four (6.2%) experienced long-term effects, including chronic kidney disease (24; 3.4%), chronic wounds (five; 0.7%), amputations (five; 0.7%), fasciotomy-related wounds (four; 0.6%), and psychological illnesses (four; 0.6%). There were nine (1.3%) deaths in this group. Among those with chronic effects, 27 (61%) were males, and 17 (39%) were females, with ages ranging from 29 to 82 years (mean 57.6 years). The time it took to diagnose acute kidney injury from the snakebite was 18 h (interquartile range: 15-23.5 h), while the time to diagnose chronic kidney disease was 69 days (interquartile range: 64-74.75 days). In these patients, the estimated glomerular filtration rate was 29.3 mL/min/1.73 m2 (interquartile range: 14-50.75 mL/min/1.73 m2). Among the patients who did not develop long-term complications (662; 91%) 660 (90.7%) experienced local effects, and 82 (11.3%) developed systemic manifestations, including acute kidney injury in 60 (8%) and coagulopathy in 35 (5%).

CONCLUSION

Following hump-nosed pit viper bites, a subset of patients may experience long-term health complications, including chronic kidney disease, chronic ulcers, amputations, fasciotomy-related wounds, and psychological illnesses, with chronic kidney disease being the most frequently observed among these manifestations.

Delayed Compression Paralysis Following an Iliopsoas Hematoma 30 Days After Saw-Scaled Viper (Echis carinatus sochureki) Envenoming: A Case Report

Snakebite envenoming is a neglected tropical disease disproportionately affecting the rural and marginalized population in low-middle-income countries. The saw-scaled viper (Echis carinatus) is a clinically important snake that causes serious morbidity and mortality in the Indian subcontinent. Even though it is within the so-called big-four snakes against which polyvalent antivenom is available throughout India, reports of antivenom ineffectiveness are emerging in saw-scaled viper envenoming, especially around Jodhpur, Rajasthan, India. This case report highlights a patient with saw-scaled viper envenoming with an ineffective antivenom response complicated by acute kidney injury as well as local and systemic bleeding complications, which subsequently resulted in a pelvic hematoma that compressed the lumbosacral nerves, causing lower-limb weakness and sensory deficits. He was successfully managed with hematoma aspiration and supportive care. This case brings into focus the challenges of managing saw-scaled viper envenoming in this region with antivenom ineffectiveness, resulting in delayed and significant coagulopathy and its complications leading to prolonged hospital stay and morbidity. Our report spotlights less emphasized aspects of long-term morbidity in snakebite survivors, such as loss of working days and productivity. We also highlight the need for an organized system of long-term follow-up of snakebite survivors to screen for possible complications and manage them early.

Snake Envenomation Simulating ST Elevation Myocardial Infarction

Envenomation syndromes following snakebites can include tissue reaction, coagulopathy, nephrotoxicity, and neurotoxicity. Cardiotoxicity is rare but usually presents with dysrhythmias. Myocardial infarction after envenomation has rarely been reported. We discuss a case of snake bite simulating ST-elevation myocardial infarction (STEMI). Our patient is a 49-year-old male who sustained a snake bite in his left hand. Patient had hemodynamic collapse requiring increasing pressor support; EKG and troponin results confirmed STEMI. Cardiac catheterization did not demonstrate any thrombosis, rather severe cardiomyopathy with left ventricular ejection fraction 20-25%. Even though our patient did not require any coronary intervention, an angiogram was warranted given the clinical presentation. Our case demonstrates severe cardiotoxicity following snake bite. Further research is warranted to study the mechanism behind such phenomena.

