Acute renal failure following poisonous snakebite

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

Use of Antibiotics following Snakebite in the Era of Antimicrobial Stewardship

Even though there are guidelines for the management of snakebite envenoming (SBE), the use of antibiotics in this pathology remains controversial. The aim of this study is to provide a narrative review of the literature and recommendations based on the best available evidence regarding antibiotic use in SBE. We performed a narrative review of relevant literature regarding SBE and antibiotic use as prophylaxis or treatment. A total of 26 articles were included. There is wide use of antibiotics in SBE; nevertheless, infection was not necessarily documented. The antibiotics used varied according to the study, from beta lactams to lincosamide and nitroimidazoles, and from monotherapy to combined antimicrobials. The most common recommendations were to manage skin and soft tissue infections and avoid infectious complications, but these suggestions are not necessarily based on bacteriological findings. Prophylactic use of antibiotics in SBE is discouraged in most studies. Antibiotic prescription in SBE should be based on the susceptibility of microorganisms isolated from the affected tissue or identified in snakes' oral cavities. Antibiotics should be reserved only for patients with a demonstrated infection, or those at a high risk of developing an infection, i.e., presenting severe local envenoming, local signs of infection, or those with incorrect manipulation of wounds. Prospective studies are needed to correlate microbiological findings at the wound site and the response to antibiotic use.

Erythrocyte haemotoxicity profiling of snake venom toxins after nanofractionation

Snakebite is classified as a priority Neglected Tropical Disease by the World Health Organization. Understanding the pathology of individual snake venom toxins is of great importance when developing more effective snakebite therapies. Snake venoms may induce a range of pathologies, including haemolytic activity. Although snake venom-induced erythrocyte lysis is not the primary cause of mortality, haemolytic activity can greatly debilitate victims and contributes to systemic haemotoxicity. Current assays designed for studying haemolytic activity are not suitable for rapid screening of large numbers of toxic compounds. Consequently, in this study, a high-throughput haemolytic assay was developed that allows profiling of erythrocyte lysis, and was validated using venom from a number of medically important snake species (Calloselasma rhodostoma, Daboia russelii, Naja mossambica, Naja nigricollis and Naja pallida). The assay was developed in a format enabling direct integration into nanofractionation analytics, which involves liquid chromatographic separation of venom followed by high-resolution fractionation and subsequent bioassaying (and optional proteomics analysis), and parallel mass spectrometric detection. Analysis of the five snake venoms via this nanofractionation approach involving haemolytic assaying provided venom-cytotoxicity profiles and enabled identification of the toxins responsible for haemolytic activity. Our results show that the elapid snake venoms (Naja spp.) contained both direct and indirect lytic toxins, while the viperid venoms (C. rhodostoma and D. russelii) only showed indirect lytic activities, which required the addition of phospholipids to exert cytotoxicity on erythrocytes. The haemolytic venom toxins identified were mainly phospholipase A2s and cytotoxic three finger toxins. Finally, the applicability of this new analytical method was demonstrated using a conventional snakebite antivenom treatment and a small-molecule drug candidate to assess neutralisation of venom cytotoxins.

Schistocyte quantitation, thrombotic microangiopathy and acute kidney injury in Australian snakebite coagulopathy [ASP28]

INTRODUCTION

The major systemic manifestation of hemotoxicity in human snakebite envenoming is venom-induced consumption coagulopathy (VICC). A subset of patients with VICC develop thrombotic microangiopathy (TMA), in which acute kidney injury (AKI) occurs. We aimed to investigate the association between schistocytosis in snakebite patients with VICC and AKI, compared to non-envenomed patients.

METHODS

Serial blood films collected from a prospective cohort of snakebite patients (Australian Snakebite Project) were examined. Cases were classified a priori as non-envenomed snakebites (normal controls), envenomed without VICC, partial VICC without AKI, complete VICC without AKI, and VICC with AKI based on defined clinical and laboratory criteria. The percentage of schistocytes between groups was compared and correlated by Kendall's tau b test.

