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

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.

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.

Epidemiological, clinical and hematobiochemical studies on hemotoxic snakebite in bovines

Snakebite is a conflict between venomous snakes and humans as well as livestock and considered as neglected tropical disease. The present study aimed to investigate the hospital prevalence, clinical and hemato-biochemical aspects of hemotoxic snakebite in bovines. The overall hospital prevalence of hemotoxic snakebite in bovines was found to be 0.93%. Highest prevalence of hemotoxic snakebite in bovines was observed in August month during monsoon season in female bovines with higher cases in buffaloes. The highest occurrence was reported in native Marathwadi buffalo, non-descript and Deoni cattle of > 4 years and 1-4 years age group in forelimbs and hindlimbs during morning and evening hours. Ascending swelling over limbs extending upward and lameness in case of bite on limbs while asymmetrical swelling in case of bite over face, occasional signs of bleeding like melena, hematuria, epistaxis and bleeding from the site of bite were the prominent clinical signs observed in hemotoxic snakebite affected bovines. Highly significant increase in heart rate and respiration rate, while decrease in rumen motility was observed in snakebite affected bovines. Hemato-biochemial analysis showed highly significant increase in leukocyte count, erythrocyte count and PCV, significant increase in granulocyte and monocyte count, highly significant decrease in platelet count while increase in capillary blood clotting time, bilirubin, blood urea nitrogen, creatinine, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and creatine kinase levels compared to healthy bovines.

Potential economic and clinical implications of improving access to snake antivenom in five ASEAN countries: A cost-effectiveness analysis

Background

Despite domestic production of antivenoms in the Association of Southeast Asian Nations (ASEAN) countries, not all victims with snakebite envenomings indicated for antivenom received the appropriate or adequate effective dose of antivenom due to insufficient supply and inadequate access to antivenoms. We aimed to conduct a cost-effectiveness analysis to project the potential economic and clinical impact of improving access to antivenoms when all snakebite envenomings in ASEAN countries were hypothetically treated with geographically appropriate antivenoms.

Methodology

Using a decision analytic model with input parameters from published literature, local data, and expert opinion, we projected the impact of “full access” (100%) to antivenom, compared to “current access” in five most impacted ASEAN countries, including Indonesia (10%), Philippines (26%), Vietnam (37%), Lao PDR (4%), and Myanmar (64%), from a societal perspective with a lifetime time horizon. Sensitivity analyses were performed.

Principal findings

In base-case analyses, full access compared to current access to snake antivenom in the five countries resulted in a total of 9,362 deaths averted (-59%), 230,075 disability-adjusted life years (DALYs) averted (-59%), and cost savings of 1.3 billion USD (-53%). Incremental cost-effectiveness ratios (ICERs) of improving access to antivenom found higher outcomes but lower costs in all countries. Probabilistic sensitivity analyses of 1,000 iterations found that 98.1–100% of ICERs were cost-saving.

Conclusion/Significance

Improving access to snake antivenom will result in cost-saving for ASEAN countries. Our findings emphasized the importance of further strengthening regional cooperation, investment, and funding to improve the situation of snakebite victims in ASEAN countries.

In the Association of Southeast Asian Nations (ASEAN) countries, it was estimated that annually there were 242,648 snakebite victims in ASEAN of which 15,909 victims were dead. Despite domestic production of antivenoms in ASEAN countries, not all victims with snakebite envenomings indicated for antivenom received the appropriate or adequate effective dose of antivenom due to insufficient supply and inadequate access to antivenoms. Especially in Indonesia, Philippines, Vietnam, Lao PDR, and Myanmar, where 4–64% of victims who needed antivenoms were treated with antivenoms. We conducted a cost-effectiveness analysis to project the potential economic and clinical impact of improving access to antivenoms when all victims with snakebite envenomings in the five most impacted ASEAN countries were hypothetically treated with geographically appropriate antivenoms. Improving access to snake antivenom to the full level of access compared to the current level in the five ASEAN countries resulted in a total of 9,362 deaths averted (-59%), 230,075 disability-adjusted life years (DALYs) averted (-59%), and cost savings of 1.3 billion USD (-53%). Our study demonstrated improving access to snake antivenom from the current to the full level of access in ASEAN countries is a cost-saving strategy. Our findings emphasized the importance of further strengthening regional cooperation, investment, and funding to improve the situation of snakebite victims in ASEAN countries to reach the ultimate goal where all victims with snakebite envenoming needing antivenom adequately received the geographically appropriate antivenoms.

