Snakebite nephropathy (Review Article)

Naja nigricincta nigricincta venom, a murine model. Evaluation of skeletal and cardio-myonecrosis, kidney injury and inflammatory response along with neutralisation efficacy by the SAIMR/SAVP - And EchiTAb-Plus-ICP polyvalent antivenoms

African spitting cobra, Naja nigricincta nigricincta (Zebra snake), envenomation is an important cause of snakebite morbidity and mortality in Namibia. The snake is endemic to central and northern Namibia as well as southern Angola. The venom is mainly cytotoxic, resulting in aggressive dermo-necrosis and often accompanied by severe systemic complications. No specific antivenom exists. Rhabdomyolysis, systemic inflammatory response, haemostatic abnormalities, infective necrotising fasciitis as well as acute kidney failure have been documented. Based on murine models, this study assessed SAVP/SAIMR - and EchiTAb-Plus-ICP polyvalent antivenom neutralisation as well as subdermal necrosis. Additional muscle, cardiac, kidney and lung histology, creatine kinase measurements and post-mortems were performed. An intravenous median lethal dose (LD50) of Naja nigricincta nigricincta venom was determined at 18.4 (CI: 16.3; 20.52) μg and a subdermal lethal dose at 15.3(CI: 12.96; 17.74)μg. The SAIMR/SAVP polyvalent antivenom median effective dose (ED50) was 1.2 ml antivenom/1 mg venom equating to a potency (WHO) of 1 ml antivenom neutralising 0.63 mg venom and approximately 240 ml (24 vials) needed for initial treatment. The ED50 of the EchiTAb-Plus-ICP was 1 ml antivenom/1 mg venom and a potency of 65 mg venom/ml antivenom (3.3 x LD50), estimating 230 ml (23 vials) for treatment. Histology and serology (creatine kinase) evidenced venom induced skeletal myotoxicity, which was not prevented by the antivenoms tested. Cardiac myonecrosis, an inflammatory response, direct venom kidney tubular necrosis and cardio-pulmonary failure were documented.

Acute phase reactions in Daboia siamensis venom and fraction-induced acute kidney injury: the role of oxidative stress and inflammatory pathways in in vivo rabbit and ex vivo rabbit kidney models

Background

This study examines the direct nephrotoxic effects of Daboia siamensis venom (RVV) and venom fractions in in vivo and isolated perfused kidneys (IPK) to understand the role of inflammation pathways and susceptibility to oxidative stress in venom or fraction-induced acute renal failure.

Methods

We administered RVV and its venom fractions (PLA2, MP, LAAO, and PDE) to rabbits in vivo and in the IPK model. We measured oxidative stress biomarkers (SOD, CAT, GSH, and MDA) in kidney tissue, as well as inflammatory cytokines (TNF-α, IL-1β, IFN-γ, IL-4, IL-5, and IL-10), MDA and GSH levels in plasma and urine. We also calculated fractional excretion (FE) for pro-/anti-inflammatory cytokines and oxidative stress biomarkers, including the ratios of pro-/anti-inflammatory cytokines in urine after envenomation.

Results

In both kidney models, significant increases in MDA, SOD, CAT, and GSH levels were observed in kidney tissues, along with elevated concentrations of MDA and GSH in plasma and urine after injecting RVV and venom fractions. Moreover, RVV injections led to progressive increases in FEMDA and decreases in FEGSH. The concentrations of IL-4, IL-5, IL-10, IFN-γ, and TNF-α in plasma increased in vivo, as well as in the urine of the IPK model, but not for IL-1β in both plasma and urine after RVV administrations. Urinary fractional excretion of TNF-α, IL-1β, IFN-γ, IL-4, IL-5, and IL-10 tended to decrease in vivo but showed elevated levels in the IPK model. A single RVV injection in vivo disrupted the balance of urinary cytokines, significantly reducing either the TNF-α/IL-10 ratio or the IFN-γ/IL-10 ratio.

Conclusion

RVV induces renal tubular toxicity by increasing oxidative stress production and elevating inflammatory cytokines in urine. During the acute phase of acute kidney injury, the balance of urine cytokines shifts toward anti-inflammatory dominance within the first two hours post-RVV and venom fractions.

Diosmin: A Daboia russelii venom PLA2s inhibitor- purified, and characterized from Oxalis corniculata L medicinal plant

ETHNOPHARMACOLOGICAL RELEVANCE

Oxalis corniculata L is a medicinal plant that belongs to the Oxalidaceae family. It is a little, slow-growing plant with a frail appearance typically found in mild temperate and tropical areas like Pakistan and India. This plant also includes many other bioactive substances, including alkaloids, flavonoids, terpenoids, cardiac glycosides, saponins, phlobatannins, and steroids.

AIM OF THE STUDY

To investigate the anti-inflammatory effects of Compound diosmin, which is derived from Oxalis corniculata L, on VRV-PL-5 and VRV-PL-8a isolated from Vipera russelli.

MATERIALS AND METHODS

Extraction, purification, and characterization of bioactive by TLC, HPTLC, FT-IR analysis, UV-Vis spectrophotometer, LC-MS/MS Analysis, NMR, XRD Analysis, In vitro evaluation, Circular dichroism spectroscopy, in vivo, and in silico studies.

RESULTS

In this study, the extract of Oxalis corniculata was evaluated for its in vitro and in vivo anti-inflammatory effect against PLA2. The methanolic extract decreased hemolytic activity by about 60% at 1:75 w/w and neutralized the hemolytic activity completely at 1:100 w/w concentration. Diosmin inhibited VRV-PL-5 and VRV-PL-8a in a dose-dependent manner, with the extent of inhibition being about 56% for VRV-PL-5120 μM and VRV-PL-8a by 62% at the same concentration with IC50 concentrations of 87.08 μM for VRV-PL-5 and 82.08 μM for VRV-PL-8a, while at 75 μM. Diosmin inhibited the hemolytic activity of VRV-PL-5 by about 85%, and at the same concentration, VRV-PL-8a inhibited by about 75%. UV-CD spectra at the IC50 concentration of diosmin disrupted the secondary structure of VRV-PL-5 &VRV-PL-8a. In vivo, studies showed decreased myotoxicity and cardiotoxicity of the VRV-PL-5 &VRV-PL-8a, which was seen in the decrease in cytoplasmic markers LDH and CPK levels in the serum when incubated with diosmin. Furthermore, Histopathological studies of Muscles and lungs revealed that diosmin considerably protects against cellular abnormality caused by VRV-PL-5 & VRV-PL-8a. Molecular docking, MM/GBSA, and molecular dynamics simulation studies show that the diosmin is a potent inhibitor for VRV-PL-5 and VRV-PL-8a.

CONCLUSION

This study shows that diosmin is a potentially effective VRV-PL-5 and VRV-PL-8a.

Serum Cholesterol Concentration on Admission in 415 Dogs Envenomated by Daboia (Vipera) palaestinae as a Marker of Envenomation Severity and Outcome-A Retrospective Study

Daboia (Vipera) palaestinae (Dp), accounts for most envenomations in humans and dogs in Israel. In humans envenomed by Dp, serum cholesterol concentration (sChol) is inversely correlated with envenomation severity. This study examined the utility of sChol upon admission in dogs envenomed by Dp as an envenomation severity and outcome marker. Data upon admission, including sChol, were retrospectively collected from the medical records of dogs with proven Dp envenomation. The study included 415 dogs. The mortality rate was 11%. The heart rate upon admission was higher in non-survivors than in survivors. Signs of bleeding or hematoma and circulatory shock signs were more frequent among non-survivors compared to survivors. sChol, the platelet count, and serum albumin concentration (sAlb) were lower, while serum creatinine concentration was higher among non-survivors. sChol and sAlb were moderately, positively, and significantly correlated. sChol was significantly, negatively, albeit weakly, correlated with the length of hospitalization and the heart rate. sChol was lower in dogs admitted >12 h post-envenomation than in those admitted later. In dogs, sChol upon admission is a potential marker of severity and outcome of Dp envenomation. The platelet count, sAlb, and sCreat might also be potential markers.

Renal functional and structural alterations induced by intramuscular injection of Bothrops leucurus venom

Acute kidney injury (AKI) is the main cause of death from Bothrops snakebite. Although many studies have investigated the nephrotoxicity induced by other Bothrops species, no study has assessed the renal alterations induced by intramuscular (i.m.) injection of Bothrops leucurus venom. In this study, we evaluated the nephrotoxicity induced by B. leucurus venom by analyzing renal function and histology. Wistar rats were submitted to i. m. injection of B. leucurus venom or saline and divided into two groups: Control group (C), rats submitted to i. m. injections of saline, and B. leucurus group (Bl), rats submitted to i. m. injections of B. leucurus venom (1 mg/kg). After venom or saline injection, serum and urine were collected to measure creatinine, albumin, sodium, and potassium levels. The glomerular filtration rate (GFR), urinary flow urinary, creatinine/serum creatinine ratio, and albuminuria-urinary creatinine ratio were determined. All rats were euthanized 72 h following the injections, and the kidneys were removed for histology and immunohistochemical studies. B. leucurus experimental envenoming was accompanied by an increase of 236% in serum creatine kinase activity in the Bl group. The weights of the right and left kidneys were, respectively, 26 and 22% higher in rats of the Bl group than in control rats. Regarding renal function, the Bl group showed a decrease of 37% in GFR compared to control group. The rats of the Bl group also presented increased cortical (8.20 ± 1.35) and medullar (6.17 ± 2.00) tubulointerstitial lesion area when compared to control group (0.02 ± 0.00) (1.20 ± 0.73), respectively. The number of macrophages was also higher in the renal cortex (6.66 ± 0.06) and medulla (1.22 ± 0.10) of rats from the Bl group when compared to control rats (1.04 ± 0.55), (0.65 ± 0.10), respectively. Our results indicate that B. leucurus venom promoted significant histological and functional renal alterations following intramuscular inoculation, which simulates the majority of snakebites observed in the clinical practice.