Thromboelastography Use to Guide Resuscitation and Antivenom Administration after Gaboon Viper Bite

The Gaboon viper (Bitis gabonica) is an exotic snake native to sub-Saharan Africa. Gaboon viper venom is an extremely toxic hemotoxin, causing severe coagulopathy and local tissue necrosis. These are not aggressive snakes and therefore bites involving humans are rare and there is not a substantial amount of literature documenting how to manage these injuries and resultant coagulopathies. We report a 29-year-old male presenting 3 hours after a Gaboon viper envenomation resulting in coagulopathy requiring massive resuscitation and multiple doses of antivenom. The patient received various blood products based on thromboelastography (TEG) and also underwent early continuous renal replacement therapy (CRRT) to assist in correction of severe acidosis and acute renal failure. The combination of TEG to guide resuscitation, administration of antivenom, and early implementation of CRRT allowed our team to correct venom-induced consumptive coagulopathy and ultimately allow the patient to survive following this extremely deadly Gaboon viper envenomation.

Intramuscular Bleeding and Formation of Microthrombi during Skeletal Muscle Damage Caused by a Snake Venom Metalloprotease and a Cardiotoxin

The interactions between specific snake venom toxins and muscle constituents are the major cause of severe muscle damage that often result in amputations and subsequent socioeconomic ramifications for snakebite victims and/or their families. Therefore, improving our understanding of venom-induced muscle damage and determining the underlying mechanisms of muscle degeneration/regeneration following snakebites is critical to developing better strategies to tackle this issue. Here, we analysed intramuscular bleeding and thrombosis in muscle injuries induced by two different snake venom toxins (CAMP-Crotalus atrox metalloprotease (a PIII metalloprotease from the venom of this snake) and a three-finger toxin (CTX, a cardiotoxin from the venom of Naja pallida)). Classically, these toxins represent diverse scenarios characterised by persistent muscle damage (CAMP) and successful regeneration (CTX) following acute damage, as normally observed in envenomation by most vipers and some elapid snakes of Asian, Australasian, and African origin, respectively. Our immunohistochemical analysis confirmed that both CAMP and CTX induced extensive muscle destruction on day 5, although the effects of CTX were reversed over time. We identified the presence of fibrinogen and P-selectin exposure inside the damaged muscle sections, suggesting signs of bleeding and the formation of platelet aggregates/microthrombi in tissues, respectively. Intriguingly, CAMP causes integrin shedding but does not affect any blood clotting parameters, whereas CTX significantly extends the clotting time and has no impact on integrin shedding. The rates of fibrinogen clearance and reduction in microthrombi were greater in CTX-treated muscle compared to CAMP-treated muscle. Together, these findings reveal novel aspects of venom-induced muscle damage and highlight the relevance of haemostatic events such as bleeding and thrombosis for muscle regeneration and provide useful mechanistic insights for developing better therapeutic interventions.

Inflammatory Profile Associated with Secondary Infection from Bothrops atrox Snakebites in the Brazilian Amazon

Bothrops snakebite envenomation (SBE) is consider an important health problem in Brazil, where Bothrops atrox is mainly responsible in the Brazilian Amazon. Local effects represent a relevant clinical issue, in which inflammatory signs and symptoms in the bite site represent a potential risk for short and long-term disabilities. Among local complications, secondary infections (SIs) are a common clinical finding during Bothrops atrox SBE and are described by the appearance of signs such as abscess, cellulitis or necrotizing fasciitis in the affected site. However, the influence of SI in the local events is still poorly understood. Therefore, the present study describes for the first time the impact of SBE wound infection on local manifestations and inflammatory response from patients of Bothrops atrox SBE in the Brazilian Amazon. This was an observational study carried out at the Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus (Brazil), involving victims of Bothrops SBE. Clinical and laboratorial data were collected along with blood samples for the quantification of circulating cytokines and chemokines before antivenom administrations (T0) and 24 h (T1), 48 h (T2), 72 h (T3) and 7 days after (T4). From the 94 patients included in this study, 42 presented SI (44.7%) and 52 were without SI (NSI, 55.3%). Patients classified as moderate envenoming presented an increased risk of developing SI (OR = 2.69; CI 95% = 1.08-6.66, p = 0.033), while patients with bites in hands showed a lower risk (OR = 0.20; CI 95% = 0.04-0.96, p = 0.045). During follow-up, SI patients presented a worsening of local temperature along with a sustained profile of edema and pain, while NSI patients showed a tendency to restore and were highlighted in patients where SI was diagnosed at T2. As for laboratorial parameters, leukocytes, erythrocyte sedimentation ratio, fibrinogen and C-reactive protein were found increased in patients with SI and more frequently in patients diagnosed with SI at T3. Higher levels of circulating IL-2, IL-10, IL-6, TNF, INF-γ and CXCL-10 were observed in SI patients along with marked correlations between these mediators and IL-4 and IL-17, showing a plurality in the profile with a mix of Th1/Th2/Th17 response. The present study reports for the first time the synergistic effects of local infection and envenoming on the inflammatory response represented by local manifestations, which reflected on laboratorial parameters and inflammatory mediators and thus help improve the clinical management of SI associated to Bothrops SBE.

