Snakes of medical importance in India: is the concept of the "Big 4" still relevant and useful?

Dimethyl ester of bilirubin ameliorates Naja naja snake venom-induced lung toxicity in mice via inhibiting NLRP3 inflammasome and MAPKs activation

Naja naja snake bite causes thousands of deaths worldwide in a year. N. naja envenomed victims exhibit both local and systemic reactions that potentially lead to death. In clinical practice, pulmonary complications in N. naja envenomation are commonly encountered. However, the molecular mechanisms underlying N. naja venom-induced lung toxicity remain unknown. Here, we reasoned that N. naja venom-induced lung toxicity is prompted by NLRP3 inflammasome and MAPKs activation in mice. Treatment with dimethyl ester of bilirubin (BD1), significantly inhibited the N. naja venom-induced activation of NLRP3 inflammasome and MAPKs both in vivo and in vitro (p < 0.05). Further, BD1 reduced N. naja venom-induced recruitment of inflammatory cells, and hemorrhage in the lung toxicity examined by histopathology. BD1 also diminished N. naja venom-induced local toxicities in paw edema and myotoxicity in mice. Furthermore, BD1 was able to enhance the survival time against N. naja venom-induced mortality in mice. In conclusion, the present data showed that BD1 alleviated N. naja venom-induced lung toxicity by inhibiting NLRP3 inflammasome and MAPKs activation. Small molecule inhibitors that intervene in venom-induced toxicities may have therapeutic applications complementing anti-snake venom.

Clinico-Epidemiological Profile, Trends, and Health-Related Outcomes of Snakebite Victims: A One-Year Prospective Study from Eastern India

INTRODUCTION

Snakebite envenomation is a significant life-threatening public health problem in Southeast Asia (SEA). In this region, India reported the largest number of snakebite deaths from 2000 to 2019 (1.2 million), with an average of 58,000 deaths yearly.

METHODS

This prospective observational study was carried out among snakebite victims at the emergency department (ED) of a tertiary care public sector hospital in eastern India.

RESULTS

A total of 145 cases of venomous snakebite were investigated. More than half (n = 81, 56%) of the snakebite victims were between 17 to 45 years. Most of the snakebite victims were male (68%) and were farmers (53%) by occupation. The majority of snakebites occurred during the daytime (76%) and while outdoors (67%). Most victims sustained a bite on the lower extremity (71%). The peak incidence of snakebites occurred from June to September (69%). Three-quarters of all patients were unaware of the required first aid measures following a snakebite. Among the 145 venomous snakebites, 48 were presumptively identified as the Indian cobra, 32 by the Indian krait, 56 by the Russel's viper, and 9 by saw-scaled viper. The mean duration from the snakebite to the onset of systemic effects in the Indian cobra was 52 ± 14.28 min, 66 ± 18.35 min in the Indian krait, 42 ± 13.47 min in Russel's viper, and 48 ± 16.38 min in saw-scaled viper. Respiratory failure was the commonly observed complication following an elapid envenomation. The mortality rate was 2.1% among the patients treated with antivenom.

CONCLUSIONS

Snakebite is considered an occupational hazard in India, commonly affecting the young population in their productive period. The peak incidence was during monsoon season, and the majority had neurotoxic envenomation following an elapid bite (55%) that contributed to the increased mortality and morbidity among young adults. Of the 145 patients, the majority (84%) recovered fully with treatment; 16% of the victims developed morbidity viz cellulitis, respiratory failure, acute renal failure, compartment syndrome, local tissue necrosis, intracerebral hemorrhage, and disseminated intravascular coagulation. Appropriate first aid measures and timely medical intervention can significantly improve the treatment outcome following snakebites.

Indian green pit vipers: A lesser-known snake group of north-east India

Green pit vipers are one of the most widely distributed group of venomous snakes in south-east Asia. In Indian, green pit vipers are found in the Northern and North-eastern states spreading across eastern and central India and one of the lesser studied venoms. High morphological similarity among them has been a long-established challenge for species identification, however, a total of six species of Indian green pit viper belonging to genus Trimeresurus, Popeia and Viridovipera has been reported from North-east India. Biochemical and biological studies have revealed that venom exhibits substantial variation in protein expression level along with functional variability. The symptoms of envenomation are painful swelling at bite site, bleeding, necrosis along with systemic toxicity such as prolonged coagulopathy. Clinical data of green pit viper envenomated patients from Demow community health centre, Assam advocated against the use of Indian polyvalent antivenom pressing the need for a suitable antivenom for the treatment of green pit viper envenomation. To design effective and specific antivenom for green pit vipers, unveiling the proteome profile of these snakes is needed. In this study, a comparative venomic of green pit vipers of Northern and North-eastern India, their clinical manifestation as well as treatment protocol has been reviewed.

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.

Naja naja snake venom-induced local toxicities in mice is by inflammasome activation

Snake bite envenomation causes tissue damage resulting in acute and chronic inflammatory responses. Inflammasome activation is one of the factors involved in tissue damage in a mouse model of snake envenomation. The present study examines the potency of Indian Big Four snake venoms in the activation of inflammasome and its role in local and systemic tissue toxicity. Among Indian Big Four snake venoms, Naja naja venom activated NLRP3 inflammasome in mouse macrophages. Activation of NLRP3 inflammasome was also observed in mouse foot paw and thigh muscle upon administration of N. naja venom. Intraperitoneal administration of N. naja venom cause systemic lung damage showed activation of NLRP3 inflammasome. Treatment with MCC950, a selective NLRP3 inflammasome inhibitor effectively inhibited N. naja venom-induced activation of caspase-1 and liberation of IL-1β in macrophages. In mice, MCC950 partially inhibited the activation of NLRP3 inflammasome in N. naja venom administered foot paw and thigh muscle. In conclusion, the present data showed that inflammasome is one of the host responses involved in N. naja snake venom-induced toxicities. The inhibition of inflammasome activation will provide new insight into better management of snake bite-induced local tissue damage.

The Need for Next-Generation Antivenom for Snakebite Envenomation in India

The limitations posed by currently available antivenoms have emphasized the need for alternative treatments to counteract snakebite envenomation. Even though exact epidemiological data are lacking, reports have indicated that most global snakebite deaths are reported in India. Among the many problems associated with snakebite envenomation, issues related to the availability of safer and more efficient antivenoms are of primary concern. Since India has the highest number of global snakebite deaths, efforts should be made to reduce the burden associated with snakebite envenoming. Alternative methods, including aptamers, camel antivenoms, phage display techniques for generating high-affinity antibodies and antibody fragments, small-molecule inhibitors, and natural products, are currently being investigated for their effectiveness. These alternative methods have shown promise in vitro, but their in vivo effectiveness should also be evaluated. In this review, the issues associated with Indian polyvalent antivenoms in neutralizing venom components from geographically distant species are discussed in detail. In a nutshell, this review gives an overview of the current drawbacks of using animal-derived antivenoms and several alternative strategies that are currently being widely explored.