Clinical Profile and Pharmacological Management of Snakebites in Community Care Units: A Retrospective Study Using Two Military Hospital Databases in South Thailand

Snakebite envenoming is an occupational hazard in remote rural areas of South Thailand, where the highest incidence of snakebites is reported. In this work, a hospital-based retrospective study of snakebite patients from 2012 to 2022 at Fort Wachirawut Hospital and Fort Thepsatrisrisunthon Hospital, located in Nakhon Si Thammarat province, Thailand was conducted. Data from the laboratory investigation, physical examinations of snakebite victims, and clinical management, including pharmacological and non-pharmacological treatments, were evaluated. A total of 54 snakebite victims were included. The median age of patients was 49 years (IQR, 28 to 63). Males accounted for 74.1% of all participants. The majority of patients were bitten by Malayan pit vipers (68.5%), followed by unidentified snakes (18.5%), other non-venomous snakes (7.4%), and cobras (5.6%). The most common clinical manifestations were swelling (90.2%) and local pain (73.2%). One patient experienced respiratory failure following an envenoming by an unidentified venomous snake. No deaths were observed in this study. In total, 24 patients received antivenom administration (44.4%), most of whom were from Fort Wachirawut Hospital. Patients who were administered antivenom showed a median admission duration of three days (IQR, 3 to 4), compared with two days (IQR, one to three) for those who did not receive antivenom treatment (p < 0.001). In addition, paracetamol and prophylactic antibiotics, namely, amoxicillin-clavulanate and dicloxacillin, were the most common pharmacotherapies following snakebites. Overall, it was observed that these two community hospitals undertook appropriate clinical management under the standard guidelines for snakebite patients. This might be due to the effective emergency management, facilities, and clinical consultations. Finally, the management process in the medical teams also plays a crucial role in minimizing the severity of snakebite outcomes.

Fangs in the Ghats: Preclinical Insights into the Medical Importance of Pit Vipers from the Western Ghats

The socioeconomic impact of snakebites in India is largely attributed to a subset of snake species commonly known as the 'big four'. However, envenoming by a range of other clinically important yet neglected snakes, a.k.a. the 'neglected many', also adds to this burden. The current approach of treating bites from these snakes with the 'big four' polyvalent antivenom is ineffective. While the medical significance of various species of cobras, saw-scaled vipers, and kraits is well-established, the clinical impact of pit vipers from regions such as the Western Ghats, northeastern India, and the Andaman and Nicobar Islands remains poorly understood. Amongst the many species of snakes found in the Western Ghats, the hump-nosed (Hypnale hypnale), Malabar (Craspedocephalus malabaricus), and bamboo (Craspedocephalus gramineus) pit vipers can potentially inflict severe envenoming. To evaluate the severity of toxicity inflicted by these snakes, we characterised their venom composition, biochemical and pharmacological activities, and toxicity- and morbidity-inducing potentials, including their ability to damage kidneys. Our findings highlight the therapeutic inadequacies of the Indian and Sri Lankan polyvalent antivenoms in neutralising the local and systemic toxicity resulting from pit viper envenomings.

Medically important snakes and snakebite envenoming in Iran

Snakebite is a common health condition in Iran with a diverse snake fauna, especially in tropical southern and mountainous western areas of the country with plethora of snake species. The list of medically important snakes, circumstances and effects of their bite, and necessary medical care require critical appraisal and should be updated regularly. This study aims to review and map the distributions of medically important snake species of Iran, re-evaluate their taxonomy, review their venomics, describe the clinical effects of envenoming, and discuss medical management and treatment, including the use of antivenom. Nearly 350 published articles and 26 textbooks with information on venomous and mildly venomous snake species and snakebites of Iran, were reviewed, many in Persian (Farsi) language, making them relatively inaccessible to an international readership. This has resulted in a revised updated list of Iran's medically important snake species, with taxonomic revisions of some, compilation of their morphological features, remapping of their geographical distributions, and description of species-specific clinical effects of envenoming. Moreover, the antivenom manufactured in Iran is discussed, together with treatment protocols that have been developed for the hospital management of envenomed patients.

A case of fatal envenomation by a captive puff adder (Bitis arietans) in Malaysia

The Puff Adder (Bitis arietans) is a viper native to Africa and the Middle East. Envenomation by this species often requires the administration of appropriate antivenom in order to achieve a favorable outcome. A patient was bitten in both hands by a captive B. arietans presented to a teaching hospital in Malaysia. The patient developed painful progressive swelling on both limbs that extended to the chest, hypotension, hypokalemia with worsening anemia, thrombocytopenia, coagulopathy, and severe metabolic acidosis. The patient was managed supportively while waiting for the appropriate antivenom, Antivipmyn-Africa, from the Singapore Zoo. The patient developed cardiorespiratory arrest twice and did not recover from the second. The patient was pronounced dead 23 hours post-incident. The local unavailability of the appropriate antivenom may be the most important factor that contributed to the patient's death. There is also a need to amend the Malaysian Wildlife Act in order to prevent such cases from recurring.

Bothrops (Fer-de-lance) snakebites in the French departments of the Americas (Martinique and Guyana): Clinical and experimental studies and treatment by immunotherapy

Snakebite envenomation is a relevant medical hazard in French Guiana and Martinique, two French territories in the Americas. All snakebite envenomations in Martinique are inflicted by the endemic viperid species Bothrops lanceolatus, whereas Bothrops atrox is responsible for the majority of snakebites in French Guiana, although other venomous snake species also occur in this South American territory. This review summarizes some of the key aspects of the natural history of these species, as well as of their venom composition, the main clinical manifestations of envenomations, and their treatment by antivenoms. B. atrox venom induces the typical set of clinical manifestations characteristic of Bothrops sp. venoms, i.e., local tissue damage and systemic alterations associated with coagulopathies, hemorrhage, hemodynamic alterations, and acute kidney injury. In the case of B. lanceolatus venom, in addition to some typical features of bothropic envenomation, a unique and severe thrombotic effect occurs in some patients. The pathogenesis of this effect remains unknown but may be related to the action of venom components and inflammatory mediators on endothelial cells in the vasculature. A monospecific antivenom has been successfully used in Martinique to treat envenomations by B. lanceolatus. In the case of French Guiana, a polyvalent antivenom has been used for some years, but it is necessary to assess the preclinical and clinical efficacy against viperid venoms in this country of other antivenoms manufactured in the Americas.

Does snake envenoming cause chronic kidney disease? A cohort study in rural Sri Lanka

BACKGROUND

There is limited information on the risk of chronic kidney disease (CKD) following snakebite and its relationship with chronic interstitial nephritis in agricultural communities (CINAC). We aimed to investigate CKD in patients with a confirmed snakebite in rural Sri Lanka.

METHODS

Patients prospectively recruited to the Anuradhapura snakebite cohort with authenticated bites were followed up. Two groups of patients were followed up: 199 patients in group I with a snakebite (August 2013-October 2014), reviewed after 4 years, and 168 patients in group II with a snakebite (May 2017-August 2018), reviewed after one year, with serum creatinine (estimated glomerular filtration rate [eGFR]) and urinary albumin to creatinine ratio (ACR).

RESULTS

There were 12/199 (6%) in group I and 9/168 (5%) in group II with AKI following snakebite; 3/12 in group I and 2/9 in group II had haemodialysis. On review after 1 and 4 years, no patient had CKD and all had an eGFR ≥60 mL/min/1.73m². Of 234 patients with a creatinine measured on discharge, 17/140 in group I and 11/94 in group II had a low eGFR (<60mL/min/1.73m²). In group I, 14/17 had a normal eGFR after four years, including 11/12 who had AKI following snakebite, and the 3/17 with a low eGFR on review had CKD or co-morbidities for CKD. In group II, 10/11 had a normal eGFR after one year, including all nine patients with AKI following snakebite, and the one patient with a low eGFR on review had CKD. Fifty patients (25%) in group I and 43 (26%) in group II had a high urinary ACR on review, all but two in each group had microalbuminuria. Multivariate logistic regression showed in group I that only comorbidities for CKD were associated with high urinary ACR, and in group II comorbidities for CKD, snakebite associated AKI and snake type were associated with high urinary ACR. All nine patients from both groups with a low eGFR (CKD stages 3-5) had CKD prior to the snakebite or treatment for hypertension or diabetes.