Bothrops asper bite and post-traumatic stress disorder in Costa Rica: Report of two cases

Snakebite envenoming (SBE) is a public health problem of high impact worldwide. The psychiatric consequences of SBE have been poorly documented. Here we present in detail the phenomenology of two clinical cases of Bothrops asper snakebite post-traumatic stress disorder (SBPTSD) in Costa Rica. We suggest that there is a characteristic presentation of SBPTSD and hypothesize that main contributors to the development of this disorder are: the systemic inflammatory response, the repetition of events that put the patient's life at risk and the human innate fear of snakes. Protocols for the prevention, detection and treatment of PTSD in patients who suffer a SBE should be implemented, with at least one mental health care consultation during hospitalization and a 3-5 months follow-up after the discharge.

Namibian spitting cobra, Naja nigricincta nigricincta (Zebra snake): Antibiotic profile of bacteria cultured from the oral pharynx, venom and snakebite wounds

This was a cross-sectional study with the aim of characterising Naja nigricincta nigricincta's oral bacterial flora as well as accompanying sensitivities and resistance towards antibiotics. Naja nigricincta nigricincta (zebra snake) is a spitting cobra indigenous to Namibia. Nasopharyngeal and venom swabs for bacterial culture and antibiotic sensitivity were taken from 37 native zebra snakes originating from the Khomas region that were captured for removal and relocation. Enterococcus faecalis, Proteus spp., Morganella morganii and Pseudomonas spp. were the organisms most often cultured. The antibiotic sensitivity profiles of these organisms suggest ciprofloxacin or a third-generation cephalosporin plus gentamicin or piperacillin-tazobactam as prophylactic antibiotics in case of Naja nigricincta nigricincta bites.

Intravenous snake bite: A catastrophic snake envenomation

The rapid onset of life-threatening clinical manifestations in venomous snake bite could be due to an intravenous bite. This article seeks to review and consider the clinical implications, pathophysiology, and management of this rare route of snake envenomation broadly by venomous snakes which are little described in the available literature.

Treatment of a Snakebite Injury With Secondary Bacterial Infection: A Case Study

BACKGROUND

Pit viper snakebites are challenging as they often cause tissue injury and secondary bacterial infection that may impair full recovery of the affected limb. We describe the evolution of a snakebite injury with secondary infection and the use of specialized dressings to achieve tissue repair and complete closure of the wound.

CASE

Ms E., a 45-year-old woman, was bitten by a pit viper that began as a small lesion and progressed to necrosis, cellulitis, edema, and hyperemia of the perilesional skin, local inflammation, and infection. We implemented a combination of topical hydrogel therapy with calcium alginate and hydrofiber with 1.2% silver to promote autolytic debridement, combat local infection, and provide a moist wound environment. The wound required daily local treatment for 2 months due to extensive tissue damage, combined with the proteolytic action of the bothropic venom.

CONCLUSION

The care of wounds caused by snakebites is a challenge for the health care team due to tissue loss resulting from the action of the venom and secondary bacterial infection. Close follow-up with the use of systemic antibiotics and topical therapies proved effective in minimizing tissue loss in this case.