A retrospective analysis of epidemiology, clinical features of envenomation, and in-patient management of snakebites in a model secondary hospital of Assam, North-east India

Assam, a Northeastern State of India, is inhabited by several venomous snake species causing substantial morbidity and mortality. The data on the epidemiology of snakebites and their management is underreported in this region. Hence, a secondary health-based retrospective study was carried out at Demow Model Hospital, Sivasagar, Assam, to evaluate the clinical and epidemiological profile of snakebite cases reported in this rural hospital and their management. Snakebites occurring between April 2018 to August 2022 were reviewed based on socio-demographic details of the patient, clinical symptoms, and treatment using a standard questionnaire. Out of the 1011 registered snakebite cases, 139 patients (13.7%) counted for venomous bites, among which 92 patients (66.19%) accounted for viper bites (green pit viper and Salazar's pit viper), and 30 patients (21.5%) were bitten by elapid snakes (Indian monocled Cobra, banded krait, and greater/lesser black krait). A maximum number of snakebite cases (80.5%) were reported from the interior rural villages and documented from July to September (51.3%). Elapid snake envenomed patients, except one, were successfully treated with commercial antivenom, neostigmine, and glycopyrrolate. Because commercial polyvalent antivenom against "Big Four" venomous snakes of India showed poor neutralization of pit-vipers envenomation; therefore, pit-viper bite patients were treated with repurposed drugs magnesium sulfate and glycerin compression dressing. Adverse serum reactions were reported only in 3 (11.1%) cases. The preventive measures and facilities adopted at the Demow Model Hospital significantly reduce snakebite death and morbidity; therefore, they can be s practised across various states in India as a prototype.

Peripheral Arterial Thrombosis following Russell's Viper Bites

Envenomings by Russell's viper ( Daboia russelii ), a species of high medical importance in India and other Asian countries, commonly result in hemorrhage, coagulopathies, necrosis, and acute kidney injury. Although bleeding complications are frequently reported following viper envenomings, thrombotic events occur rarely (reported only in coronary and carotid arteries) with serious consequences. For the first time, we report three serious cases of peripheral arterial thrombosis following Russell's viper bites and their diagnostic, clinical management, and mechanistic insights. These patients developed occlusive thrombi in their peripheral arteries and symptoms despite antivenom treatment. In addition to clinical features, computed tomography angiography was used to diagnose arterial thrombosis and ascertain its precise locations. They were treated using thrombectomy or amputation in one case that presented with gangrenous digits. Mechanistic insights into the pathology through investigations revealed the procoagulant actions of Russell's viper venom in standard clotting tests as well as in rotational thromboelastometry analysis. Notably, Russell's viper venom inhibited agonist-induced platelet activation. The procoagulant effects of Russell's viper venom were inhibited by a matrix metalloprotease inhibitor, marimastat, although a phospholipase A 2 inhibitor (varespladib) did not show any inhibitory effects. Russell's viper venom induced pulmonary thrombosis when injected intravenously in mice and thrombi in the microvasculature and affected skeletal muscle when administered locally. These data emphasize the significance of peripheral arterial thrombosis in snakebite victims and provide awareness, mechanisms, and robust strategies for clinicians to tackle this issue in patients.

Hump-Nosed Pit Viper Envenomation in Western Coastal India: A Case Series

The hump-nosed pit viper (HNPV) has historically been considered less medically significant, causing local envenomation, renal injury, and coagulopathy; however, now, it is known to cause life-threatening complications. We describe the clinical presentation, treatment, and complications of 3 confirmed HNPV bites from the state of Karnataka (southwest coastal India). Patient 1, an 88-y-old woman, reported with the live specimen and developed venom-induced consumption coagulopathy (VICC) and thrombotic microangiopathy leading to acute kidney injury requiring blood product transfusions and dialysis. Patient 2, a 60-y-old woman, reported 3 d after envenomation followed by treatment at another hospital where 30 vials of polyvalent anti-snake venom (ASV) were given. She developed VICC and acute kidney injury requiring dialysis. On Day 9 of treatment, she developed a pontine hemorrhage. She died after a transfer to another treatment center closer to her residence. Patient 3, a 25-y-old man, was brought to our emergency department 6 h after being envenomed. He received topical ayurvedic treatment before arrival. He was unconscious and found to have severe VICC with a massive middle cerebral artery infarct. All 3 patients received Indian polyvalent ASV, which does not cover HNPV envenomation, clearly demonstrating the absence of paraspecificity and neutralization in a clinical setting. To our knowledge, Hypnale hypnale envenomation has not previously been reported from Karnataka state. The diagnosis of HNPV envenomation in a country without snake venom detection kits, under-reporting despite serious complications, financial burdens on rural populations afflicted, and poor outcomes due to the lack of a specific antivenom are discussed.

Development of Wunderlich syndrome following a Russell's viper bite

Snakebite envenomation is a high priority neglected tropical disease that predominantly affects rural communities living in developing countries. Due to myriad of complications including coagulopathies, neurotoxicity, nephrotoxicity and local tissue destruction, treating snakebite victims is a major challenge for clinicians. Russell's viper (Daboia russelii) is one of the 'Big Four' venomous snakes in India, and it is responsible for the most snakebite-induced deaths and disabilities. Acute kidney injury occurs frequently following Russell's viper bites and it is a critical factor contributing to disabilities, deaths and excessive treatment costs. In addition to commonly observed envenomation effects, Russell's viper bites induce some rare complications such as priapism, sialolithiasis and splenic rupture. Here, we report a case of Wunderlich syndrome that developed in a 22-year-old male following a Russell's viper bite. The patient displayed severe coagulopathies, abdominal tenderness, and hypotension. Notably, a peri-nephric haematoma was identified through ultrasound and computerised tomographic imaging. The haemorrhage was successfully treated using angioembolisation, and the patient recovered without any difficulties. Although a clinical condition such as this is rare, it is important to create awareness among treating clinicians about its occurrence, diagnosis and clinical management.

Clinico-epidemiology and management of hump-nosed pit viper (Hypnale spp.) bites in dogs

Human envenoming from the bite of the abundant hump-nosed pit viper (Hypnale spp.) (HNPV) is a frequent occurrence with victims experiencing unpleasant and sometimes life-threatening consequences. Further, clinico-pathology, treatment and management measures in HNPV envenomed dogs are under recognized. Prospective investigations were performed to assess the clinico-pathology and management options for HNPV envenomed dogs brought to the University of Peradeniya’s Veterinary Teaching Hospital from January, 2012 to March 2018. We recorded the local and systemic manifestations, hematological and urinary abnormalities of 78 dogs in which HNPV bite had been witnessed by the owner. Mild swelling, extensive swelling, hemorrhagic blistering and hemorrhagic bullae at the site of bite were observed in 59%, 31%, 6% and 4% of the dogs, respectively. Some dogs were subjected to surgical excision of necrotized tissue including limb amputation. We observed the following systemic clinical effects in envenomed dogs: neurotoxicity (13%), acute kidney injury (AKI) (14%) and coagulopathy (16%). All dogs showed leukocytosis with mean white blood cell count of 25.25 × 10³/µL. Mild anemia and thrombocytopenia were detected in 29% of the dogs. There was a significant correlation between extent of local tissue injuries with length of hospitalization (LH). The mean time of coagulopathy observed was 21.3 h (IQR: 8–48 h). In coagulopathic dogs, there was a strong correlation between LH and extent of local tissue injury (r_s = 0.7751, P < 0.0001); LH and whole blood clotting time(CT) (rs = 1.0, P < 0.0001); PT and aPTT (r_s = 0.4712, P < 0.001). LH was significantly correlated with the development of AKI (p = 0.0013). Lack of specific antivenom (AVS) for HNPV envenoming provided an opportunity to study the remaining treatment options. Therefore, the study allowed the identification of local and systemic effects, hematological abnormalities, possible supportive treatments and drawbacks of management measures for envenomed dogs.