CONCLUSION

There was no significant association between snakebite-associated AKI and CKD in patients followed up from a snakebite cohort post-bite. Microalbuminuria was common in these patients but likely associated with hypertension, diabetes mellitus and CINAC in this rural farming population.

Effects of cilostazol, a Phosphodiesterase-3 inhibitor, on kidney function and redox imbalance in acute kidney injury caused by Bothrops alternatus venom

The mechanisms of pathogenesis of acute kidney injury (AKI) in snakebites is multifactorial and involves hemodynamic disturbances, with release of free radical causing cytotoxic effects. The phosphodiesterase-3 (PDE3) inhibitor, Cilostazol, has been reported to provide protection against renal oxidative stress.

OBJECTIVE

We evaluated the protective effects of cilostazol against Bothrops alternatus snake venom (BaV)-induced nephrotoxicity.

METHODS

Wistar rat kidneys (n = 6, 260-300 g) were isolated and perfused with Krebs-Henseleit solution containing 6 g/100 mL of bovine serum albumin. After 30 min, the kidneys were perfused with BaV to a final concentration of 1 and 3 μg/mL, and subsequently evaluated for perfusion pressure (PP), renal vascular resistance (RVR), urinary flow (UF), glomerular filtration rate (GFR), and percentage of electrolyte tubular sodium and chloride transport (%TNa⁺, %TCl^-). Oxidative stress and renal histological analyses were performed.

RESULTS

BaV caused a reduction in all the evaluated renal parameters (PP, RVR, GFR, UF, %TNa⁺, and %TCl^-). Although only the effects on PP and UF were reversed with cilostazol treatment, the decrease in the malondialdehyde levels, without changes in glutathione levels, further reduced the venom-induced renal tissue changes.

CONCLUSION

Our data suggest that PDE3 is involved in BaV-induced nephrotoxicity, as cilostazol administration significantly ameliorated these effects.

The severity of acute kidney injury correlates with plasma venom levels in Bothrops atrox envenomings

The Brazilian Amazon has high rates of snakebite envenomings (SBEs), with ∼90% caused by Bothrops atrox. Envenomings by this species can trigger local and systemic effects, such as acute kidney injury (AKI). Our aim was to identify predictors of AKI in Bothrops SBEs in patients from Manaus, Western Brazilian Amazon. A total of 127 patients were enrolled, with a predominance of men between 16 and 45 years old from rural areas. Of the 127 patients, 38.6% developed AKI, with 61.2% presenting stage I, 34.7% presenting stage II and 4.1% presenting stage III severity. The age groups 0-10 years and ≥60 years presented a significantly higher frequency of AKI compared to the 11-40 years group. Moderate/severe edema in the affeccted limb was significantly associated with lower risk of AKI [p = 0.01; OR = 0.11 (95%CI 0.02-0.53)]. Nausea [p = 0.01; OR = 54.44 (95%CI = 3.26-909.27)] and high blood urea levels [p = 0.01; OR = 5.38 (95%CI = 2.12-13.66)] were risk factors for AKI. There was a significant positive correlation between circulating venom levels and the highest creatinine serum values during the hospital stay (p = 0.03) and with the difference between the maximum creatinine levels and the creatinine levels on admission (p = 0.02). A positive correlation between serum venom concentrations and creatinine levels suggests a direct or indirect dose-dependent participation of the venom toxins in the pathogenesis of AKI.

CCL-2 and CXCL-8: Potential Prognostic Biomarkers of Acute Kidney Injury after a Bothrops atrox Snakebite

In the Brazilian Amazon, the snake Bothrops atrox is the primary cause of snakebites. B. atrox (BaV) venom can cause systemic pathophysiological changes such as acute kidney injury (AKI), which leads to the production of chemokines and cytokines in response to the envenomation. These soluble immunological molecules act by modulating the inflammatory response; however, the mechanisms associated with the development of AKI are still poorly understood. Here, we characterize the profile of these soluble immunological molecules as possible predictive biomarkers of the development of AKI. The study involved 34 patients who had been victims of snakebites by Bothrops sp. These were categorized into two groups according to the development of AKI (AKI^(-)/AKI⁽⁺⁾), using healthy donors as the control (HD). Peripheral blood samples were collected at three-time points: before antivenom administration (T0) and at 24 and 48 hours after antivenom (T1 and T2, respectively). The soluble immunological molecules (CXCL-8, CCL-5, CXCL-9, CCL-2, CXCL-10, IL-6, TNF, IL-2, IL-10, IFN-γ, IL-4, and IL-17A) were quantified using cytometric bead array. Our results demonstrated an increase in CXCL-9, CXCL-10, IL-6, IL-2, IL-10, and IL-17A molecules in the groups of patients who suffered Bothrops snakebites (AKI^(-) and AKI⁽⁺⁾) before antivenom administration, when compared to HD. In the AKI⁽⁺⁾ group, levels of CXCL-8 and CCL-2 molecules were elevated on admission and progressively decreased during the clinical evolution of patients after antivenom administration. In addition, in the signature analysis, these were produced exclusively by the group AKI⁽⁺⁾ at T0. Thus, these chemokines may be related to the initiation and extension of AKI after envenomation by Bothrops and present themselves as two potential biomarkers of AKI at T0.

Histopathological Changes in the Liver, Heart and Kidneys Following Malayan Pit Viper (Calloselasma rhodostoma) Envenoming and the Neutralising Effects of Hemato Polyvalent Snake Antivenom

Calloselasma rhodostoma (Malayan pit viper) is a medically important snake species that is widely distributed across Southeast Asia. Systemic coagulopathy causing severe haemorrhage and local tissue injury is commonly observed following C. rhodostoma envenoming. However, nephrotoxicity and congestive heart failure were previously reported in a patient who had a long length of hospital stay. In this study, we determined the effect of C. rhodostoma envenoming on cardiovascular disturbances and the associated morphological changes in the liver, heart and kidneys using animal models. We also evaluated the efficacy of Hemato polyvalent antivenom (HPAV; Queen Saovabha Memorial Institute (QSMI) of the Thai Red Cross Society, Thailand) in neutralising the histopathological effects of C. rhodostoma venom. The intravenous (i.v.) administration of C. rhodostoma venom (1000 µg/kg) caused a rapid decrease in mean arterial pressure (MAP) followed by complete cardiac collapse in anaesthetized rats. Moreover, the intraperitoneal (i.p.) administration of C. rhodostoma venom (11.1 mg/kg; 3 × LD₅₀) for 24 h caused cellular lesions in the liver and heart tissues. C. rhodostoma venom also induced nephrotoxicity, as indicated by the presence of tubular injury, interstitial vascular congestion and inflammatory infiltration in the whole area of the kidney. The administration of HPAV, at manufacturer-recommended doses, 15 min prior to or after the addition of C. rhodostoma venom reduced the extent of the morphological changes in the liver, heart and kidneys. This study found that experimental C. rhodostoma envenoming induced cardiovascular disturbances, hepatotoxicity and nephrotoxicity. We also highlighted the potential broad utility of HPAV to neutralise the histopathological effects of C. rhodostoma venom. The early delivery of antivenom appears capable of preventing envenoming outcomes.

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.

Snake bite associated with acute kidney injury

Acute kidney injury (AKI) is a well-known life-threatening systemic effect of snake envenomation which commonly happens secondary to snake bites from families of Viperidae and Elapidae. Enzymatic toxins in snake venom result in injuries to all kidney cell types including glomerular, tubulo-interstitial and kidney vasculature. Pathogenesis of kidney injury due to snake envenomation includes ischaemia secondary to decreased kidney blood flow caused by systemic bleeding and vascular leakage, proteolytic degradation of the glomerular basement membrane by snake venom metalloproteinases (SVMPs), deposition of microthrombi in the kidney microvasculature (thrombotic microangiopathy), direct cytotoxic action of venom, systemic myotoxicity (rhabdomyolysis) and accumulation of large amounts of myoglobin in kidney tubules. Clinical features of AKI include fatigue, loss of appetite, headache, nausea, vomiting, oliguria and anuria. Monitoring of blood pressure, fluid balance, serum creatinine, blood urea nitrogen and serum electrolytes is useful in managing AKI induced by snake envenomation. Early initiation of anti-snake venom and early diagnosis of AKI are always desirable. Biomarkers which will help in early prediction of AKI are being explored, and current studies suggest that urinary clusterin, urinary neutrophil gelatinase-associated lipocalin, and serum cystatin C may play an important clinical role in the future. Apart from fluid and electrolyte management, kidney support including early and prompt initiation of kidney replacement therapy when indicated forms the bedrock in managing snake bite-associated AKI. Long-term follow-up is important because of chances of progression towards CKD.