Exploring the Profile of Cell Populations and Soluble Immunological Mediators in Bothrops atrox Envenomations

Bothrops atrox envenomations are common in the Brazilian Amazon. The venom of B. atrox is highly inflammatory, which results in severe local complications, including the formation of blisters. Moreover, there is little information on the immune mechanisms associated with this condition. Thus, a longitudinal study was carried out to characterize the profile of the cell populations and soluble immunological mediators in the peripheral blood and blisters in B. atrox patients s according to their clinical manifestations (mild and severe). A similar response in both B. atrox patient groups (MILD and SEV) was observed, with an increase in inflammatory monocytes, NKT, and T and B cells, as well as CCL2, CCL5, CXCL9, CXCL10, IL-1β and IL-10, when compared with the group of healthy blood donors. After the administration of antivenom, the participation of patrolling monocytes and IL-10 in the MILD group was observed. In the SEV group, the participation of B cells was observed, with high levels of CCL2 and IL-6. In the blister exudate, a hyperinflammatory profile was observed. In conclusion, we revealed the involvement of cell populations and soluble mediators in the immune response to B. atrox envenomation at the local and peripheral level, which is related to the onset and extent of the inflammation/clinical manifestation.

The Effectiveness of Antibiotics in Managing Bacterial Infections on Bite Sites following Snakebite Envenomation

Snakebite envenomation (SBE) is a life-threatening medical emergency with a high mortality rate. Common secondary complications following SBE, such as wound infections, are significant due to their impact on worsening local tissue damage and causing systemic infection. Antivenoms are not effective to treat wound infections following SBE. Moreover, in several rural clinical settings, broad-spectrum antibiotics are often used without clear guidelines or based on limited laboratory data, resulting in undesirable side effects and exacerbated treatment costs. Therefore, robust antibiotic strategies should be developed to tackle this critical issue. Currently, there is limited information available on the bacterial profiles of SBE-induced infections and antibiotic susceptibility. Hence, it is essential to improve the knowledge of bacterial profiles and their antibiotic sensitivity in SBE victims to develop better treatment strategies. This study aimed to address this issue by examining the bacterial profiles of SBE victims with a specific focus on Russell's viper envenomation. The most frequently found bacteria in the bites of SBE victims were Staphylococcus aureus, Klebsiella sp., Escherichia coli, and Pseudomonas aeruginosa. Linezolid, clindamycin, colistin, meropenem, and amikacin were some of the most effective antibiotics for commonly grown bacteria in SBE victims. Similarly, ciprofloxacin, ampicillin, amoxiclave, cefixime, and tetracyclin were the least effective antibiotics for common bacteria found in the wound swabs of SBE victims. These data provide robust guidance for infection management following SBE and offer useful insights to aid in designing effective treatment protocols for SBE with serious wound infections in rural areas where laboratory facilities may not be readily available.

Epidemiology of secondary infection after snakebites in center-west Brazil

BACKGROUND

Snakebites represent a significant health problem in tropical countries, with an annual incidence of 2.7 million cases worldwide. The incidence of secondary infections after snake bites is also high and is usually caused by bacteria from the oral cavity of snakes. Morganella morganii has been identified as an important cause of infections and has been guiding antibiotic therapy in several regions of Brazil and the world.

METHODOLOGY/PRINCIPAL FINDINGS

We performed a retrospective cross-sectional evaluation of snakebites in hospitalized patients between January 2018 and November 2019 and selected those with secondary infection in their medical records. During the period, 326 cases of snakebites were treated, and 155 (47.5%) of them eventually had secondary infections. However, only seven patients underwent culture of soft tissue fragments, in which three cases were negative culture results, while Aeromonas hydrophila was identified in four cases. Of these, 75% were resistant to ampicillin/sulbactam, 50% had intermediate sensitivity to imipenem, and 25% had intermediate sensitivity to piperacillin/tazobactam. Trimethoprim/sulfamethoxazole (TMP-SMX) was not tested on any strain. Of the 155 cases that progressed to secondary infections, 48.4% (75) were empirically treated with amoxicillin/clavulanate, 41.9% (65) with TMP-SMX, and 32 (22%) of these 144 cases required a change to a second regimen, and 10 of these 32 patients required a third therapeutic regimen.