Isolation and Characterization of Two Postsynaptic Neurotoxins From Indian Cobra (Naja Naja) Venom

The Indian Cobra (Naja naja) is among the “Big Four” responsible for most of the snakebite envenoming cases in India. Although recent proteomic studies suggest the presence of postsynaptic neurotoxins in N. naja venom, little is known about the pharmacology of these toxins. We isolated and characterized α-Elapitoxin-Nn2a (α-EPTX-Nn2a; 7020 Da) and α-Elapitoxin-Nn3a (α-EPTX-Nn3a; 7807 Da), a short-chain and long-chain postsynaptic neurotoxin, respectively, which constitute 1 and 3% of N. naja venom. α-EPTX-Nn2a (100–300 nM) and α-EPTX-Nn3a (100–300 nM) both induced concentration-dependent inhibition of indirect twitches and abolished contractile responses of tissues to exogenous acetylcholine and carbachol, in the chick biventer cervicis nerve-muscle preparation. The prior incubation of tissues with Indian polyvalent antivenom (1 ml/0.6 mg) prevented the in vitro neurotoxic effects of α-EPTX-Nn2a (100 nM) and α-EPTX-Nn3a (100 nM). The addition of Indian polyvalent antivenom (1 ml/0.6 mg), at the t₉₀ time point, could not reverse the in vitro neurotoxicity of α-EPTX-Nn2a (100 nM). The in vitro neurotoxicity of α-EPTX-Nn3a (100 nM) was partially reversed by the addition of Indian polyvalent antivenom (1 ml/0.6 mg), as well as repeated washing of the tissue. α-EPTX-Nn2a displayed non-competitive antagonism of concentration-response curves to carbachol, with a pA₂ of 8.01. In contrast, α-EPTX-Nn3a showed reversible antagonism of concentration-response curves to carbachol, with a pA₂ of 8.17. De novo sequencing of α-EPTX-Nn2a and α-EPTX-Nn3a showed a short-chain and long-chain postsynaptic neurotoxin, respectively, with 62 and 71 amino acids. The important observation made in this study is that antivenom can reverse the neurotoxicity of the clinically important long-chain neurotoxin, but not the short-chain neurotoxin, from N. naja venom.

Venomics and antivenomics of Indian spectacled cobra (Naja naja) from the Western Ghats

Venom proteome profiling of Naja naja from the Western Ghats region in Kerala was achieved through SDS-PAGE and RP-HPLC followed by Q-TOF LC-MS/MS analysis, incorporating PEAKS and Novor assisted de novo sequencing methodologies. A total of 115 proteins distributed across 17 different enzymatic and non-enzymatic venom protein families were identified through conventional and 39 peptides through homology-driven proteomics approaches. Fourteen peptides derived through de novo complements the Mascot data indicating the importance of homology-driven approaches in improving protein sequence information. Among the protein families identified, glutathione peroxidase and endonuclease were reported for the first time in the Indian cobra venom. Immunological cross-reactivity assessed using Indian polyvalent antivenoms suggested that VINS showed better EC₅₀ (2.48 µg/mL) value than that of PSAV (6.04 µg/mL) and Virchow (6.03 µg/mL) antivenoms. Western blotting experiments indicated that all the antivenoms elicited poor binding specificities, especially towards low molecular mass proteins. Second-generation antivenomics studies revealed that VINS antivenom was less efficient to detect many low molecular mass proteins such as three-finger toxins and Kunitz-type serine protease Inhibitors. Taken together, the present study enabled a large-scale characterization of the venom proteome of Naja naja from the Western Ghats and emphasized the need for developing more efficient antivenoms.

A comparative cross-reactivity and paraspecific neutralization study on Hypnale hypnale, Echis carinatus, and Daboia russelii monovalent and therapeutic polyvalent anti-venoms

Envenoming by the hump-nosed pit viper (Hypnale hypnale) raises concern as it inflicts significant debilitation and death in the Western Ghats of India and in the adjacent island nation of Sri Lanka. In India, its medical significance was realized only during 2007 due to its misidentification as Echis carinatus and sometimes as Daboia russelii. Of late, several case reports have underlined the ineptness of the existing polyvalent anti-venom therapy against H. hypnale envenoming. Currently, H. hypnale bite has remained dreadful in India due to the lack of neutralizing anti-venom therapy. Hence, this study was undertaken to establish a systematic comparative, biochemical, pathological, and immunological properties of Sri Lankan H. hypnale venom alongside Indian E. carinatus, and D. russelii venoms. All three venoms differed markedly in the extent of biochemical activities including proteolytic, deoxyribonuclease, L-amino acid oxidase, 5'-nucleotidase, hyaluronidase, and indirect hemolytic activities. The venoms also differed markedly in their pathological properties such as edema, hemorrhage, myotoxic, cardiotoxic, and coagulant activities. The venoms showed stark differences in their protein banding pattern. Strikingly, the affinity-purified rabbit monovalent anti-venoms prepared against H. hypnale, E. carinatus, and D. russelii venoms readily reacted and neutralized the biochemical and pathological properties of their respective venoms, but they insignificantly cross-reacted with, and thus failed to show paraspecific neutralization of any of the effects of the other two venoms, demonstrating the large degree of variations between these venoms. Further, the Indian therapeutic polyvalent anti-venoms from VINS Bioproducts, and Bharath Serums and Vaccines failed to protect H. hypnale venom-induced lethal effects in mice.

A simple mortality risk prediction score for viper envenoming in India (VENOMS): A model development and validation study

BACKGROUND

Snakebite is a neglected problem with a high mortality in India. There are no simple clinical prognostic tools which can predict mortality in viper envenomings. We aimed to develop and validate a mortality-risk prediction score for patients of viper envenoming from Southern India.

METHODS

We used clinical predictors from a prospective cohort of 248 patients with syndromic diagnosis of viper envenoming and had a positive 20-minute whole blood clotting test (WBCT 20) from a tertiary-care hospital in Puducherry, India. We applied multivariable logistic regression with backward elimination approach. External validation of this score was done among 140 patients from the same centre and its performance was assessed with concordance statistic and calibration plots.

FINDINGS

The final model termed VENOMS from the term "Viper ENvenOming Mortality Score included 7 admission clinical parameters (recorded in the first 48 hours after bite): presence of overt bleeding manifestations, presence of capillary leak syndrome, haemoglobin <10 g/dL, bite to antivenom administration time > 6.5 h, systolic blood pressure < 100 mm Hg, urine output <20 mL/h in 24 h and female gender. The lowest possible VENOMS score of 0 predicted an in-hospital mortality risk of 0.06% while highest score of 12 predicted a mortality of 99.1%. The model had a concordance statistic of 0·86 (95% CI 0·79-0·94) in the validation cohort. Calibration plots indicated good agreement of predicted and observed outcomes.