A Biochemical and Pharmacological Characterization of Phospholipase A2 and Metalloproteinase Fractions from Eastern Russell's Viper (Daboia siamensis) Venom: Two Major Components Associated with Acute Kidney Injury

Acute kidney injury (AKI) following Eastern Russell's viper (Daboia siamensis) envenoming is a significant symptom in systemically envenomed victims. A number of venom components have been identified as causing the nephrotoxicity which leads to AKI. However, the precise mechanism of nephrotoxicity caused by these toxins is still unclear. In the present study, we purified two proteins from D. siamensis venom, namely RvPLA2 and RvMP. Protein identification using LCMS/MS confirmed the identity of RvPLA2 to be snake venom phospholipase A2 (SVPLA2) from Thai D. siamensis venom, whereas RvMP exhibited the presence of a factor X activator with two subunits. In vitro and in vivo pharmacological studies demonstrated myotoxicity and histopathological changes of kidney, heart, and spleen. RvPLA2 (3-10 µg/mL) caused inhibition of direct twitches of the chick biventer cervicis muscle preparation. After administration of RvPLA2 or RvMP (300 µg/kg, i.p.) for 24 h, diffuse glomerular congestion and tubular injury with minor loss of brush border were detected in envenomed mice. RvPLA2 and RvMP (300 µg/kg; i.p.) also induced congestion and tissue inflammation of heart muscle as well as diffuse congestion of mouse spleen. This study showed the significant roles of PLA2 and SVMP in snake bite envenoming caused by Thai D. siamensis and their similarities with observed clinical manifestations in envenomed victims. This study also indicated that there is a need to reevaluate the current treatment strategies for Thai D. siamensis envenoming, given the potential for irreversible nephrotoxicity.

Revisiting the acute kidney injury in Wistar rats experimentally envenomated wity Bothrops jararacussu venom

There is no consensus on whether serotherapy prevents acute kidney injury (AKI) and there is no pharmacotherapy to impede the disease. We aimed to elaborate an AKI model induced by the administration of Bothrops jararacussu (Bj) venom for preclinical studies. Male Wistar rats were randomly divided into 3 different groups: (1) Bj-IV: intravenous administration of 0.4 mg/kg Bj; (2) Bj-IP: intraperitoneal administration of 2.0 mg/kg Bj; (3) Bj-IM: intramuscular administration of 3.5 mg/kg Bj. For each corresponding control group, a 0.9% saline solution was administered. Kidneys, blood and urine samples were collected 24 or 72 h after administration of the Bj venom for renal function analysis. The IV- and IP-Bj groups presented a moderate tubular injury (score 3) and a time-dependent kidney dysfunction. In the Bj-IM group, renal tubular injury was aggravated (score 4) with collagen deposition and renal dysfunction was observed in the first 24 h: hyperfiltration, proteinuria, albuminuria and decreased fractional sodium excretion (FE_Na), regardless of the administered dose. Over time, the glomerular lesion was intensified, with a decrease in glomerular filtration rate (GFR; 67%), blood urea-nitrogen (BUN; 68%) and urine volume decrease (71%). Proteinuria and tubular function returned to control levels after 72 h. We attributed the pronounced kidney injury and reduced filtration function in the Bj-IM to the muscle damage provoked by the IM administration. We concluded that the Bj-IM is the best preclinical model of AKI with the monitoring of the progression of renal function in the periods of 24 and 72 h.

Urine proteomic analysis reveals alterations in heme/hemoglobin and aminopeptidase metabolism during Lonomia obliqua venom-induced acute kidney injury

AIMS

Accidental contact with the Lonomia obliqua caterpillar is a common event in southern Brazil. Envenomed victims present consumption coagulopathy, which can evolve to acute kidney injury (AKI). In the present study, we searched for AKI biomarkers and changes in molecular pathway signatures through urine proteomic analysis.

METHODOLOGY

Male Wistar rats were injected with L. obliqua venom (1.5 mg/kg, via s.c.) or 0.9 % NaCl and distributed into metabolic cages. After 24 h, urine was obtained, and the set of differentially regulated proteins was analyzed by MudPIT technology in an OrbiTRAP mass spectrometer.

RESULTS

L. obliqua venom leads to an increase in urine output and water and electrolyte excretion and to an increase in the albumin to creatine ratio in urine. The proteomic analysis revealed an up-regulation of tubular injury biomarkers, such as neutrophil-gelatinase associated lipocalin (NGAL) and cystatin C, in urine from envenomed rats. Several components related to the heme scavenging system were up-regulated or exclusively identified in urine from envenomed animals. There was an increase in urinary heme levels and hemoglobin subunits, hemopexin, haptoglobin, and biliverdin reductase. Similarly, kinin- and angiotensin-generating/degrading peptidases, such as kallikreins, neprilysin, plasmin, dipeptidyl peptidase IV, cathepsin D, kininogen, and neutral, basic, glutamyl, and acidic aminopeptidases, were also up-regulated in urine.

CONCLUSIONS

L. obliqua envenomation induced tubular and glomerular injury, probably involving heme/hemoglobin toxicity and an imbalance in the kinin/angiotensin generating/degrading system.

Chronic kidney failure following lancehead bite envenoming: a clinical report from the Amazon region

Background:

Snakebite envenoming can be a life-threatening condition, for which emergency care is essential. The Bothrops (lancehead) genus is responsible for most snakebite-related deaths and permanent loss of function in human victims in Latin America. Bothrops spp. venom is a complex mixture of different proteins that are known to cause local necrosis, coagulopathy, and acute kidney injury. However, the long-term effects of these viper envenomings have remained largely understudied.

Case presentation:

Here, we present a case report of a 46-years old female patient from Las Claritas, Venezuela, who was envenomed by a snake from the Bothrops genus. The patient was followed for a 10-year period, during which she presented oliguric renal failure, culminating in kidney failure 60 months after the envenoming.

Conclusion:

In Latin America, especially in Brazil, where there is a high prevalence of Bothrops envenoming, it may be relevant to establish long-term outpatient programs. This would reduce late adverse events, such as chronic kidney disease, and optimize public financial resources by avoiding hemodialysis and consequently kidney transplantation.

Acute kidney failure following severe viper envenomation: clinical, biological and ultrasonographic aspects

Background:

Acute kidney injury (AKI) is a frequent complication of snakebite envenomation, which is still little known in sub-Saharan Africa. This study aims to describe the clinical, biological and ultrasonographic aspects of AKI following severe snakebite envenomation managed in the intensive care unit.

Method:

A prospective observational survey was performed in Benin over a period of 18 months. All patients suffering severe snakebite envenomation (SBE) were included. The diagnosis of AKI was made using the KDIGO criteria. Kidney ultrasound exam was performed in all patients to assess internal bleeding and morphological and structural abnormalities of the kidneys.

Results:

Fifty-one cases of severe SBE were included. All patients presented inflammatory syndrome and showed abnormal WBCT whereas bleeding was found in 46 of them (90%). The median time to hospital presentation was three days. The majority of patients were male (M/F sex ratio = 1.55) and the median age was 26. Sixteen patients (31%) showed AKI according to the KDIGO criteria. Severe AKI (KDIGO stage 2 and 3) was observed in three patients, including one stage 2 and two stage 3. Kidney ultrasound revealed three cases of kidney capsular hematoma (6%), two cases of kidney hypertrophy (3%), three cases of kidney injury (4%), two stage 1 KDIGO and one stage 2 KDIGO. Only one patient benefited from hemodialysis. All patients showing AKI recovered without sequels. The median duration of hospital stays was four days. Seven patients died (14%) including four among the 16 AKI patients. Antivenom has been administered to 41 patients (80%). The comparison between patients without and with AKI did not show any significant difference except gender (p = 10^-2).

Conclusion:

AKI is a common complication of severe snakebite envenomation. Resulting from inflammatory and hemorrhagic disorders, AKI may prove to be a short-term life-threatening factor.

Development of a Treatment Protocol for Cobra (Naja naja) Bite Envenoming in Dogs

There is limited information on clinical profiles, treatment, and management aspects of Indian cobra (Naja naja) bite envenoming in dogs in Sri Lanka. Dogs with cobra bites presented to the Veterinary Teaching Hospital (VTH), University of Peradeniya, were prospectively studied over a period of 72 months; local and systemic clinical manifestations and hematological abnormalities were recorded. We studied 116 cobra bite envenomings in dogs. A grading system was established using a combination of anatomical site of fang marks, as well as local and systemic clinical manifestations. Accordingly, treatment strategies were established using Indian polyvalent antivenom (AVS). Pain and swelling at the bite site were major clinical signs observed, while neurotoxic manifestations (mydriasis, wheezing, and crackles) were detected in most dogs. Leukocytosis was observed in 78% of them. Statistical analysis revealed that the grading scores obtained were compatible to initiate AVS administration according to the severity. The minimum number required was 2 AVS vials (range 2-12). Almost 20% of the dogs developed wheezing, crackles, hypersalivation, restlessness, and dyspnea as adverse reactions to AVS treatment. Necrotic wounds on bitten anatomical sites developed in 19% of the dogs and 2.5% developed acute kidney injuries as a consequence of envenoming crisis. Despite treatment, 3% of dogs died. No dry bites were recorded.