RESULTS

Seven hundred and eighty blood films from 234 snakebite cases were analyzed. There was a statistically significant correlation (τ = .69, SE .03, P < .001) for schistocytosis between the ordered groups of non-envenomed snakebites, envenomed without VICC, partial VICC without AKI, complete VICC without AKI, and VICC with AKI groups. Patients with VICC and AKI had a platelet nadir median of 42 × 10⁹ /L (interquartile range [IQR] :25-130 × 10⁹ /L), hemoglobin nadir of median 107 g/L (IQR 66-122 g/L), and maximum LDH median of 1128 U/L (IQR 474-3255 U/L). A 1.0% threshold for schistocytosis yielded 90% sensitivity (95% CI: 67%-98%) and 71% specificity (95% CI: 62%-79%) for predicting AKI in patients with VICC.

CONCLUSION

Schistocyte quantitation has good diagnostic utility in snakebite patients with VICC. A definition of snakebite TMA as MAHA with ≥1.0% schistocytes and thrombocytopenia, would appear to be appropriate.

Snakebite associated thrombotic microangiopathy: a systematic review of clinical features, outcomes, and evidence for interventions including plasmapheresis

Snakebite is a neglected tropical disease with significant morbidity and mortality. Thrombotic microangiopathy (TMA) is an important but poorly understood complication of snakebite associated with acute kidney injury (AKI). Numerous treatments have been attempted based on limited evidence. We conducted a systematic review of TMA following snakebite using a pre-determined case definition of blood film red cell schistocytes or histologically diagnosed TMA. The search strategy included major electronic databases and grey literature. We present a descriptive synthesis for the outcomes of AKI, dialysis free survival (DFS), other end-organ damage, overall survival, and interventions with antivenom and therapeutic plasmapheresis (TPE). This study was prospectively registered with PROSPERO (CRD42019121436). Seventy-two studies reporting 351 cases were included, predominantly small observational studies. Heterogeneity for study selection, design, reporting and outcomes were observed. The commonest envenoming species were hump-nosed vipers (Hypnale spp.), Russell's viper (Daboia russelii) and Australian brown snakes (Pseudechis spp.). The prevalence of TMA was at least 5.4% in proven and probable Hypnale bites, and 10-15% of Australian elapid envenomings, AKI occurred in 94% (293/312) of TMA cases, excluding case reports. The majority of cases with AKI required dialysis. Included prospective and retrospective cohort studies reporting interventions and renal outcomes showed no evidence for benefit from antivenom or TPE with respect to DFS in dialysis dependant AKI. The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) assessment for quality of accumulated evidence for interventions was low. The major complication of TMA following snakebite is AKI. AKI improves in most cases. We found no evidence to support benefit from antivenom in snakebite associated TMA, but antivenom remains the standard of care for snake envenoming. There was no evidence for benefit of TPE in snakebite associated TMA, so TPE cannot be recommended. The quality of accumulated evidence was low, highlighting a need for high quality larger studies.

Bedside Coagulation Tests in Diagnosing Venom-Induced Consumption Coagulopathy in Snakebite

Venom-induced consumption coagulopathy is the most important systemic effect of snake envenoming. Coagulation tests are helpful to accurately and promptly diagnose venom-induced consumption coagulopathy and administer antivenom, which is the only specific treatment available. However, bedside clotting tests play a major role in diagnosing coagulopathy in low-income settings, where the majority of snakebites occur. We conducted a literature search in MEDLINE^® from 1946 to 30 November 2019, looking for research articles describing clinical studies on bedside coagulation tests in snakebite patients. Out of 442 articles identified, 147 articles describing bedside clotting assays were included in the review. Three main bedside clotting tests were identified, namely the Lee–White clotting test, 20-min whole blood clotting time and venous clotting time. Although the original Lee–White clotting test has never been validated for snake envenoming, a recently validated version has been used in some South American countries. The 20-min whole blood clotting time test is the most commonly used test in a wide range of settings and for taxonomically diverse snake species. Venous clotting time is almost exclusively used in Thailand. Many validation studies have methodological limitations, including small sample size, lack of case-authentication, the inclusion of a heterogeneous mix of snakebites and inappropriate uses of gold standard tests. The observation times for bedside clotting tests were arbitrary, without proper scientific justification. Future research needs to focus on improving the existing 20-min whole blood clotting test, and also on looking for alternative bedside coagulation tests which are cheap, reliable and quicker.