CONCLUSIONS

The VENOMS score is a good predictor of the mortality in viper envenoming in southern India where Russell's viper envenoming burden is high. The score may have potential applications in triaging patients and guiding management after further validation.

A study on the clinical, epidemiological profile and the outcome of the snake bite victims in kashmir valley

Background:

Materials and Methods:

Results:

Conclusion:

A Tropical Kiss by a Malabar Pit Viper

Snakebite in India is often attributed to the "big 4," for which polyvalent anti-snake venom is effective. Also significant and less known is the burden of other venomous snakes, one of which is Trimeresurus malabaricus. We report a bite to the face of a tree climber by Trimeresurus malabaricus in the Western Ghats of India, which caused severe local envenomation in the form of facial edema and systemic signs of envenomation, including coagulopathy and hypotension. We discuss the role of thromboelastogram, infrared thermography, and routine diagnostics in this case, which led to the administration of Indian-made polyvalent anti-snake venom. The patient recovered and was discharged without any clinically evident physiological or physical dysfunction.

Prevention and improvement of clinical management of snakebite in Southern Asian countries: A proposed road map

In the Southern Asian countries, snakebite takes a substantial toll in terms of human life, inflicts acute morbidity and long term disability both physical and psychological, and therefore represents a neglected socio-economic problem and severe health issue that requires immediate medical attention. The 'Big Four' venomous snakes, viz. Daboia russelii, Naja naja, Bungarus caeruleus and Echis carinatus, are prominent, medically important species and are the most dangerous snakes of this region; therefore, the commercial polyvalent antivenom (PAV) contains antibodies against the venoms of these snakes. However, envenomations by species other than the 'Big Four' snakes are grossly neglected, and PAV is only partially effective in neutralizing the venom of these snakes. Many issues confounding effective treatment of snakebite are discussed in this review, and these hurdles preventing successful treatment of snakebite must be addressed. However, in South Asian countries, the pre-hospital treatment and appropriate first aid are equally important to mitigate the problem of snakebite and therefore, these issues are also highlighted here. Further, this review suggests a roadmap and guidelines for the prevention of snakebite and improvement of hospital management of snakebite in these Southern Asian countries.

Hypnale coagulopathy: snake envenomation of a different kind

Hypnale hypnale is a small pit viper that is known as the hump-nosed pit viper (HNV) or 'Merrem's hump-nosed pit viper' and is endemic to Sri Lanka and the Western Ghats of South India. Previously, it was thought that this viper bite would result in mild systemic or local envenomation, however, we now know that HNV bites could cause severe systemic toxicity and mortality. The most common systemic toxicity of this viper envenomation is coagulopathy, which is known as 'Hypnale coagulopathy'. Hypnale coagulopathy is quite different from the haemotoxicity caused by other vipers. In this paper, an effort has been made to discuss the unique and unpredictable nature of this coagulopathy due to Hypnale envenomation.

In vitro anti-venom potential of various solvent based leaf extracts of Andrographis serpyllifolia (Rottler ex Vahl) Wight against Naja naja and Daboia russelli

ETHNOPHARMACOLOGICAL RELEVANCE

Snake bite is a major occupational hazard in tropical and subtropical countries including India as per the World Health Organization. Naja naja (Indian cobra) and Daboia russelli (Russell's viper) are the two poisonous snakes commonly associated with human mortality in India. Andrographis serpyllifolia (Rottler ex Vahl) Wight has been documented in ethnobotanical records as a plant possessing potent anti-snake venom activity.

AIM OF THE STUDY

The present study is aimed for systematic evaluation of in vitro anti-venom potential of various solvent based leaf extracts of A. serpyllifolia against toxic venom enzymes of Naja naja and Daboia russelli.

MATERIALS AND METHODS

Different solvent based leaf extracts of A. serpyllifolia were tested against the snake venoms of Naja naja and Daboia russelli obtained from Irula Snake Catchers Industrial Co-operative Society Limited, Kancheepuram, Tamil nadu, India. Three different in vitro neutralization assays such as indirect hemolysis, procoagulent and lytic activities and seven in vitro enzyme inhibition assays such as protease, acetylcholinesterase, phosphomonoesterase, phosphodiesterase, 5'nucleotidase, phospholipase A2, hyaluronidase and post synaptic acetylcholine receptor binding activity were carried out according to standard protocols. The results were analyzed using the standard ANOVA procedures.

RESULTS

Among various solvent based leaf extracts of A. serpyllifolia tested, aqueous extract showed maximum neutralizing and inhibitory activities against Naja naja and Daboia russelli venoms.

CONCLUSIONS

The various in vitro enzymatic studies reveal that the aqueous leaf extract of A. serpyllifolia plant could inhibit most of the toxic enzymes of the Naja naja and Daboia russelli venoms which could be further confirmed by in vivo studies.

Venom-Induced Consumption Coagulopathy Unresponsive to Antivenom After Echis carinatus sochureki Envenoming

Snakebite envenoming is a serious and life-threatening but neglected problem in the tropics. The focus in the Indian subcontinent is usually on the Indian cobra (Naja naja), common krait (Bungarus caeruleus), Russell's viper (Daboia russelii), and Indian saw-scaled viper (Echis carinatus). The Indian polyvalent antivenom contains hyperimmunized horse antibodies against only these 4 species. However, regional intraspecific variations are important in viper envenomings, leading to marked differences in clinical presentation and response to the available polyvalent antivenom. Echis carinatus sochureki, a subspecies of Echis carinatus, has been linked to serious morbidity in the Thar Desert regions of Rajasthan, although consistent reports are lacking. We report a patient with prolonged venom-induced consumption coagulopathy owing to Echis carinatus sochureki envenoming who did not respond to Indian polyvalent antivenom in Jodhpur, India. Features of local and hemotoxic envenoming resolved after a week with supportive care. Echis sochureki venom has been shown to be different from Echis carinatus in terms of composition and in vitro neutralization by antivenom. Clinicians in the tropical desert regions must suspect Echis sochureki envenoming in the setting of nonresponsiveness to Indian polyvalent antivenom. This will help optimize antivenom use in these patients, preventing potentially life-threatening antivenom associated reactions. Because the usefulness of Indian polyvalent antivenom appears to be limited in this setting, there is an urgent need to advocate for region-specific antivenom or monovalent antivenom for this area.