Retrospective evaluation of acute kidney injury in dogs with pit viper envenomation (2008-2017): 56 cases

OBJECTIVES

To describe the clinicopathological characteristics of dogs that develop acute kidney injury (AKI) secondary to pit viper envenomation, and to describe the association between development of AKI and clinical course and outcome.

DESIGN

Retrospective study.

SETTING

University teaching hospital.

ANIMALS

Client-owned dogs treated with at least 1 vial of antivenom following pit viper envenomation and that had at least 2 plasma creatinine concentrations measured during the course of hospitalization.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Sixty-three dogs met the inclusion criteria. One was excluded due chronic kidney disease, and 6 were excluded due to nonsteroidal anti-inflammatory drug administration. Of the 56 dogs included in the study, 16 developed AKI (29%). Dogs with AKI received a significantly higher dose of antivenom, 8.7 ± 6.8 total vials versus dogs in the non-AKI group that received 4.2 ± 2.6 vials (P = 0.006). Dogs in the AKI group were significantly more tachycardic (P = 0.028), hypotensive (P = 0.002), had a higher shock index (P = 0.012), and were more likely to receive transfusions with packed red blood cells (P = 0.042) than dogs in the non-AKI group. No significant association was identified between the development of AKI and length of hospitalization. The only factors that were significantly associated with degree of severity of AKI included the receipt of blood transfusion (P = 0.006) and number of vials of antivenom administered (P = 0.03). The development of AKI was significantly associated with outcome (P < 0.001), with 5 of 16 (31%) dogs in the AKI group surviving to discharge, 7 of 16 (44%) dying, and 4 of 16 (25%) being euthanized versus 39 of 40 (98%) surviving to discharge in the non-AKI group and 1 of 40 (2%) dying in hospital.

CONCLUSION

Development of AKI in dogs following pit viper envenomation carries an increased risk of mortality that is associated with severity of shock at presentation and increased doses of antivenom administration.

Thrombotic microangiopathy due to Bothrops erythromelas: a case report in Northeast Brazil

Bothrops erythromelas are serpents that belong to the Viperidae family, which are the main species responsible for human snakebites in Ceara State, Northeast Brazil. Thrombotic microangiopathy (TMA) is an uncommon group of disorders characterized by microangiopathic hemolytic anemia (MAHA), thrombocytopenia and acute kidney injury (AKI), and occurrence after snakebites have been rarely reported. In this report, we described the case of a 57 year-old-man without comorbidities who was bitten by a Bothrops erythromelas on his right ankle. He presented with pain, edema and local bleeding. Symptomatology and laboratory tests were compatible with the diagnosis of TMA. He received specific antivenom and fluids replacement without any anaphylactic reaction. The conservative treatment was effective and there was no need for red blood cells transfusion or plasmapheresis. The aim of this report was to describe the first case of thrombotic microangiopathy following Bothrops erythromelas envenoming in the Northeast Brazil, providing insights about important mechanistic pathways of Bothrops snakebite-associated TMA and how to change the prognosis of the disease.

Clinical assessment and pathophysiology of Bothrops venom-related acute kidney injury: a scoping review

Bothrops are one of the most common medically important snakes found in Latin America. Its venom is predominantly hemotoxic and proteolytic, which means that local lesion (edema and redness) and hemorrhagic symptoms are recurrent in envenoming by this snake. Although hemorrhage is usually the major cause of death, snakebite-related acute kidney injury is another potentially fatal clinical complication that may lead to chronic kidney disease. The present review highlights the main studies on Bothrops venom-related acute kidney injury, including observational, cross-sectional, case-control and cohort human studies available up to December 2019. The following descriptors were used according to Medical Subject Headings (MeSH): on Medline/Pubmed and Google Scholar "acute kidney injury" or "kidney disease" and "Bothrops"; on Lilacs and SciELO "kidney disease" or "acute kidney injury" and "Bothrops". Newcastle-Ottawa quality assessment scale was used to appraise the quality of the cross-sectional and cohort studies included. The selection of more severe patients who looked for health care units and tertiary centers is a risk of bias. Due to the methodological heterogeneity of the studies, a critical analysis of the results was performed based on the hypothesis that the design of the included studies influences the incidence of acute kidney injury. Fifteen human studies (total participants 4624) were included according to stablished criteria. The coagulation abnormalities (hemorrhagic symptoms, abnormal fibrinogen and activated partial thromboplastin time) were associated with acute kidney injury in the most recent studies reported. The findings observed in this review provide up-to-date evidence about the acute kidney injury pathogenesis following Bothrops syndrome. Studies pointed out that coagulation abnormalities comprise the major pathway for acute kidney injury development. This review may improve patient management by primary healthcare providers, allowing earlier diagnosis and treatment of Bothrops venom-related acute kidney injury.

Kidney injury following envenoming by hump-nosed pit viper (Genus: Hypnale) in Sri Lanka: proven and probable cases

BACKGROUND

Hump-nosed pit vipers (Hypnale hypnale) are highly venomous snakes found in Sri Lanka and the Western Ghats region of India. They are the most common cause of venomous snakebites in Sri Lanka, mainly causing local envenoming leading to pain, swelling and necrosis. Systemic envenoming causing acute kidney injury and coagulopathy are more commonly recognized following their bites.

METHOD

A series of 465 patients with hump-nosed viper bites was prospectively studied over four years from January 2014. All patients were assessed and the data were collected by the principal investigator (primary data).

RESULTS

Forty-four (9.5%) patients developed acute kidney injury, of which 23 (5%) were proven cases and 21 (4.5%) were probable cases. Of the proven cases, 4 (17%) progressed to chronic kidney disease and 12 (52%) had thrombotic microangiopathy, from which 11 (48%) developed haemolytic uremic syndrome and 1 (4%) had thrombotic thrombocytopenic purpura. Twelve (52%) showed microangiopathic haemolysis and 15 (65%) had thrombocytopenia. Oliguria was observed in 10 (43%) whereas 7 (30%) each had anuria and normal urine output. Ten patients (43%) developed haematuria, from which 6 had microscopic haematuria and 4 had macroscopic haematuria. Proteinuria was observed in 8 (35%). Coagulopathy developed in 3 (13%) patients. In probable cases, 3 (14%) died due to complications of kidney injury.

CONCLUSION

A significant proportion of patients develop acute kidney injury following hump-nosed pit viper bite. Who will develop acute kidney injury or succumb to the venom is unpredictable. Reliable and accessible treatments are a critical unmet need.

Plasmapheresis for Pulmonary Hemorrhage Following Viperine Snakebite: A Case Report with Review of Literature

Introduction

Snakebites are one of the commonest occupational hazards in tropical countries and viperine bites are potential to cause systemic toxicity. Coagulopathies and acute kidney injury (AKI) have been documented and easily dealt with in past, but pulmonary hemorrhage has been rarely seen and plasmapheresis has shown promising result for the same. This case reports highlight the effective use of plasmapheresis for pulmonary hemorrhage post-snakebite.

Background

Viperine snakebite has been associated with high morbidity and mortality due to its toxic systemic envenomization. The important systemic manifestations are coagulopathy, neuromuscular paralysis, AKI, myotoxicity, and cardiovascular collapse. Antivenomization, renal replacement therapy, steroids, and other supportive care are considered to be the mainstay of treatment till date. Pulmonary hemorrhage has been an unusual manifestation of viper bite and rarely reported and steroids have been used in such scenario but with mixed results. Role of plasmapheresis has been documented in the management of snakebite but especially for hematological problems and in limb preservation/salvage strategies. The use of same, for pulmonary hemorrhage has not been studied yet. Here, we present a rare case of pulmonary hemorrhage along with renal failure following viper bite which was successfully treated with plasmapheresis. To the best of our knowledge, it is a rare presentation and has not been reported in the literature reviewed till date.

Case description

A previously healthy, 36-year-old man presented to our hospital 48 hours after a viper bite. He developed local as well systemic manifestations evident as hemolysis and renal failure. Gradually, he started having hemoptysis followed by respiratory failure requiring ventilatory support. CT chest done was s/o bilateral pulmonary hemorrhages correlating clinically with ongoing tracheal bleed. He had no other bleeding manifestations and had normal coagulation profile. He was initially treated with methylprednisolone therapy, but then did not show any improvement and finally plasmapheresis was done as rescue therapy. Following this, he had improvement in respiratory parameters and settling tracheal bleed with resolution of radiological changes. He was successfully weaned off from the ventilation and also his renal failure also improved with near normalization of pulmonary and renal functions.

Conclusion

This case highlights the unusual presentation of pulmonary hemorrhage in a patient with viperine bite with normal coagulation and was aggressively managed with plasmapheresis. Hence, plasmapheresis can be used as life-saving modality in patients with systemic envenomization post-viperine bit.

How to cite this article

Sampley S, Sakhuja V, Bhasin D, Singh K, Singh H. Plasmapheresis for Pulmonary Hemorrhage Following Viperine Snakebite: A Case Report with Review of Literature. Indian J Crit Care Med 2020;24(10):986-990.