Fatal Rattlesnake Envenomation in Northernmost Brazilian Amazon: A Case Report and Literature Overview

Snakebite envenomations are classified as Category A Neglected Tropical Diseases by the World Health Organization. In Brazil, 405 snake species are distributed among 11 families, with the genera Bothrops and Crotalus being the most studied and main responsible for severe and lethal envenomations. In the country, Crotalus genus (i.e., rattlesnakes) is represented by Crotalus durissus species, showing seven different subspecies distributed along the country, including Crotalus durissus ruruima, which inhabits Roraima, the Brazilian nothermost state from Amazon forest. Here, we report a fatal case of a severe envenomation following a rattlesnake bite. The patient presented classic crotalic neurological signs and symptoms such as ptosis, drooling of saliva, sluggishness, macroscopic hematuria, and oliguria, which evolved to acute kidney failure (AKF) and hemodynamic instability. Although the patient was treated with the specific antivenom therapy, the severe envenomation resulted in three cardiac arrests and death of the victim in less than 38 h. This study discusses the causes of the patient death, the features of rattlesnake venom-induced AKF, and shows evidences that the Brazilian crotalic antivenom should be improved to treat rattlesnake envenomations caused by C. d. ruruima venom in Roraima state.

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.

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.

A Retrospective Study of Acute Renal Failure in Children: Its Incidence, Etiology, Complications and Prognosis

BACKGROUND

Acute renal failure (ARF) developed due to various causes and may lead to significant morbidity and mortality among pediatric patients.

OBJECTIVES

The study was conducted to determine the incidence, etiology, outcome of treatment and clinical presentation of ARF in pediatric patients in Somalia.

METHODS

Comprehensive case history of 39 pediatric patients below 12 years of age, admitted with renal diseases in four tertiary care hospitals in Hargeisa and Borama cities in Somalia during December 2015 to November 2016. They were subjected to clinical investigation and laboratory test analysis based on the inclusion criteria of renal insufficiency characterized by serum creatinine level more than 1.5 mg/dl.

RESULTS

ARF was most commonly found in five to 12 years age group (53.8%) compared to infant (zero to one year) and pre-school (one to five years) children (23.08%). Mean age of presentation was 6.14 years. Male female ratio in this study was 1.2: 1. Most common presenting clinical feature in our study was oliguria (97.43%), swelling (69.2%), fever (84.1%), abdomen pain and nausea-vomiting (41.02%). Common clinical signs were edema (66.66%), altered sensorium (51.28%), hematuria (48.71%) and hypertension (38.46%). Snake bite and acute post streptococcal glomerulonephritis were the two most common causes of ARF in children in our study. Common complications were hypertension (38.46%), anemia (35.89%), hyperkalemia (25.64%) and infection (20.51%), all of which were within the previously reported range. The factors which correlated positively with increased mortality and morbidity were females with age below one year , etiology like septicemia and systemic lupus erythematosus (SLE), high peak serum creatinine concentration and complicated by disseminated intravascular coagulation (DIC).

CONCLUSION

Many causes of ARF are preventable and it should be possible to reduce mortality and morbidity due to ARF through purposive preventive measure and availability of the better medical facility.

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

A Multidisciplinary Approach with Hyperbaric Oxygen Therapy Improve Outcome in Snake Bite Injuries

Aim:

Snakebite injuries are common in tropical India among those who are involved in outdoor activities. These injuries results in cellulitis, gangrene at the bite area, bleeding manifestations, compartment syndrome, regional lymphadenopathy, septicemia, hypotension, and disseminated intravascular coagulation (DIC) resulting in significant morbidity and mortality. The purpose of this study is to share our experience of multidisciplinary approach in the management of snakebite injuries of the extremities with various treatment modalities including hyperbaric oxygen (HBO) therapy, surgical debridement, and soft tissue reconstruction to provide an effective treatment for snake bite injuries.