Snakebite Associated Thrombotic Microangiopathy and Recommendations for Clinical Practice

Snakebite is a significant and under-resourced global public health issue. Snake venoms cause a variety of potentially fatal clinical toxin syndromes, including venom-induced consumption coagulopathy (VICC) which is associated with major haemorrhage. A subset of patients with VICC develop a thrombotic microangiopathy (TMA). This article reviews recent evidence regarding snakebite-associated TMA and its epidemiology, diagnosis, outcomes, and effectiveness of interventions including antivenom and therapeutic plasma-exchange. Snakebite-associated TMA presents with microangiopathic haemolytic anaemia (evidenced by schistocytes on the blood film), thrombocytopenia in almost all cases, and a spectrum of acute kidney injury (AKI). A proportion of patients require dialysis, most survive and achieve dialysis free survival. There is no evidence that antivenom prevents TMA specifically, but early antivenom remains the mainstay of treatment for snake envenoming. There is no evidence for therapeutic plasma-exchange being effective. We propose diagnostic criteria for snakebite-associated TMA as anaemia with >1.0% schistocytes on blood film examination, together with absolute thrombocytopenia (<150 × 10⁹/L) or a relative decrease in platelet count of >25% from baseline. Patients are at risk of long-term chronic kidney disease and long term follow up is recommended.

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.

Evaluation of Urinary Clusterin and Cystatin B as Biomarkers for Renal Injury in Dogs Envenomated by the European Adder (Vipera berus)

Dogs are commonly bitten by the European adder (Vipera berus) but studies investigating the effects of envenomation are limited. Snakebite-related kidney injury is reported in dogs but diagnosis of acute kidney injury (AKI) might be limited by the insensitivity of routinely used renal function biomarkers. The aim of this study was to evaluate novel biomarkers of renal injury (urinary cystatin B and urinary clusterin) and biomarkers of renal function (serum creatinine and serum symmetric dimethylarginine), and urine protein to creatinine ratio in dogs envenomated by V. berus. Biomarkers were measured at presentation (T1), 12 hours (T2), 24 hours (T3), 36 hours (T4), and 14 days (T5) after snakebite and compared to a group of healthy control dogs. A secondary aim was to investigate the association between biomarker concentrations and severity of clinical signs of envenomation using a snakebite severity score (SSS). Urinary cystatin B concentrations were significantly higher at all timepoints in envenomated dogs compared to controls (P < .010), except for T5 (P = .222). Absolute urinary clusterin concentrations were not significantly different to controls at any timepoint. Compared to controls, serum creatinine and serum symmetric dimethylarginine concentrations were significantly lower in envenomated dogs at T1-T4 (P < .036) and T2-T4 (P < .036), respectively. Urine protein to creatinine ratio was higher in envenomated dogs compared to controls at T2 and T3. Urinary cystatin B concentrations at T1 were correlated with SSS (Spearman's ρ = 0.690, P < .001). The increased urinary cystatin B concentrations observed in dogs envenomated by V. berus in comparison to controls may indicate renal tubular injury in these patients.

Role of endothelial biomarkers in predicting acute kidney injury in Bothrops envenoming

Acute kidney injury (AKI) is a frequent and potentially fatal complication of snakebites. In the setting of snakebites, endothelial biomarkers may be used to predict disease severity and can play a major role in AKI pathophysiology. The aim of this study was to investigate the potential role of endothelial biomarkers in predicting AKI in Bothrops envenoming. Therefore, blood and urine samples were collected from 26 patients admitted to the emergency department after Bothrops envenoming at 3 different post-bite points in time: on admission (up to 8 h post-bite), 12-16 h, and 24-28 h post-bite, to investigate the time course of endothelial biomarkers in AKI following Bothrops snakebites. The diagnostic performance of injury biomarkers in Bothrops envenomation was evaluated. AKI was diagnosed using the Kidney Disease Improving Global Outcomes (KDIGO) criteria. There was an association between endothelial injury and increased risk for AKI in bothropic envenoming. Angiopoietin- 1 (Ang-1) and Vascular cell adhesion protein-1 (VCAM-1) were useful biomarkers to predict mild AKI [AUC-ROC: Ang-1 0.82, VCAM-1 0.76] within the interval of 8-16 h post Bothrops snakebites. The use of endothelial biomarkers VCAM-1 e Ang-1 within 12-16 h post-bite may be useful in the early stage of mild AKI related to Bothrops envenoming and might have an effect on the early intervention for renal protection in less severe Bothrops-related AKI.