CONCLUSION

Wild animals act as reservoirs of resistant bacteria because their oral cavity favors biofilm formation, which explains the finding of A. hydrophila with a reduced sensitivity profile in this study. This fact is essential for the appropriate choice of empirical antibiotic therapy.

Epidemiological and clinical features of hump-nosed pit viper (Hypnale hypnale and Hypnale zara) envenoming in children

BACKGROUND

Bites by the hump-nosed pit vipers (HNPV) of the genus Hypnale are the commonest type of venomous snakebites in Sri Lanka. Their bites frequently cause local effects while rarely causing systemic envenoming, that may include acute kidney injury and coagulopathy. There are 3 species of genus Hypnale including H. hypnale, H. zara and H. nepa from which latter two are endemic to Sri Lanka. Virtually all studies on HNPV bites in Sri Lanka are focused on adults except two studies in paediatric group. The aims of this study were to describe the epidemiology and clinical manifestations of HNPV bites in a group of children admitted to a tertiary care hospital in Sri Lanka.

METHODOLOGY/PRINCIPAL FINDINGS

This was a prospective observational study carried out in Teaching Hospital Ratnapura, Sri Lanka over 27 months commencing from May 2020 including all children aged up to 14 years with the history of HNPV bites. There were 40 (56%) HNPV bites, of them 28 (70%) were males. The age was 84 months (50.2-120 months). Majority (n = 21;52.5%) were bitten during day-time (06:00-17:59) in home gardens (n = 20; 50%) on lower limbs (n = 24;60%). Most children (n = 30;75%) were admitted to the medical facility < 4 hours after the snakebite [90 min (40-210 min)] and the hospital stay was 4 days (3-5 days). Local envenoming was observed in 38 patients (95%) and systemic effects developed in 4 patients (10%) as mild coagulopathy. Local effects include local pain (n = 30; 94%), swelling (n = 38;95%), blistering (n = 11;27.5%), necrosis at the site of bite (n = 11; 27.5%), regional lymph node enlargement (n = 8;20%) and local bleeding (n = 4;10%). For the local effects, surgical interventions were needed in 10 children (25%) and 3 (7.5%) of them developed acute compartment syndrome leading to fasciotomy. Leucocytosis (n = 28;78%) and eosinophilia (n = 9;27%) were the prominent laboratory findings. All got recovered except in patients with fasciotomy who got permanent scar.

CONCLUSIONS/SIGNIFICANCE

Hump-nosed pit viper bites mostly cause local effects and rarely systemic envenoming in children. Compartment syndrome is common in children following their bites.

Systematic review and meta-analysis of global prevalence of neurotoxic and hemotoxic snakebite envenomation

Background

The World Health Organization estimates that there are approximately 5.4 million snakebites and 1.8-2.7 million cases of envenomation, with 81 410-137 880 deaths each year worldwide.

Aims

To estimate the prevalence of neurotoxic and haemotoxic snakebite envenomation through a comprehensive systematic review and meta-analysis.

Methods

We searched Medline/PubMed, Scopus and Cochrane Library up to January 2021 using keywords such as snakebite and snake envenomation. Bibliographic and random searches were also performed. Prospective or retrospective observational studies and randomized controlled trials were included for the review.

Results

We included 271 of 9711 studies published between 1963 and 2020. The pooled prevalence of snakebite from 188 studies with a total of 207 235 participants showed the highest prevalence in North America (69.20%; 95% confidence interval, CI: 57.06-81.34%) and lowest in Africa (28.10%; 95% CI: 22.22-33.98%). There was a pooled prevalence of 24.94% (95% CI: 22.84-27.03%) for haemotoxicity, with a highest prevalence of coagulopathy (43.76%; 95% CI: 33.15-54.37%). The overall prevalence of neurotoxicity was 38.20% (95% CI: 31.88-44.53%), with a highest prevalence of ptosis (53.57%; 95% CI: 38.51-68.62%).

Conclusion

There was a higher prevalence of snakebites in North America. The most prevalent haemotoxicity and neurotoxicity were coagulopathy and ptosis, respectively. The overall quality of evidence was good with a non-significant publication bias.