Methods:

The study was conducted in the Department of Plastic Surgery, during the period October 2012–December 2014, wherein all the patients who were admitted with snakebite injuries were enrolled and the patients treated in plastic surgery department were included into the study. Out of total 766 patients, there were 323 patients treated with anti snake venom (ASV) and 29 died among the treated patients; 205 patients belonged to pediatric age group.

Results:

Out of 112 patients referred to Department of Plastic Surgery, 50 cases presented with cellulitis, 24 patients with compartment syndrome, and 38 patients were referred for the management of soft tissue cover over the extremities. Among 112 patients, 77 involved the lower extremity and 35 the upper extremity.

Conclusion:

Multidisciplinary approach including hyperbaric oxygen (HBO) therapy improves outcome in the management of snakebite injuries of the extremities.

Snakebite mediated acute kidney injury, prognostic predictors, oxidative and carbonyl stress: A prospective study

Snake bite is an occupational hazard in India and important preventable cause of acute kidney injury (AKI). This study was done to estimate the magnitude of snakebite-induced AKI (SAKI) who required renal replacement therapy, prognostic predictors, and final outcome, and to measure the oxidative and carbonyl stress (CS) level in SAKI patient who underwent hemodialysis (HD). All SAKI patients dialyzed between April 2010 and July 2011 in NRS Medical College were included. Demographical, clinical, and biochemical data were analyzed, and patients are followed to discharge or death. Oxidative and CS markers (advanced oxidation protein product [AOPP], advanced glycation end product, pentosidine, dityrosine, thioberbituric acid reactive substance, and methylglyoxal [MG]) were measured in 48 SAKI patient requiring HD. About 155 SAKI patients (M: F 2.2:1) received HD. Of them. The age was 36.2 (range 4–74) years. The most common site of the bite was lower limb (88.7%). Oliguria and bleeding manifestation were the common presentation. Hypotension was found in 52 (33.5%) cases, cellulitis and inflammation were found in about 63%. Mean creatinine was 4.56 ± 0.24 mg/dl. About 42 (27.1%) had disseminated intravascular coagulation (DIC). 36 (78.2%) had cellulites, 24 (52.2%) had hypotension or shock at initial presentation (P < 0.05), bleeding manifestation was found in 37 (80.4%), and 22 (47.8%) had DIC (P < 0.05). Forty-six (29.7%) patient died. DIC and hypotension/shock at initial presentation came out as an independent predictor of death. Among all markers measured for oxidative and CS (n = 48) AOPP and MG came out as an independent predictor (P < 0.05) of adverse outcome. Hypotension, DIC, AOPP, and MG were a poor prognostic marker in SAKI patients requiring dialysis.

Acute Kidney Injury and Rhabdomyolysis After Protobothrops flavoviridis Bite: A Retrospective Survey of 86 Patients in a Tertiary Care Center

Acute kidney injury (AKI) is the main cause of death for victims of hematoxic snakebites. A few studies have described improvement in AKI rates in snakebite cases, but the reasons for the improvement have not been investigated. Eighty-six patients with Protobothrops flavoviridis bites admitted to a single center from January 2003 through March 2014 were included in the study. Clinical variables, including age, sex, blood pressure (BP), and serum creatinine (S-Cre), on admission were compared between patients with and without AKI. One patient died of disseminated intravascular coagulation following AKI (mortality rate 1.1%). Six patients developed AKI with rhabdomyolysis. Systolic BP, S-Cre, serum creatine kinase, white blood cell count, and platelet count differed significantly between the AKI and non-AKI groups (P = 0.01). Three of the six patients were physically challenged to a degree that made it difficult for them to move or communicate, and these difficulties likely exacerbated the severity of snakebite complications. Our study demonstrated that the risk of snakebite-induced AKI for physically challenged patients was high. To further reduce mortality due to snakebite-induced AKI, we need to make it possible for physically challenged patients to receive first aid sooner.