Serial serum creatinine, SDMA and urinary acute kidney injury biomarker measurements in dogs envenomated by the European adder (Vipera berus)

Background

Acute kidney injury (AKI) is associated with high morbidity and mortality in dogs, but diagnosis may be impaired due the insensitivity of routine renal function biomarkers to detect earlier or milder forms of injury. Snake envenomation is one of several causes of AKI in dogs and humans. Dogs are commonly envenomated by the European adder (Vipera berus) between April and October each year, but few studies exist examining serial serum creatinine (sCr) and symmetric dimethylarginine (SDMA) measurements and AKI biomarkers in these dogs. Novel urinary biomarkers could improve clinical outcome by allowing earlier diagnosis of and intervention in AKI. The aim of this study was to assess the presence of AKI in dogs envenomated by V. berus at 12, 24 and 36 h after bite, as well as 14 days later, using sCr, SDMA and a panel of urinary AKI biomarkers normalised to urine creatinine (uCr), compared to a group of healthy control dogs.

Results

Thirty-five envenomated dogs and 35 control dogs were included. Serum creatinine did not exceed the upper reference limit at any time point in any dog after envenomation. Serum SDMA did not exceed 0.89 μmol/L in any dog. Compared to controls, urinary albumin/uCr, neutrophil gelatinase-associated lipocalin/uCr and monocyte chemotactic protein-1/uCr were significantly elevated 12 h (P <  0.0001, P <  0.0001, P = 0.01), 24 h (P <  0.001, P <  0.001, P = 0.002) and 36 h (P <  0.001, P <  0.001, P = 0.0008) after bite. Osteopontin/uCr was higher 24 and 36 h after bite (P < 0.0001), kidney injury molecule-1/uCr, interleukin-8/uCr and γ- glutamyl transferase/uCr were significantly higher 36 h after bite (P = 0.003, P = 0.0005, P = 0.001). Urinary cystatin C/uCr was not significantly different to controls at any timepoint. Biomarker/uCr ratios were not significantly different 14 days after envenomation compared to controls.

Conclusion

Urinary biomarker/Cr ratios are indicative of mild transient, non-azotaemic AKI in dogs envenomated by V. berus.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-021-02851-8.

Systematic Review of Human Poisoning and Toxic Exposures in Myanmar

The International Health Regulations (2005) promote national capacity in core institutions so that countries can better detect, respond to and recover from public health emergencies. In accordance with the ‘all hazards’ approach to public health risk, this systematic review examines poisoning and toxic exposures in Myanmar. A systematic literature search was undertaken to find articles pertaining to poisoning in Myanmar published between 1998 and 2020. A number of poisoning risks are identified in this review, including snakebites, heavy metals, drugs of abuse, agrochemicals and traditional medicine. Patterns of poisoning presented in the literature diverge from poisoning priorities reported in other lower-middle income countries in the region. The experience of professionals working in a Yangon-based poison treatment unit also indicate that frequently observed poisoning as a result of pharmaceuticals, methanol, and petroleum products was absent from the literature. Other notable gaps in the available research include assessments of the public health burden of poisoning through self-harm, household exposures to chemicals, paediatric risk and women’s occupational risk of poisoning. There is a limited amount of research available on poisoning outcomes and routes of exposure in Myanmar. Further investigation and research are warranted to provide a more complete assessment of poisoning risk and incidence.

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.

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.

Clinical, hematobiochemical, and pathological findings and therapeutic management of viperine snake envenomation in zebu cattle