First-hand knowledge about snakes and snake-bite management: an urgent need

Snake-bite is a well-known but fairly ignored medical problem in India. Lack of precise first aid knowledge for snake-bite is a substantial reason for its severe fatality in human beings. The present study is comprised of a pilot survey that assesses and evaluates the knowledge of people of different occupations (teachers, students, farmers, medical residents, and miscellaneous) about snakes and snake-bite management. The pilot survey was conducted through a well-structured open-ended questionnaire about experiences with snakes and snake-bites and first aid measures for accidental snake-bites. Proper knowledge of snakes and snake-bite management was either diminutive or absent in the majority of the subjects, especially amongst teachers. Even the medical professionals were not well acquainted with knowledge about snakes and snake-bite management. Only 13% knew about ‘big four’, 18% knew ‘dry bite’, and 21% of subjects knew about anti-snake venom (ASV) used in India. 39% of subjects knew about the whereabouts of traditional healer. Only 12% of subjects, mostly medical residents, knew of any bedside test for diagnosis of snake-bite, and 11% of respondents also knew of LD₅₀ of Indian cobra. A well-timed first aid treatment is always decisive in the management of life-threatening snake-bite cases but the present survey has found that most of the study groups had inadequate and little misleading fundamental knowledge comprising regional snakes, first aid measures for accidental snake-bite, and welfare schemes for snake-bite victims. Therefore, the present study proposes to conduct more such appraisals and strengthening of education curricula on snake-bite that would surely inculcate an adequate level of primary skill in ignorant societies.

Venomous snakebites: Rapid action saves lives-A multifaceted community education programme increases awareness about snakes and snakebites among the rural population of Tamil Nadu, India

The lack of public awareness surrounding the dangers of snakebite envenomation (SBE) is one of the most critical factors contributing to SBE-induced complications, and subsequently exacerbating the number of deaths and disabilities resulting from SBE. In this study, we deployed a multifaceted community education programme to educate students, healthcare professionals and members of the public in rural areas of Tamil Nadu, India about the dangers of SBE, appropriate first aid measures and the 'do's and don'ts' following a snakebite. An assessment of prior knowledge within these communities identified several misconceptions concerning snakes and SBE. Using a combination of direct engagement (estimated to reach over 200,000 people), information leaflets (200,000 distributed), posters, video documentaries, media and social media (>2.8 million engagements), over the course of one year (January to December 2019) we reached over 3 million people in rural Tamil Nadu (around 8% of population). Evaluation of community-based assemblies indicated that at least 90% of attendees were able to recall the key messages at the end of the events, and at least 85% were able to recall the key messages even after 12 months. Due to high demand, a one-day symposium was organised to provide clinical knowledge and training on SBE to 250 healthcare professionals in rural Tamil Nadu. Notably, an assessment of patient data (291 victims) collected from a snakebite referral hospital over the same 12-month period (2019) indicated that arrival time at hospital following a snakebite was significantly faster and the effective first aid measures were administered to patients who were aware of our activities compared to those that were not. Overall, our approach provides a framework on how to educate rural communities about the dangers of SBE and thereby, mitigate delayed SBE treatment leading to an overall reduction in SBE-induced mortality, morbidity, treatment costs and other socio-economic ramifications.

Knowledge of health workers on snakes and snakebite management and treatment seeking behavior of snakebite victims in Bhutan

Background

Published information on snakebite is rare in Bhutan although remarkably higher number of snakebites and associated deaths are reported from other South Asian countries.

Aims and methodology

Structured questionnaire was used to collect knowledge of health workers in snakebite management and health seeking behavior of snakebite victims as observed by health workers. Study was conducted in purposively sampled 10 Dzongkhags (district level administrative units) with higher incidence of snakebites.

Result

Heath workers scored 27–91% (with an average of 63%, SD = 14) for 52 questions related to snake identification and snakebite management. Among 118 health workers interviewed, 23% had adequate knowledge on snakes and snakebite management while 77% had inadequate knowledge. Among 32 Doctors, 63% of them scored above or equal to 75%. Health workers from Sarpang scored higher (76%, SD = 11) than those from other Dzongkhags. Snakebite victim's visit to local (traditional) healers prior to seeking medical help from hospital was observed by 75 (63%) health workers. Fifty one percent of health workers observed patients treated with local methods such as the use of black stone called Jhhar Mauro (believed to absorb snake venom), application of honey, rubbing of green herbal paste made up of Khenpa Shing (Artemisia myriantha Wallich ex Besser var. paleocephala [Pamp] Ling) and consumption of fluid made up of Neem leaf (Azadirachta indica Juss). Use of tight tourniquet as a first aid to snakebite was observed by 80% of the health workers.

Conclusion

Health workers lack confidence in snakebite management. Snakebite victims are likely to suffer from harmful local practices and traditional beliefs on local treatment practices. Empowering health workers with adequate knowledge on snakebite management and making locals aware in pre-hospital care of snakebites are needed to improve the pre- and in-hospital management of snakebite in Bhutan.

Snakebites affect people globally including Bhutan and snakes are source of fear and excitement. Major proportion (62.7%) of Bhutanese population who thrive on agro-farming, rearing livestock, and searching forest products are at risk of snake envenomations. Deaths due to snakebites are dependent upon use of first aid type, provisions available with the health facilities, and health seeking behaviors of snakebite victims. This multi-center study was conducted to assess the level of knowledge of health workers and its association with their demographic features and health seeking behavior of snakebite victims as observed by health workers using investigator administered structured questionnaire. We included 12 hospitals and a Basic Health Unit (BHU) from 10 snakebite prone Dzongkhags with 962 (84%) snakebites from January 2013 to December 2017 in the country. Among 118 health workers interviewed, 27 (23%) had adequate level of knowledge with remaining 91 (77%) having inadequate knowledge. Male health workers and Doctors had better level of knowledge than other study groups. Health workers from Sarpang scored higher compared to those from other Dzongkhags. A total of 42% (n = 50) health workers scored below 60% (31 or less correct responses for 52 questions), which demands requirement of training and inclusion of practice-oriented courses in training curriculum of health professionals for snakebite management. Often, use of traditional medication and less frequent adherence to WHO recommended first aid measures was observed by 5% (n = 6) respondents. The adoption of non-recommended treatment practices seems to delay proper treatment resulting in gangrene and associated complications.

Sodium oleate, arachidonate, and linoleate enhance fibrinogenolysis by Russell's viper venom proteinases and inhibit FXIIIa; a role for phospholipase A2 in venom induced consumption coagulopathy

Life-threatening symptoms produced by Russell's viper (RV, Daboia russelii) envenomation result largely from venom induced consumption coagulopathy (VICC). VICC is thought to be mediated to a large degree by venom serine and metalloproteinases, as well as by snake venom phospholipase A2 (svPLA2), the most abundant constituent of RV venom (RVV). The observation that the phenolic lipid anacardic acid markedly enhances proteolytic degradation of fibrinogen by RVV proteinases led us to characterize the chemical basis of this phenomenon with results indicating that svPLA2 products may be major contributors to VICC. RESULTS: Of the chemical analogs tested, the anionic detergents sodium dodecyl sulfate, sodium deoxycholate, N-lauryl sodium sarcosine, and the sodium salts of the fatty acids arachidonic, oleic and to a lesser extend linoleic acid were able to enhance fibrinogenolysis by RVV proteinases. Enhanced Fibrinogenolysis (EF) was observed with various venom size exclusion fractions containing different proteinases, and also with trypsin, indicating that conformational changes of the substrate and increased accessibility of otherwise cryptic cleavage sites are likely to be responsible for EF. In addition to enhancing fibrinogenolysis, sodium arachidonate and oleate were found to partially inhibit thrombin induced, factor XIIIa (FXIIIa) mediated ligation of fibrin chains. In clotting experiments with fresh blood RVV was found to disrupt normal coagulation, leading to small, partial clot formation, whereas RVV pretreated with the PLA2 inhibitor Varespladib induced rapid and complete clot formation (after 5 min) compared to blood alone. CONCLUSION: The observations that fatty acid anions and anionic detergents induce conformational changes that render fibrin(ogen) more susceptible to proteolysis by RVV proteinases and that RVV-PLA2 activity (which produces FFA) is required to render blood incoagulable in clotting experiments with RVV indicate a mechanism by which the activity of highly abundant RVV-PLA2 promotes degradation and depletion of fibrin(ogen) resulting in incoagulable blood seen following RVV envenomation (VICC).