Russells Viper Envenomation-associated Acute Kidney Injury in Children in Southern India

OBJECTIVE

To determine the frequency and risk factors of acute kidney injury in children with Russells viper envenomation using Acute Kidney Injury Network definition and classification system.

METHODS

A prospective observational study recruiting 61 subjects managed as per the National Snakebite Protocol.

RESULTS

45.9% of envenomed children had acute kidney injury. The median (IQR) of the maximum serum creatinine level during hospitalization was 2 (1.3-4.8) mg/dL. The distribution of stages 1, 2 and 3 of acute kidney injury was 32.1%, 17.9% and 50% respectively. Dialysis was required in 35.7% of the children with acute kidney injury.

CONCLUSION

Acute kidney injury is common with Russells viper envenomation. Native treatments and bleeding manifestations were associated with acute kidney injury in our patient population.

The report of sustained low-efficiency dialysis (SLED) treatment in fifteen patients of severe snakebite

To investigate the therapeutic efficacy of sustained low-efficiency dialysis (SLED) in severe snakebite patients. Fifteen patients of severe snakebite was treated with SLED from July 2005 to August 2009 were included in the study. Central venous access was established in all patients. SLED was administered using Dialog(+) dialyzer (B. Braun, Germany). SLED sessions were 6-12 h in duration at a blood flow rate of 200 ml/min and a dialysate flow rate of 300 ml/min. Heparin or low molecular weight heparin was used as anticoagulant. Biochemical indicators, APACHE II scores before and after SLED, and clinical outcomes were evaluated. The levels of serum creatinine, glutamic-oxaloacetic transaminase, glutamic-pyruvic transaminase, creatine kinase isozyme MB, and creatine kinase were significantly lower than the level before SLED (P < 0.05); the level of cholinesterase was significantly higher after SLED (P < 0.01); the APACHE II score before SLED was 14.1 ± 3.8, but decreased significantly to 7.9 ± 1.4, 6.2 ± 1.1, and 4.2 ± 0.8 on days 1, 2, and 7 after SLED, respectively (P < 0.01). Three patients died on days 1, 3, and 4 after SLED, respectively. The remaining twelve patients were either cured or showed improvement at the time of discharge. The survival rate was 80 % where as mortality was 20 %. SLED may be an effective treatment option in severe snakebite patients. It can reduce mortality, thereby, resulting in increased survival rates.

A study on the acute kidney injury in snake bite victims in a tertiary care centre

INTRODUCTION

Snake bite is a common medical emergency and an occupational hazard, more so in tropical India, where farming is a major source of employment. Viper bites are more common than other poisonous snakebites in humans. The World Health Organization has estimated that there are approximately 1,25,000 deaths among 2,50,000 poisonous snake bites worldwide every year, of which India accounts for 10,000 deaths. Acute kidney Injury (AKI) is an important consequence of a snake bite and its proper supportive management after the anti-venom administration is of utmost importance, for a good patient outcome.

AIMS AND OBJECTIVES

1. To assess the risk factors and the prognostic factors in snake-bite induced Acute Kidney Injury.2. To determine the outcome of snake bite patients with AKI in a tertiary care centre in Karnataka, India.

METHODOLOGY

This prospective study was carried out at Vijaynagar Institute of Medical Sciences, Bellary, Karnataka, India. This institute is a referral government hospital in north Karnataka, India.

STUDY DESIGN

This was a prospective and descriptive type of study.