Evaluation of the geographical utility of Eastern Russell's viper (Daboia siamensis) antivenom from Thailand and an assessment of its protective effects against venom-induced nephrotoxicity

BACKGROUND

Daboia siamensis (Eastern Russell's viper) is a medically important snake species found widely distributed across Southeast Asia. Envenomings by this species can result in systemic coagulopathy, local tissue injury and/or renal failure. While administration of specific antivenom is an effective treatment for Russell's viper envenomings, the availability of, and access to, geographically-appropriate antivenom remains problematic in many rural areas. In this study, we determined the binding and neutralizing capability of antivenoms manufactured by the Thai Red Cross in Thailand against D. siamensis venoms from four geographical locales: Myanmar, Taiwan, China and Thailand.

METHODOLOGY/PRINCIPLE FINDINGS

The D. siamensis monovalent antivenom displayed extensive recognition and binding to proteins found in D. siamensis venom, irrespective of the geographical origin of those venoms. Similar immunological characteristics were observed with the Hemato Polyvalent antivenom, which also uses D. siamensis venom as an immunogen, but binding levels were dramatically reduced when using comparator monovalent antivenoms manufactured against different snake species. A similar pattern was observed when investigating neutralization of coagulopathy, with the procoagulant action of all four geographical venom variants neutralized by both the D. siamensis monovalent and the Hemato Polyvalent antivenoms, while the comparator monovalent antivenoms were ineffective. These in vitro findings translated into therapeutic efficacy in vivo, as the D. siamensis monovalent antivenom was found to effectively protect against the lethal effects of all four geographical venom variants preclinically. Assessments of in vivo nephrotoxicity revealed that D. siamensis venom (700 μg/kg) significantly increased plasma creatinine and blood urea nitrogen levels in anaesthetised rats. The intravenous administration of D. siamensis monovalent antivenom at three times higher than the recommended scaled therapeutic dose, prior to and 1 h after the injection of venom, resulted in reduced levels of markers of nephrotoxicity and prevented renal morphological changes, although lower doses had no therapeutic effect.

CONCLUSIONS/SIGNIFICANCE

This study highlights the potential broad geographical utility of the Thai D. siamensis monovalent antivenom for treating envenomings by the Eastern Russell's viper. However, only the early delivery of high antivenom doses appears to be capable of preventing venom-induced nephrotoxicity.

Long-term Effects of Snake Envenoming

Long-term effects of envenoming compromise the quality of life of the survivors of snakebite. We searched MEDLINE (from 1946) and EMBASE (from 1947) until October 2018 for clinical literature on the long-term effects of snake envenoming using different combinations of search terms. We classified conditions that last or appear more than six weeks following envenoming as long term or delayed effects of envenoming. Of 257 records identified, 51 articles describe the long-term effects of snake envenoming and were reviewed. Disability due to amputations, deformities, contracture formation, and chronic ulceration, rarely with malignant change, have resulted from local necrosis due to bites mainly from African and Asian cobras, and Central and South American Pit-vipers. Progression of acute kidney injury into chronic renal failure in Russell's viper bites has been reported in several studies from India and Sri Lanka. Neuromuscular toxicity does not appear to result in long-term effects. Endocrine anomalies such as delayed manifestation of hypopituitarism following Russell's viper bites have been reported. Delayed psychological effects such as depressive symptoms, post-traumatic stress disorder and somatisation have been reported. Blindness due to primary and secondary effects of venom is a serious, debilitating effect. In general, the available studies have linked a clinical effect to a snakebite in retrospect, hence lacked accurate snake authentication, details of acute management and baseline data and are unable to provide a detailed picture of clinical epidemiology of the long-term effects of envenoming. In the future, it will be important to follow cohorts of snakebite patients for a longer period of time to understand the true prevalence, severity, clinical progression and risk factors of long-term effects of snake envenoming.

Acute Kidney Injury Induced by Bothrops Venom: Insights into the Pathogenic Mechanisms

Acute kidney injury (AKI) following snakebite is common in developing countries and Bothrops genus is the main group of snakes in Latin America. To evaluate the pathogenic mechanisms associated with Bothrops venom nephrotoxicity, we assessed urinary and blood samples of patients after hospital admission resulting from Bothrops snakebite in a prospective cohort study in Northeast Brazil. Urinary and blood samples were evaluated during hospital stay in 63 consenting patients, divided into AKI and No-AKI groups according to the KDIGO criteria. The AKI group showed higher levels of urinary MCP-1 (Urinary monocyte chemotactic protein-1) (median 547.5 vs. 274.1 pg/mgCr; p = 0.02) and urinary NGAL (Neutrophil gelatinase-associated lipocalin) (median 21.28 vs. 12.73 ng/mgCr; p = 0.03). Risk factors for AKI included lower serum sodium and hemoglobin levels, proteinuria and aPTT (Activated Partial Thromboplastin Time) on admission and disclosed lower serum sodium (p = 0.01, OR = 0.73, 95% CI: 0.57–0.94) and aPTT (p = 0.031, OR = 26.27, 95% CI: 1.34–512.11) levels as independent factors associated with AKI. Proteinuria showed a positive correlation with uMCP-1 (r = 0.70, p < 0.0001) and uNGAL (r = 0.47, p = 0.001). FE_Na (Fractional Excretion of sodium) correlated with uMCP-1 (r = 0.47, P = 0.001) and uNGAL (r = 0.56, p < 0.0001). sCr (serum Creatinine) showed a better performance to predict AKI (AUC = 0.85) in comparison with new biomarkers. FE_K showed fair accuracy in predicting AKI (AUC = 0.92). Coagulation abnormality was strongly associated with Bothrops venom-related AKI. Urinary NGAL and MCP-1 were good biomarkers in predicting AKI; however, sCr remained the best biomarker. FE_K (Fractional Excretion of potassium) emerged as another diagnostic tool to predict early AKI. Positive correlations between uNGAL and uMCP-1 with proteinuria and FE_Na may signal glomerular and tubular injury. Defects in urinary concentrations highlighted asymptomatic abnormalities, which deserve further study.

Systemic alterations induced by phospholipase A2 , BmooTX-I, isolated from Bothrops moojeni snake venom

Ophidic accidents are among the problems of public health in Brazil. The components from bothropic venom are responsible for many systemic clinical complications resulting from envenomation. The present work aimed to analyse the systemic changes induced in mice after intraperitoneal administration of BmooTX-I, a myotoxic acidic phospholipase A₂ isolated from Bothrops moojeni venom. Urinalysis was performed and the following plasma biochemical markers were documented: urea, creatinine and uric acid (renal function); glucose and amylase (pancreatic function); alanine aminotransferase, alkaline phosphatase and gamma-GT (intra- and extrahepatic function); creatine kinase and enzymatic lactate (muscle function). Our results showed that after the intraperitoneal injection of BmooTX-I the urine of these animals showed glycosuria, proteinuria, haematuria, bacteriuria, bilirubinuria, polyuria and nitrite. The plasma biochemical analysis showed alterations in levels of urea, creatinine and uric acid. Amylase concentration was not altered significantly, but the plasma glucose increased significantly compared to controls. The plasma levels of alanine aminotransferase and alkaline phosphatase decreased and increased, respectively, in these same animals. On the other hand, the plasma γGT concentration did not undergo significant modification compared to the control group. The plasma concentration of CK increased, while the enzymatic lactate concentration decreased after the injection of the BmooTX-I. Therefore, in mice BmooTX-I is capable of causing systemic alterations which manifest as renal, muscular, hepatic and pancreatic impairment.

Ameliorating effect of Alstonia scholaris L. bark extract on histopathological changes following viper envenomation in animal models

•

In the present paper, the histopathological changes of liver and kidney tissues associated with Vipera russelli envenomation and systemic venom neutralization potential of aqueous Alstonia scholaris Linn bark extract in animal models has been discussed.

•

Histological alterations observed in liver sections of venom treated groups were mainly pyknosis, karyorrhexis, cytoplasmic vacuolation, necrosis, fatty changes and hepatocytes atrophy.

•

Histological changes in venom treated kidney tissues were cell damage, peritubular congestion, degenerating changes in the proximal tubules in the form of cytoplasmic vacuolations, partially destroyed bowman’s capillaries with dilated Bowman’s space after staining with haematoxylin and eosin.

•

Both Antivenom and Alstonia scholaris Linn extract could significantly reduce the venom induced histological as well as biochemical changes (serum AST,ALT and creatinine) in the affected tissues.

Objectives

The primary symptoms associated with snake envenomation are both systemic and local. The local symptoms are characterized by pain, swelling, haemorrhage and myonecrosis at the site of bite. The present study investigates the ameliorating effect of the aqueous bark extract of Alstonia scholaris bark on viper venom induced histopathological and biochemical changes in liver and kidney of swiss albino mice models.