Causes and Consequences of Snake Venom Variation

Snake venoms are mixtures of toxins that vary extensively between and within snake species. This variability has serious consequences for the management of the world’s 1.8 million annual snakebite victims. Advances in ‘omic’ technologies have empowered toxinologists to comprehensively characterize snake venom compositions, unravel the molecular mechanisms that underpin venom variation, and elucidate the ensuing functional consequences. In this review, we describe how such mechanistic processes have resulted in suites of toxin isoforms that cause diverse pathologies in human snakebite victims and we detail how variation in venom composition can result in treatment failure. Finally, we outline current therapeutic approaches designed to circumvent venom variation and deliver next-generation treatments for the world’s most lethal neglected tropical disease.

Delineating the venom toxin arsenal of Malabar pit viper (Trimeresurus malabaricus) from the Western Ghats of India and evaluating its immunological cross-reactivity and in vitro cytotoxicity

The venom protein components of Malabar pit viper (Trimeresurus malabaricus) were identified by combining SDS-PAGE and ion-exchange chromatography pre-fractionation techniques with LC-MS/MS incorporating Novor and PEAKS-assisted de novo sequencing strategies. Total 97 proteins that belong to 16 protein families such as L-amino acid oxidase, metalloprotease, serine protease, phospholipase A2, 5'-nucleotidase, C-type lectins/snaclecs and disintegrin were recognized from the venom of a single exemplar species. Of the 97 proteins, eighteen were identified through de novo approaches. Immunological cross-reactivity assessed through ELISA and western blot indicate that the Indian antivenoms binds less effectively to Malabar pit viper venom components compared to that of Russell's viper venom. The in vitro cell viability assays suggest that compared to the normal cells, MPV venom induces concentration dependent cell death in various cancer cells. Moreover, crude venom resulted in chromatin condensation and apoptotic bodies implying the induction of apoptosis. Taken together, the present study enabled in dissecting the venom proteome of Trimeresurus malabaricus and revealed the immuno-cross-reactivity profiles of commercially available Indian polyvalent antivenoms that, in turn, is expected to provide valuable insights on the need in improving antivenom preparations against its bite.

Mast cells and IgE in defense against lethality of venoms: Possible "benefit" of allergy[]

Physicians think of mast cells and IgE primarily in the context of allergic disorders, including fatal anaphylaxis. This 'bad side' of mast cells and IgE is so well accepted that it can be difficult to think of them in other contexts, particularly those in which they may have beneficial functions. However, there is evidence that mast cells and IgE, as well as basophils (circulating granulocytes whose functions partially overlap with those of mast cells), can contribute to host defense as components of adaptive type 2 immune responses to helminths, ticks and certain other parasites. Accordingly, allergies often are conceptualized as "misdirected" type 2 immune responses, in which IgE antibodies are produced against any of a diverse group of apparently harmless antigens, and against components of animal venoms. Indeed, certain unfortunate patients who have become sensitized to venoms develop severe IgE-associated allergic reactions, including fatal anaphylaxis, upon subsequent venom exposure. In this review, we will describe evidence that mast cells can enhance innate resistance, and survival, to challenge with reptile or arthropod venoms during a first exposure to such venoms. We also will discuss findings indicating that, in mice surviving an initial encounter with venom, acquired type 2 immune responses, IgE antibodies, the high affinity IgE receptor (FcεRI), and mast cells can contribute to acquired resistance to the lethal effects of both honeybee venom and Russell's viper venom. These findings support the hypothesis that mast cells and IgE can help protect the host against venoms and perhaps other noxious substances.

Prognosis and long-term outcomes of acute kidney injury due to snake envenomation

Background

Snakebite is a common occupational hazard in tropical countries. To date, the literature on snakebite-related acute kidney injury (AKI) has been limited by retrospective study designs, lack of uniformity in case definitions of AKI and limited follow-up. This study aims to identify the in-hospital outcomes and long-term changes in kidney function that follow haemotoxic envenomation.

Methods

All adult patients admitted with AKI following haemotoxic envenomation from January 2016 to June 2017 were recruited and followed up until July 2018. Predictors of in-hospital mortality was assessed. Long-term follow-up data on kidney function were collected from survivors.

Results

In total, 184 patients with haemotoxic envenomation and AKI were recruited. The mean age of the subjects was 42.2 years [95% confidence interval (CI) 40.3–44.7]. The majority were male (71.2%). The mortality of patients with haemotoxic envenomation was 21.5%. The mortality was considerably higher in patients with Kidney Disease: Improving Global Outcomes (KDIGO) Stage 3 AKI [relative risk (RR) 4.45 (95% CI 1.14–17.42)] and those who met KDIGO urine output criteria [RR 20.45 (95% CI 2.84–147.23)]. A Cox regression model identified mechanical ventilation [odds ratio (OR) 5.59 (95% CI 2.90–10.81)], hypotension [OR 2.48 (95% CI 1.31–4.72)] and capillary leak syndrome [OR 2.02 (95% CI 1.05–3.88)] as independent predictors of mortality. Long-term follow-up data were available for 73 patients. A total of 21 patients (28.7%) developed adverse renal outcomes (glomerular filtration rate <60 mL/min/1.73 m², urine albumin excretion >30 mg/g and new-onset hypertension or prehypertension).

Conclusions

AKI resulting from snake envenomation is associated with considerable risk of mortality. The greater the AKI stage the greater the likelihood of mortality. One-third of patients with AKI developed long-term complications like chronic kidney disease, prehypertension and hypertension over the follow-up period.

Proteomic Analysis of Human Blister Fluids Following Envenomation by Three Snake Species in India: Differential Markers for Venom Mechanisms of Action

Skin blistering as a result of snakebite envenomation is characteristic of some bites, however little is known regarding the mechanism of blister formation or the composition of the blister fluid. In order to investigate if blister fluid proteomes from humans suffering snakebite envenomation could provide insights on the pathophysiology of these skin alterations, blister fluid was collected from six patients upon presentation at a clinic in India bitten by three species of snakes, Daboia russelii (3), Hypnale hypnale (2), or Naja naja (1). Standard clinical data were recorded throughout the treatment. Approximately 805 proteins were identified in blister fluids using proteomic analyses. Informatics analyses of the proteomes identified the top biological response categories as: platelet degranulation, innate immune response, receptor-mediated endocytosis, complement activation, and blood coagulation. Hierarchical clustering did not show a clear segregation of patients' proteomes being associated with the species of snake involved, suggesting that either the proteomic profiles described reflect a general response to venom-induced tissue damage or more patient data sets will be required to observe significant differences. Finally, it is of interest that venom proteins were also identified in the blister fluids suggesting that this fluid may serve as a reservoir of venom biologically active proteins/toxins, and as such, may indicate the clinical value of removing blister fluid to attenuate further tissue damage.