RESULTS

A total of 246 cases of venomous snakebite were included in this study, who were admitted in the hospital from November 2007 to October 2008. Among the AKI and the non-AKI patients, Illiteracy was more among the patients who suffered from AKI (75%). In our study, among all the patients (both AKI and non-AKI patients), viper bite was the commonest and it was seen in 31(91.6%) cases among the AKI patients and in 142 (67.6%) cases among the non-AKI patients. In our study, a majority of the patients who developed AKI had initially visited traditional healers before visiting our hospital, which was found to be statistically significant. In the present study, disseminated intravascular coagulation (DIC) and intravascular haemolysis were found to be predominant among the AKI patients. The "Bite to Needle" time was significantly more in the patients who developed AKI as compared to that in those who developed non-AKI. Out of 36 patients who suffered from AKI, 28 (77.7%) patients survived. Among them, 27(96.7%) patients developed cellulitis, 25(89.5%) had regional lymphadenopathy, 22(81.2%) were bitten at their lower limbs, and 6 (23.8%) patients developed bleeding manifestations.

CONCLUSION

This study concludes that acute kidney injury occurs in 14.6% of the victims of snake bite. The common manifestations include cellulitis, bleeding manifestations and gangrene at the site of the bite.

Community-acquired acute kidney injury in tropical countries

Community-acquired acute kidney injury (AKI) in developing tropical countries is markedly different from AKI in developed countries with a temperate climate, which exemplifies the influence that environment can have on the epidemiology of human diseases. The aetiology and presentation of AKI reflect the ethnicity, socioeconomic factors, climatic and ecological characteristics in tropical countries. Tropical zones are characterized by high year-round temperatures and the absence of frost, which supports the propagation of infections that can cause AKI, including malaria, leptospirosis, HIV and diarrhoeal diseases. Other major causes of AKI in tropical countries are envenomation; ingestion of toxic herbs or chemicals; poisoning; and obstetric complications. These factors are associated with low levels of income, poor access to treatment, and social or cultural practices (such as the use of traditional herbal medicines and treatments) that contribute to poor outcomes of patients with AKI. Most causes of AKI in developing tropical countries are preventable, but strategies to improve the outcomes and reduce the burden of tropical AKI require both improvements in basic public health, achieved through effective interventions, and increased access to effective medical care (especially for patients with established AKI).

Long-term renal outcome of snake bite and acute kidney injury: a single-center experience

BACKGROUND

Snake bite can cause acute kidney injury (AKI) through multiple mechanisms. Many of these patients have severe kidney injury requiring renal replacement therapy. The long-term outcome of survivors of such severe AKI is not known.

METHODS

We prospectively followed up 60 patients who developed dialysis-requiring severe AKI following snake bite and had survived the hospital stay.

RESULTS

A total of 25 (41%) patients showed persistent renal involvement in the form of renal dysfunction, proteinuria, or hypertension at a mean period of follow-up of 45 months. Totally 5% of the patients progressed to end-stage renal disease (ESRD) while 20% had glomerular filtration rate (GFR) <45 mL/min.

CONCLUSIONS

Long-term outcome of snake bite and AKI is not benign with a significant percentage of patients continuing to have features of persistent renal damage.

Effect of purified Russell's viper venom-factor X activator (RVV-X) on renal hemodynamics, renal functions, and coagulopathy in rats

Acute renal failure (ARF) is the most frequent and a serious complication in victims of Russell's viper snakebites. Russell's viper venom-factor X activator (RVV-X) has been identified as a main procoagulant enzyme involving coagulopathy, which might be responsible for changes in renal hemodynamics and renal functions. Here, we purified RVV-X from crude Russell's viper venom to study renal hemodynamics, renal functions, intravascular clot, and histopathological changes in Sprague-Dawley rats. Changes in renal hemodynamics and renal functions were evaluated by measuring the mean arterial pressure, glomerular filtration rate (GFR), effective renal plasma flow (ERPF), effective renal blood flow (ERBF), renal vascular resistance (RVR), and fractional excretion of electrolytes. After 10 min, rats receiving both crude venom and purified RVV-X decreased GFR, ERPF, and ERBF and increased RVR. These changes correlated to renal lesions. Along with the determination of intravascular clot, rats injected with purified RVV-X increased the average D-dimer level and reached a peak at 10 min, declined temporarily, and then reached another peak at 30 min. The temporal association between clots and renal dysfunction was observed in rats within 10 min after the injection of purified RVV-X. These findings suggested RVV-X as a major cause of renal failure through intravascular clotting in the renal microcirculation.