Methods & materials

Swiss albino mice (20 ± 2)g were treated with sublethal doses(0.5 μg and 1 μg) of Vipera russelli venom(VRV) intraperitonially The following groups were assigned in the study-Group I(saline control); Group II & III(Venom treated-0.5 μg ie ¼ LD50 and 1 μg ie 1/2 LD50) and Group IV &V(Venom-0.5 μg and 1 μg respectively incubated with Aqueous Alstonia scholaris (AAS) extract; 200 mg/kg bw) and Group VI (Antivenom serum (AVS) (2 mg/ml) followed by 1 μg Vipera russelli venom (VRV). The animals were sacrificed and their organs were immersed in Bouin's fixative for 24 h and stained with haematoxylin/eosin and observed under the microscope. The serum samples were collected from the animals and tested for serum Alanine transaminase (ALT) and Aspartate transaminases (AST) following the method of Reitman & Frankel(1957) and serum creatinine.

Results

The histological alterations observed in Group II and III liver sections were mainly pyknosis, karyorrhexis, cytoplasmic vacuolation, necrosis, fatty changes and hepatocytes atrophy. Sinusoidal dilatation, amyloidosis, portal vein thrombosis which was significantly reduced by AAS extract in Groups IV and V. A venom dose of 1 μg induced tubular cell acidophilia indicating cell damage, peritubular congestion, degenerating changes in the proximal tubules in the form of cytoplasmic vacuolations, partially destroyed bowman’s capillaries with dilated Bowman’s space in Group III that was significantly reduced by Aqueous Alstonia scholaris (AAS) (200 mg/kg bw) extract in Groups IV and Group V.AVS gave significant protection against venom induced action in Group VI.

Conclusion

The present paper thus highlights the histopathological changes associated with Vipera russelli venom and systemic venom neutralization potential of Aqueous Alstonia scholaris (AAS) in animal models.

Predicting acute renal failure in Bothrops snakebite patients in a tertiary reference center, Western Brazilian Amazon

Acute Kidney Injury (AKI) is the main systemic complication and cause of death in viperid envenomation. Although there are hypotheses for the development of AKI, the mechanisms involved are still not established. The aim of this study was to evaluate the clinical-laboratorial-epidemiological factors associated with AKI in victims of Bothrops sp envenomation. This is an observational study carried out at the Fundação de Medicina Tropical Dr. Heitor Vieira Dourado. AKI was defined according to the guidelines of the Acute Kidney Injury Network (AKIN). Among the 186 patients evaluated, AKI was observed in 24 (12.9%) after 48 hours of admission. Stage I was present in 17 (70.8%) patients, II in 3 (12.5%) and III in 4 (16.7%). Epidemiological characterization showed predominance of men, occurrence in rural areas, aged between 16–60 years, feet as the most affected anatomical region, and time to medical assistance less than 3 hours. Hypertension and diabetes were the comorbidities identified. Most of the accidents were classified as moderate, and clinical manifestations included severe pain, mild edema, local bleeding and headache. Laboratory results showed blood uncoagulability, hypofibrinogenemia, leukocytosis, increase of creatine kinase, and high lactate dehydrogenase levels. Multivariate analysis showed an association with high LDH levels [AOR = 1.01 (95% CI = 1.01–1.01, p<0.002)], local bleeding [AOR = 0.13 (95%CI = 0.027–0.59, p<0.009)], and the presence of comorbidities [AOR = 60.96 (95%CI = 9.69–383.30; p<0.000)]. Herein, laboratory markers such as high LDH levels along with local bleeding and comorbidities may aid in the diagnosis of AKI.

Long-term health complications following snake envenoming

Background

Snakebite is an important public health problem in tropical regions of the world. Although devastating effects of envenoming such as kidney failure, tissue necrosis, bleeding diathesis, and neurotoxicity are well known in the acute stage following a snakebite, the long-term effects of snake envenoming have not been adequately studied.

Materials and methods

A population-based study was conducted among 8707 residents in a rural district in Sri Lanka to assess the long-term sequelae following snakebite. Health-related complaints that snakebite victims had developed immediately or within 4 weeks of the bite and persisted for more than 3 months, were assessed by interviewer-administered questionnaire and in-depth interviews, and further evaluated by physical examination and relevant investigations.

Results

Of the 816 participants who were identified as ever snakebite victims, 112 (13.7%) presented with at least one snakebite-related long-term health complication. Among them, “migraine-like-syndrome” characterized by headache vertigo, and photosensitivity to sunlight was found in 46 (5.6%); musculoskeletal disorders such as pain, local swelling, muscle weakness, deformities, contractures, and amputations were found in 26 (3.2%); visual impairment in 21 (2.6%); acute kidney injury in 4 (0.5%); skin blisters at the bite site in 5 (0.6%); psychological distress in 2 (0.2%); hemiplegia in 1 (0.1%); right-side facial nerve palsy in 1 (0.1%); paresthesia over bite site in 1 (0.1%); generalized shivering in 1 (0.1%); and chronic nonhealing ulcer in 1 (0.1%). Interestingly, 31 (3.8%) reported nonspecific somatic symptoms such as abdominal colic, chest tightness, wheezing, receding gums, excessive hair loss, and lassitude with body aches following the bite. The average duration of symptoms since snakebite was 12.7 years (SD=11.7).

Conclusion

This study highlights that a significant proportion of snakebite victims suffer disabling chronic health sequelae. There is a need to place systems to address these unmet health needs.

Venom proteomics and antivenom neutralization for the Chinese eastern Russell's viper, Daboia siamensis from Guangxi and Taiwan

The eastern Russell's viper (Daboia siamensis) causes primarily hemotoxic envenomation. Applying shotgun proteomic approach, the present study unveiled the protein complexity and geographical variation of eastern D. siamensis venoms originated from Guangxi and Taiwan. The snake venoms from the two geographical locales shared comparable expression of major proteins notwithstanding variability in their toxin proteoforms. More than 90% of total venom proteins belong to the toxin families of Kunitz-type serine protease inhibitor, phospholipase A2, C-type lectin/lectin-like protein, serine protease and metalloproteinase. Daboia siamensis Monovalent Antivenom produced in Taiwan (DsMAV-Taiwan) was immunoreactive toward the Guangxi D. siamensis venom, and effectively neutralized the venom lethality at a potency of 1.41 mg venom per ml antivenom. This was corroborated by the antivenom effective neutralization against the venom procoagulant (ED = 0.044 ± 0.002 µl, 2.03 ± 0.12 mg/ml) and hemorrhagic (ED50 = 0.871 ± 0.159 µl, 7.85 ± 3.70 mg/ml) effects. The hetero-specific Chinese pit viper antivenoms i.e. Deinagkistrodon acutus Monovalent Antivenom and Gloydius brevicaudus Monovalent Antivenom showed negligible immunoreactivity and poor neutralization against the Guangxi D. siamensis venom. The findings suggest the need for improving treatment of D. siamensis envenomation in the region through the production and the use of appropriate antivenom.

Non-neurotoxic activity of Malayan krait (Bungarus candidus) venom from Thailand

Background

Envenoming by kraits (genus Bungarus) is a medically significant issue in South Asia and Southeast Asia. Malayan krait (Bungarus candidus) venom is known to contain highly potent neurotoxins. In recent years, there have been reports on the non-neurotoxic activities of krait venom that include myotoxicity and nephrotoxicity. However, research on such non-neurotoxicity activities of Malayan krait venom is extremely limited. Thus, the aim of the present study was to determine the myotoxic, cytotoxic and nephrotoxic activities of B. candidus venoms from northeastern (BC-NE) and southern (BC-S) Thailand in experimentally envenomed rats.

Methods

Rats were administered Malayan krait (BC-NE or BC-S) venom (50 μg/kg, i.m.) or 0.9% NaCl solution (50 μL, i.m.) into the right hind limb. The animals were sacrificed 3, 6 and 24 h after venom administration. The right gastrocnemius muscle and both kidneys were collected for histopathological analysis. Blood samples were also taken for determination of creatine kinase (CK) and lactate dehydrogenase (LDH) levels. The human embryonic kidney cell line (HEK-293) was used in a cell proliferation assay to determine cytotoxic activity.

Results

Administration of BC-NE or BC-S venom (50 μg/kg, i.m.) caused time-dependent myotoxicity, characterized by an elevation of CK and LDH levels. Histopathological examination of skeletal muscle displayed marked muscle necrosis and myofiber disintegration 24 h following venom administration. Both Malayan krait venoms also induced extensive renal tubular injury with glomerular and interstitial congestion in rats. BC-NE and BC-S venoms (100–0.2 μg/mL) caused concentration-dependent cytotoxicity on the HEK-293 cell line. However, BC-NE venom (IC₅₀ = 8 ± 1 μg/mL; at 24 h incubation; n = 4) was found to be significantly more cytotoxic than BC-S venom (IC₅₀ = 15 ± 2 μg/mL; at 24 h incubation; n = 4). In addition, the PLA₂ activity of BC-NE venom was significantly higher than that of BC-S venom.

Conclusions

This study found that Malayan krait venoms from both populations possess myotoxic, cytotoxic and nephrotoxic activities. These findings may aid in clinical diagnosis and treatment of envenomed patients in the future.