Mortality due to snakebite and other venomous animals in the Indian state of Bihar: Findings from a representative mortality study

Background

Animal bites and stings contribute significantly to mortality in certain parts of the world. India accounts for the highest number of snakebites and related mortality globally. We report on mortality due to bite or sting of a venomous animal from a population-based study in the Indian state of Bihar which estimated the causes of death using verbal autopsy.

Methodology/principal findings

Interviews were conducted for all deaths that occurred from January 2012 to March 2014 in 109,689 households (87.1% participation) covering 627,658 population in 1,017 clusters representative of the state using the Population Health Metrics Research Consortium shortened verbal autopsy questionnaire. Cause of death was assigned using the SmartVA automated algorithm. The annualized mortality rate per 100,000 population due to snakebite, scorpion sting and other animals adjusted for age, sex and urban-rural population distribution of the state; and detailed contextual information on snakebites are reported. Deaths due to bite/sting of a venomous animal accounted for 10.7% of all deaths due to unintentional injuries, with an adjusted mortality rate of 6.2 (95% CI 6.0–6.3) per 100,000 population. The adjusted snakebite mortality rate was 4.4 (95% CI 4.3–4.6) which was significantly higher in the rural areas (4.8, 95% CI 4.7–5.0) and in females (5.5, 95% CI 5.3–5.7). Snakebites accounted for 7.6% of all unintentional injury deaths across all ages but for 33.3% of the deaths in 10–14 years age group. A similar proportion of snakebite deaths occurred while sleeping (30.2%), playing (30.2%) and during field/outdoor activities (27.9%). In these cases, 8.2% people were already dead when found, 34.7% had died before treatment could be provided, and 28 (57.1%) had died post treatment among whom 46.4% had sought treatment at a health facility, 25% with a traditional healer, and the rest from both. Death before reaching a health provider, non-availability of medicines or doctor, referral patterns, and sex-differentials in the context of snakebite deaths are reported. None of the verbatim specifically mentioned anti-venom being used for treatment. The adjusted mortality rate for scorpion sting was 0.9 (95% CI 0.8–0.9).

Conclusions

The findings from this large representative sample documents the magnitude of snakebite mortality in Bihar and highlight the circumstances surrounding the snakebite events that could facilitate prevention and intervention opportunities.

Cardiac arrest and atrial fibrillation in a patient after hump-nosed pit viper (Hypnale hypnale) bite

A 42-year-old previously healthy male patient died 16 days after a proven hump-nosed pit viper (Hypnale hypnale) envenoming due to multi-organ failure. On admission he had cardiac arrest that recovered from cardiopulmonary resuscitation then developed atrial fibrillation which was reverted to normal rhythm by application of synchronized electrical cardioversion. He also had persistent coagulopathy and thrombotic microangiopathy comprising the triad of microangiopathic haemolysis, acute kidney injury and thrombocytopenia. This is the second reported case with cardiac complications following hump-nosed pit viper bites in Sri Lanka.

Infrequent use of medicinal plants from India in snakebite treatment

Snakes have fascinated humankind for millennia. Snakebites are a serious medical, social, and economic problem that are experienced worldwide; however, they are most serious in tropical and subtropical countries. The reasons for this are 1) the presence of more species of the most dangerous snakes, 2) the inaccessibility of immediate medical treatment, and 3) poor health care. The goal of this study was to collect information concerning rare, less utilized, and less studied medicinal plants. More than 100 plants were found to have potential to be utilized as anti-snake venom across India. Data accumulated from a variety of literature sources revealed useful plant families, the parts of plants used, and how to utilize them. In India, there are over 520 plant species, belonging to approximately 122 families, which could be useful in the management of snakebites. This study was conducted to encourage researchers to create herbal antidotes, which will counteract snake venom. These may prove to be an inexpensive and easily assessable alternative, which would be of immense importance to society. Plants from families such as Acanthaceae, Arecaceae, Apocynaceae, Caesalpiniaceae, Asteraceae, Cucurbitaceae, Fabaceae, Euphorbiaceae, Lamiaceae, Rubiaceae, and Zingiberaceae are the most useful. In India, experts of folklore are using herbs either single or in combination with others.

Purification and partial characterization of an anticoagulant PLA2 from the venom of Indian Daboia russelii that induces inflammation through upregulation of proinflammatory mediators

The present study describes the purification and partial characterization of a basic anticoagulant PLA2 enzyme named as Rv(i) PLA2 from the venom of Indian Daboia russelii. The molecular mass of the protein was found to be 13,659.65 Da, and peptide mass fingerprinting revealed that it belongs to group II PLA2 family. The peptide sequence showed similarity to uncharacterized basic PLA2 enzyme having an accession no. of P86368 reported from Sri Lankan D. russelii. Rv(i) PLA2 exhibited strong phospholipase A2 and anticoagulant activity. It also induced expression of COX-2 and TNF-α mRNA in a dose-dependent manner in phorbol 12-myristate 13-acetate differentiated THP-1 cells, which play a crucial role during inflammation. Chemical modification of His residue in Rv(i) PLA2 with p-bromophenacyl bromide abolished the enzymatic, anticoagulant, and inflammatory activities. The result indicates that the catalytic site of Rv(i) PLA2 might play a vital role in inducing inflammation at the bite site during D. russelii envenomation.

Comparison of proteomic profiles of the venoms of two of the 'Big Four' snakes of India, the Indian cobra (Naja naja) and the common krait (Bungarus caeruleus), and analyses of their toxins

Snake venoms are mixtures of biologically-active proteins and peptides, and several studies have described the characteristics of some of these toxins. However, complete proteomic profiling of the venoms of many snake species has not yet been done. The Indian cobra (Naja naja) and common krait (Bungarus caeruleus) are elapid snake species that are among the 'Big Four' responsible for the majority of human snake envenomation cases in India. As understanding the composition and complexity of venoms is necessary for successful treatment of envenomation in humans, we utilized three different proteomic profiling approaches to characterize these venoms: i) one-dimensional SDS-PAGE coupled with in-gel tryptic digestion and electrospray tandem mass spectrometry (ESI-LC-MS/MS) of individual protein bands; ii) in-solution tryptic digestion of crude venoms coupled with ESI-LC-MS/MS; and iii) separation by gel-filtration chromatography coupled with tryptic digestion and ESI-LC-MS/MS of separated fractions. From the generated data, 81 and 46 different proteins were identified from N. naja and B. caeruleus venoms, respectively, belonging to fifteen different protein families. Venoms from both species were found to contain a variety of phospholipases A₂ and three-finger toxins, whereas relatively higher numbers of snake venom metalloproteinases were found in N. naja compared to B. caeruleus venom. The analyses also identified less represented venom proteins including L-amino acid oxidases, cysteine-rich secretory proteins, 5'-nucleotidases and venom nerve growth factors. Further, Kunitz-type serine protease inhibitors, cobra venom factors, phosphodiesterases, vespryns and aminopeptidases were identified in the N. naja venom, while acetylcholinesterases and hyaluronidases were found in the B. caeruleus venom. We further analyzed protein coverage (Lys/Arg rich and poor regions as well as potential glycosylation sites) using in-house software. These studies expand our understanding of the proteomes of the venoms of these two medically-important species.