Forensic diagnosis and classification of snakebite (neurotoxic and haemotoxic) from renal changes at autopsy: morphological and histological determinants using a semi-quantitative method

Mortality due to poisonous snakebite is an emerging public health concern. Of late, snakebite has drawn global attention. Snakebite is a well-known cause of renal pathology especially in the haemotoxic group. Deaths due to renal failure are very common in envenomation due to poisonous snakebite. In this investigation our aim was to devise autopsy-proven diagnostic criteria of snakebite from the renal changes to confirm and classify the type of snakebite in forensic casework. That would be of practical help to the forensic pathologist with access to limited resources. An arbitrary scoring system from histology was adopted for the present semi-quantitative analysis. The scoring system (with scores from 0 to 5) developed by the present study was effective, valid and was able to distinguish between snakebite and control. The score obtained at histology in cases of snakebite was significantly different from the control group (Mann-Whitney U = 71.5; P = 0.011). Using stepwise linear discriminant function (DF) analysis, the score (Mukhopadhyay's score [MS]) was seen to be the only predictor of the type of snakebite. This model (DF = 1.05 x MS-1.78) could correctly classify 93.3% of the cases into neurotoxic and haemotoxic variety of offending snake. This is an effective, cheap and easy semi-quantitative method of distinguishing neurotoxic and haematoxic snakes from the renal changes at autopsy. It would be useful for practical application in centres where sophisticated biochemical or immunological analyses are not available due to limited resources.

Community-acquired acute kidney injury in Asia

Asia, the largest continent in the world, is heterogeneous in the ethnic, socioeconomic, and developmental status of its populations. A vast majority of it is poor with no adequate access to modern health care, making an accurate estimation of the nature and extent of acute kidney injury (AKI) difficult. Community-acquired AKI in otherwise healthy individuals is common, and the population developing AKI is younger compared with its counterparts in Europe or North America. The etiologic spectrum varies in different geographic regions of Asia depending on environmental, cultural, and socioeconomic factors. Some of the etiologic factors include AKI in relation to infectious diseases, intravascular hemolysis caused by glucose 6-phosphate dehydrogenase deficiency, poisonings caused by industrial chemicals or copper sulphate, animal venoms, natural medicines, heat stroke, and after complications of pregnancy. Preventive opportunities are missed because of failure to recognize the risk factors and early signs of AKI. Patients often present late for treatment, leading to multi-organ involvement and increased mortality. The exact etiologic diagnosis cannot be established in many instances because of a lack of appropriate laboratory support. Modern methods of renal replacement therapy are not universally available; and intermittent peritoneal dialysis is still widely practiced in many areas.

Snakebite-induced acute kidney injury: data from Southeast Anatolia

Renal failure is an important complication of snakebite and a major cause of mortality. We aimed to study the clinical profile of snake envenomation in Southeast Anatolia, Turkey, in an adult population. We retrospectively analyzed the records of 200 snakebite victims from 1998 to 2006 at the Dicle University School of Medicine, Diyarbakir, Turkey. Sixteen patients (8%) developed AKI (acute kidney injury). Of those, 25% required dialysis and 18% died. There was no difference between groups in age, arrival time to hospital, and hospital stay time. Both groups received similar hydration and therapy at admission. Disseminated intravascular coagulation (DIC) was observed in 25% of the AKI group and was significantly higher than the non-AKI group (7.1%; p = 0.014). There was no significant difference regarding hemoglobin, platelet levels, and prothrombin time at admission. The prevalence of thrombocytopenia (<150,000 K/UL ) was 60% in the AKI group and 40% in the non-AKI group (p > 0.05). WBC count was significantly higher in the AKI group than in those without AKI (p = 0.001); serum albumin was significantly lower in the AKI group than in those without AKI (p = 0.013). AKI is an important complication of snakebite that may lead to mortality. Despite some troublesome aspects due to its retrospective design, this is a large series from Southeast Anatolia of Turkey in an adult population. Subjects with high WBC, low albumin, and DIC should be closely followed up for the development of AKI.