The present investigation was carried out to study the epidemiology, clinical signs, bleeding profile, kidney function, and pathology and to evaluate the therapeutic protocol for viperine snake envenomation in zebu cattle over a period of 14 years. A total of 98 cases of viperine bite were reported with the highest incidence during monsoon months in grazing male zebu cattle. Ascending swelling over the affected limb with lameness or asymmetrical swelling over the face with dyspnea was a consistent clinical finding. Increased bleeding tendency was invariably observed in ailing cattle with major bleeding from the site of the bite. Hematobiochemistry showed neutrophilic leukocytosis, thrombocytopenia, prolonged capillary blood clotting time, and elevation of BUN and creatinine. The characteristic gross pathological lesions observed were widespread petechial to ecchymotic hemorrhages in the lungs, liver, heart, spleen, abomasal mucosa, and intramuscular or subcutaneously at the site of bite. Histopathological examination revealed presence of necrohemorrhagic changes within the liver, heart, kidneys, skeletal muscles, and subcutaneously or intradermally at the site of bite. Diagnosis of viperine snakebite was made based on circumstantial evidence of bite, progressive swelling, and bleeding at the site of bite. The severity was assessed based on prolongation of capillary blood clotting time, thrombocytopenia, and kidney dysfunction. Therapeutic protocol comprising polyvalent anti-snake venom along with supportive therapy for 5-9 days showed encouraging results with 88.30% survival rate. In conclusion, the precise diagnosis of viperine snake envenomation in cattle can be made from history and typical clinical signs while severity and treatment can be monitored based on bleeding profile.

Diagnostic Challenges of Acute Kidney Injury in Asia

Early diagnosis of acute kidney injury (AKI) is an important step to improve AKI outcome. In Asia, several distinct conditions of this region such as environment (tropical climate), socioeconomic status (high-resource and low-resource settings), process of care (shortage of nephrologists), exposure factors (specific tropical infections such as leptospirosis, malaria, dengue), and inherent factor (aging) make the diagnosis of AKI in Asia more challenging than in other parts of the world. To improve the diagnosis of AKI, novel tools such as clinical risk scores, AKI alert systems, and telemedicine should be implemented into current clinical practice.

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.

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.

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.

Exploring circulatory shock and mortality in viper envenomation: a prospective observational study from India

BACKGROUND

Viper envenomation contributes to nearly 50% of snake-bite deaths in India, chiefly due to circulatory shock. The mechanisms leading to circulatory shock include bleeding, capillary leak syndrome (CLS) and myocardial depression. Pituitary-adrenal axis involvement in circulatory shock, though described, has not been fully elucidated.

AIM

To identify predictors of circulatory shock and mortality in viper envenomation and explore the role of pituitary-adrenal axis in circulatory shock.

DESIGN

Prospective hospital-based observational study.

METHODS

Once a syndromic diagnosis of viper envenomation was made, relevant clinical and laboratory data were collected. Serum cortisol was estimated in those with circulatory shock. Post-mortem examination of pituitary, kidneys and adrenals was performed. Adjusted odds-ratios were calculated for respective risk-factors for shock and mortality using multivariable logistic regression with backward elimination strategy.

RESULTS

Of 248 patients of viper envenomation treated at our hospital, circulatory shock was present in 19% and in-hospital mortality was 23%. CLS, circulatory shock, bleeding and requirement of > 20 vials of antivenom predicted mortality. Ischaemic and haemorrhagic necrosis of pituitary or adrenals was present in 51% of post-mortem specimens. Disseminated intravascular coagulation (DIC) and CLS were strong predictors of pituitary haemorrhage.

CONCLUSION

Predictors of mortality - bleeding, CLS and requirement of high antivenom doses are warning signs which can alert clinicians to patients who may have poor outcomes. Our study points to a definite role of pituitary-adrenal axis in circulatory shock supports the hypothesis that pituitary involvement in viper envenomation closely resembles Sheehan syndrome. The mechanism of pituitary involvement appears to be a result of increased susceptibility of the swollen gland secondary to CLS and micro thrombi deposition in DIC.

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.

Snakebite envenoming

Snakebite envenoming is a neglected tropical disease that kills >100,000 people and maims >400,000 people every year. Impoverished populations living in the rural tropics are particularly vulnerable; snakebite envenoming perpetuates the cycle of poverty. Snake venoms are complex mixtures of proteins that exert a wide range of toxic actions. The high variability in snake venom composition is responsible for the various clinical manifestations in envenomings, ranging from local tissue damage to potentially life-threatening systemic effects. Intravenous administration of antivenom is the only specific treatment to counteract envenoming. Analgesics, ventilator support, fluid therapy, haemodialysis and antibiotic therapy are also used. Novel therapeutic alternatives based on recombinant antibody technologies and new toxin inhibitors are being explored. Confronting snakebite envenoming at a global level demands the implementation of an integrated intervention strategy involving the WHO, the research community, antivenom manufacturers, regulatory agencies, national and regional health authorities, professional health organizations, international funding agencies, advocacy groups and civil society institutions.