Melatonin inhibits snake venom and antivenom induced oxidative stress and augments treatment efficacy

Snakebite is a neglected health hazard. Its patho-physiology has largely been focused on systemic and local toxicities; whereas, venom and antivenom induced oxidative stress has long been ignored. Antivenom therapy although neutralizes venom lethality and saves many lives, remains ineffective against oxidative stress. This prompted us to complement antivenom with an antioxidant molecule melatonin that would protect against oxidative stress and increase the efficacy of the existing snakebite therapy. Here we show that D. russelli and E. carinatus venoms induce strong oxidative stress that persists even after antivenom administration in mice model. Additionally, antivenoms also induce oxidative stress. Polyvalent antivenom induce more oxidative stress than monovalent antivenom. Strikingly, antivenom and melatonin together not only inhibit venom and antivenom induced oxidative stress but also significantly reduce the neutralizing antivenom dose. This study provides a therapeutic potential for enhancing the existing snakebite therapy. The combined treatment of antivenom+melatonin would prevent the upsurge of oxidative stress as well as minimize the antivenom load. Thus the investigation offers immense scope for physicians and toxinologists to reinvestigate, design new strategies and think beyond the conventional mode of antivenom therapy.

Clinical and laboratory parameters associated with acute kidney injury in patients with snakebite envenomation: a prospective observational study from Myanmar

Background

Snakebite-related acute kidney injury (AKI) is a common community-acquired AKI in tropical countries leading to death and disability. The aims of this study were to (1) determine the occurrence of snakebite-related AKI, (2) assess factors at presentation that are associated with snakebite-related AKI, and (3) determine the outcomes of patients with snakebite-related AKI.

Methods

We conducted a prospective observational study of patients with snake envenomation at the three academic tertiary care hospitals in Yangon, Myanmar between March 2015 and June 2016. Patient data including baseline characteristics, clinical and laboratory findings, hospital management, and outcomes were recorded in a case report form. A stepwise multivariate logistic regression analysis using a backward selection method determined independent factors significantly associated with AKI.

Results

AKI was observed in 140 patients (54.3%), the majority of whom were AKI stage III (110 patients, 78.6%). AKI occurred at presentation and developed during hospitalization in 88 (62.9%) and 52 patients (37.1%), respectively. Twenty-seven patients died (19.3%), and 69 patients (49.3%) required dialysis. On multivariate logistic regression analysis, (1) snakebites from the Viperidae family (odds ratio [OR]: 9.65, 95% confidence interval [CI]: 2.42–38.44; p = 0.001), (2) WBC >10 × 10³ cells/μL (OR: 3.55, 95% CI: 1.35–9.34; p = 0.010), (3) overt disseminated intravascular coagulation (OR: 2.23, 95% CI: 1.02–4.89; p = 0.045), (4) serum creatine kinase >500 IU/L (OR: 4.06, 95% CI: 1.71–9.63; p = 0.001), (5) serum sodium <135 mmol/L (OR: 4.37, 95% CI: 2.04–9.38; p < 0.001), (6) presence of microscopic hematuria (OR: 3.60, 95% CI: 1.45–8.91; p = 0.006), and (7) duration from snakebite to receiving antivenom ≥2 h (OR: 3.73, 95% CI: 1.48–9.37; p = 0.005) were independently associated with AKI. Patients bitten by Viperidae with normal renal function who had serum sodium <135 mmol/L had a significantly higher urine sodium-to-creatinine ratio than those with serum sodium ≥135 mmol/L (p < 0.001).

Conclusions

Identifying factors associated with snakebite-related AKI might help clinicians to be aware of snakebite patients who are at risk of AKI, particularly patients who demonstrate renal tubular dysfunction after Viperidae bites.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-017-0510-0) contains supplementary material, which is available to authorized users.

Acute effect of Russell’s viper (Daboia siamensis) venom on renal tubular handling of sodium in isolated rabbit kidney

Background: The common complication in cases of poisoning by Russell’s viper (Daboia siamensis) venom (RVV) is acute renal failure, but the pathogenesis involved in the alteration of kidney function is still not well understood.

Objective: To clarify the role of RVV in the pathogenesis of renal damage, the present study examines the functional short-term alterations acutely induced by RVV in isolated perfused rabbit kidney.

Methods: Effects of RVV on renal tubular handling of sodium including mean perfusion pressure (PP), the renalvascular resistance (RVR), the glomerular filtration rate (GFR), the urinary flow (V) and osmolar clearance (Cosm) were studied in two groups of isolated perfused rabbit kidneys; each group had four isolated rabbit kidneys. RVV was added to the perfusion system to obtain the final concentration of 10 ⃞g/ml.

Results: Immediate decreases in PP and RVR caused by the venom were significantly apparent (p < 0.05) in the first 15 min after RVV administration. A gradual rise in both PP and RVR occurred 15 min after the initial reduction of the first phase, but its remained below pretreatment values. The GFR, V, and Cosm decreased significantly throughout experiments after venom perfusion (p < 0.05). The total fractional sodium excretion increased significantly after venom perfusion throughout experiments, while significant reductions (p < 0.05) of renal tubular handling of sodium were apparent for proximal absolute reabsorption of sodium and proximal fractional reabsorption of sodium including marked reductions of distal absolute reabsorption of sodium and distal fractional reabsorption of sodium of the venom treated kidney. Optical microscopy of treated kidney tissue showed acute tubular necrosis at the end of experiment.

Conclusion: The present study suggests that an administration of RVV in the isolated rabbit kidney causes direct acute nephrotoxicity and acute alterations of main functional parameters that are probably mediated by either the direct action of venom components or an indirect effect from vasoactive mediators released from renal cells of the RVV-treated kidney.

Clinical and Pharmacological Investigation of Myotoxicity in Sri Lankan Russell's Viper (Daboia russelii) Envenoming

BACKGROUND

Sri Lankan Russell's viper (Daboia russelii) envenoming is reported to cause myotoxicity and neurotoxicity, which are different to the effects of envenoming by most other populations of Russell's vipers. This study aimed to investigate evidence of myotoxicity in Russell's viper envenoming, response to antivenom and the toxins responsible for myotoxicity.

METHODOLOGY AND FINDINGS

Clinical features of myotoxicity were assessed in authenticated Russell's viper bite patients admitted to a Sri Lankan teaching hospital. Toxins were isolated using high-performance liquid chromatography. In-vitro myotoxicity of the venom and toxins was investigated in chick biventer nerve-muscle preparations. Of 245 enrolled patients, 177 (72.2%) had local myalgia and 173 (70.6%) had local muscle tenderness. Generalized myalgia and muscle tenderness were present in 35 (14.2%) and 29 (11.8%) patients, respectively. Thirty-seven patients had high (>300 U/l) serum creatine kinase (CK) concentrations in samples 24h post-bite (median: 666 U/l; maximum: 1066 U/l). Peak venom and 24h CK concentrations were not associated (Spearman's correlation; p = 0.48). The 24h CK concentrations differed in patients without myotoxicity (median 58 U/l), compared to those with local (137 U/l) and generalised signs/symptoms of myotoxicity (107 U/l; p = 0.049). Venom caused concentration-dependent inhibition of direct twitches in the chick biventer cervicis nerve-muscle preparation, without completely abolishing direct twitches after 3 h even at 80 μg/ml. Indian polyvalent antivenom did not prevent in-vitro myotoxicity at recommended concentrations. Two phospholipase A2 toxins with molecular weights of 13kDa, U1-viperitoxin-Dr1a (19.2% of venom) and U1-viperitoxin-Dr1b (22.7% of venom), concentration dependently inhibited direct twitches in the chick biventer cervicis nerve-muscle preparation. At 3 μM, U1-viperitoxin-Dr1a abolished twitches, while U1-viperitoxin-Dr1b caused 70% inhibition of twitch force after 3h. Removal of both toxins from whole venom resulted in no in-vitro myotoxicity.

CONCLUSION

The study shows that myotoxicity in Sri Lankan Russell's viper envenoming is mild and non-life threatening, and due to two PLA2 toxins with weak myotoxic properties.

Multisystem failure and death due to extensive hemorrhaging and brain herniation subsequent to a bite by an unidentified snake

Background

Snakebites cause considerable morbidity and mortality in tropical and subtropical countries even though existing treatment methods can prevent most deaths if presentation occurs early to hospitals. Envenomation by unidentified snakes is common in central Sri Lanka. Management of such patients is challenging especially if presentation is late.

Case presentation

Here, we report a case of a 52-year-old man from central Sri Lanka who presented late after being bitten by an unidentified snake. He developed `severe coagulopathy, neurotoxicity, acute kidney injury, and rhabdomyolysis. Subsequently, despite of treatment, he died due to extensive hemorrhaging in many organs. A large intracranial hemorrhage lead to fatal brain herniation.

Conclusions

Envenomation by some snake species can severely affect multiple body systems and give rise to fatal brain hemorrhages and brain herniation. Considering the known effects of local snake venom, the responsible species is likely to be Russell’s viper (Daboia russelii). We recommend some simple measures to reduce the chances of such deaths in the future.