Clinicopathological spectrum of snake bite-induced acute kidney injury from India

AIM

To study the clinico-pathological spectrum of snake bite-induced acute kidney injury (AKI).

METHODS

A retrospective study of patients admitted at Indira Gandhi Medical College Hospital, Shimla with snake bite-induced AKI from July 2003 to June 2016. Medical records were evaluated for patient’s information on demographic, clinical characteristics, complications and outcome. Outcomes of duration of hospital stay, requirement for intensive care unit support, treatment with dialysis, survival and mortality were analyzed. The survival and non survival groups were compared to see the difference in the demographic factors, clinical characteristics, laboratory results, and complications. In patients subjected to kidney biopsy, the findings of histopathological examination of the kidney biopsies were also analyzed.

RESULTS

One hundred and twenty-one patients were diagnosed with snake bite-induced AKI. Mean age was 42.2 ± 15.1 years and majority (58%) were women. Clinical details were available in 88 patients. The mean duration of arrival at hospital was 3.4 ± 3.7 d with a range of 1 to 30 d. Eighty percent had oliguria and 55% had history of having passed red or brown colored urine. Coagulation defect was seen in 89% patients. The hematological and biochemical laboratory abnormalities were: Anemia (80.7%), leukocytosis (75%), thrombocytopenia (47.7%), hyperkalemia (25%), severe metabolic acidosis (39.8%), hepatic dysfunction (40.9%), hemolysis (85.2%) and rhabdomyolysis (68.2%). Main complications were: Gastrointestinal bleed (12.5%), seizure/encephalopathy (10.2%), hypertension, pneumonia/acute respiratory distress syndrome (ARDS) and disseminated intravascular coagulation (9.1% each), hypotension and multi organ failure (MOF) (4.5% each). Eighty-two percent patients required renal replacement therapy. One hundred and ten (90.9%) patient survived and 11 (9.1%) patients died. As compared to the survival group, the white blood cell count (P = 0.023) and bilirubin levels (P = 0.006) were significant higher and albumin levels were significantly lower (0.005) in patients who died. The proportion of patients with pneumonia/ARDS (P = 0.001), seizure/encephalopathy (P = 0.005), MOF (P = 0.05) and need for intensive care unit support (0.001) was significantly higher and duration of hospital stay was significantly shorter (P = 0.012) in patients who died. Kidney biopsy was done in total of 22 patients. Predominant lesion on kidney biopsy was acute tubular necrosis (ATN) in 20 (91%) cases. In 11 cases had severe ATN and in other nine (41%) cases kidney biopsy showed features of ATN associated with mild to moderate acute interstitial nephritis (AIN). One patient only had moderate AIN and one had patchy renal cortical necrosis (RCN).

CONCLUSION

AKI due to snake bite is severe and a high proportion requires renal replacement therapy. On renal histology ATN and AIN are common, RCN is rare.

A mixed toxidrome presenting with bilateral ptosis with normal pupils: The first case in the literature

Snakebite is an environmental hazard associated with a significant morbidity and mortality. Two main types of toxicity occur due to snakebite, namely vasculotoxicity and neurotoxicity. Neurotoxic snakebites present mainly with bilateral ptosis with dilated pupils and/or difficulty in breathing. Jatropha curcas belongs to the family Euphorbiaceae and is commonly referred to as “Ratanjyot” in Gujarati. It has got many medicinal uses such as anticancerous properties and bio-oil. There are very few cases of its toxicity in adults. Toxicity from it causes meiosis, vomiting, diarrhea, etc., We will hereby discuss one such patient who consumed J. curcas seeds intentionally, became drowsy and accidentally got bit by a snake, and then, the patient started having bilateral ptosis, but with normal-sized pupils. There is no case reported yet in the literature mentioning the combined toxicity of snakebite and J. curcas, so we thought to publish this first case report of its kind in the world, thus discussing its diagnosis, symptoms, and treatment modalities.

Attempted suicide by snake bite: A case study

Snake bite is an important public health issue in India and is almost always accidental in manner. Suicide by snake bite or injection of snake venom is extremely rare. Suicidal ideation and behavior is known to be influenced by various socio-economic and psychological factors. The method employed for suicide is also influenced by the occupation of the victim. We report a case where a snake charmer had attempted suicide by inflicting a bite by a monocled cobra.

The Mast Cell-IgE Paradox: From Homeostasis to Anaphylaxis

Mast cells and IgE are so inextricably linked to the pathology of allergic disorders, including fatal anaphylaxis, that it can be difficult to think of them in other contexts. Surely, we do not have mast cells and IgE so that we can eat a peanut and die! It is thought that mast cells and IgE and basophils (circulating granulocytes, whose functions partially overlap with those of mast cells) can contribute to host defense as components of adaptive T helper cell type 2 immune responses to helminths, ticks, and certain other parasites. Accordingly, it was suggested that allergies are misdirected type 2 immune responses in which IgE antibodies are produced against any of a broad variety of apparently harmless antigens. However, components of animal venoms also can sensitize individuals to develop severe IgE-associated allergic reactions, including fatal anaphylaxis, on subsequent venom exposure. Here, I describe evidence that mast cells can enhance innate host resistance to reptile or arthropod venoms during responses to an initial exposure to such venoms and that acquired type 2 immune responses, IgE antibodies, the high-affinity IgE receptor FcεRI, and mast cells can contribute toward acquired resistance in mice to the lethal effects of honeybee or Russell's viper venom. These findings support the hypothesis that mast cells and IgE can help protect the host against noxious substances.

An eleven year old boy with pain abdomen and early morning neuroparalytic syndrome

An 11 year old boy presented with pain abdomen and tenderness all over body when he got up from sleep early in the morning and subsequently had one vomiting after 30 min. He had no other significant past medical history. The child was shifted to nearby health facility where he was managed as a case of acute abdomen on the basis of suggestive history and clinical findings. Within 2 h after the onset of clinical features suggestive of acute abdomen the patient went on to develop marked ptosis and flaccid quadriplegia. The young boy underwent a sequence of clinical tests which were noncontributory. Based on the clinical picture, a differential diagnosis of hypokalemic paralysis, botulism, Miller Fischer syndrome and EMNS were considered. Through exclusion, the most probable diagnosis for the symptoms was elapid envenomation hence he was started on anti-snake venom (ASV) with working diagnosis of EMNS. Within 2 h, he began to show improvement. This recovery with ASV suggests the possibility of elapid envenomation.