Thrombotic microangiopathy from Australian brown snake (Pseudonaja) envenoming

BACKGROUND

Australian brown snake (genus Pseudonaja) envenoming causes a venom-induced consumptive coagulopathy (VICC). A proportion of cases go on to develop thrombotic microangiopathy characterized by thrombocytopenia, microangiopathic haemolytic anaemia (MAHA) and acute renal failure (ARF).

AIM

The aim of the study was to define better the natural history and empirical treatments for thrombotic microangiopathy in brown snake envenoming.

METHODS

A review of brown snake bites recruited to the Australian Snakebite Project (ASP), a national multicentre study of snake envenoming was undertaken. Serial data are recorded on clinical effects and laboratory results, including measurement of venom concentrations. We describe cases of thrombotic microangiopathy and compare these to cases without thrombotic microangiopathy.

RESULTS

From 32 cases of brown snake envenoming with severe VICC, four (13%) developed thrombotic microangiopathy, we also included two cases of thrombotic microangiopathy from prior to ASP. All six developed severe thrombocytopenia (<20 x 10(-9)/L), worst 3 days after the bite and resolving over a week, MAHA with fragmented red blood cells on the blood film and five developed anuric ARF requiring dialysis and lasting 2-8 weeks. All six received antivenom, which was delayed compared with other brown snake-envenoming cases. Four were treated with plasmapheresis. The severity and recovery of the thrombocytopenia, anaemia and renal function were similar with and without plasmapheresis. The median length of stay for MAHA cases was 14 days (interquartile range (IQR) 12-14) compared to 1.8 days (IQR 1.3-2) for all other cases.

CONCLUSION

Thrombotic microangiopathy resulting from brown snake bite appears to have a good prognosis and management should focus on early antivenom therapy and supportive care including dialysis. The role of plasmapheresis is yet to be defined.

Clinical characteristics of children with snakebite poisoning and management of complications in the pediatric intensive care unit

BACKGROUND

Venomous snakebite is an emergency condition with high morbidity and mortality in childhood. Nearly all venomous snakes in Turkey are members of the Viperidae family and show poisonous local and hematotoxic effects.

METHODS

A total of 77 children (mean age 9.9 +/- 2.9 years; age range 3-14 years) with venomous snakebites were investigated. General characteristics of the children, species of the snakes, localization of the bite, clinical and laboratory findings, treatment approaches, complications and prognosis were evaluated.

RESULTS

The male to female ratio was 1.4. Ninety-one per cent of cases were from rural areas. Most of the bites were seen in May and June. Mean duration between snakebites and admissions to our department was 13 +/- 6.5 h. According to a clinical grading score, 57.1% of patients presented to us as grade II. Mean leukocyte count, aspartate aminotransferase, lactate dehydrogenase, creatinine phosphokinase and protrombin time levels were above the normal ranges and mean activated partial tromboplastin time was below the normal range. Platelet counts inversely correlated with the grading score and duration of hospitalization. The most common complication that occurred during the treatment was tissue necrosis (13%). The mean hospital stay time was 6.3 +/- 6 days. Three children with disseminated intravascular coagulation died. Fasciotomies were performed to seven (9.1%) children due to compartment syndrome. Of 10 children with tissue necrosis, three (3.9%) had finger amputation and seven (9.1%) had toe amputation. Higher grading score on admission, platelet count below 120 000/mm3, AST over 50 IU/L and existence of evident ecchymosis were found as significant risk factors for development of serious complications by logistic regression analysis.

CONCLUSIONS

Snakebite poisoning is an emergency medical condition that is particularly important in childhood. The envenomations are still considerable public health problems with a high morbidity and mortality in rural areas of Turkey.

Snakebite-induced acute renal failure. A case report and review of the literature

Snakebite is not an uncommon cause of acute renal failure (ARF) in developing countries. We report a12-year-old boy who presented with oliguric ARF following snakebite. He had pallor, icterus, generalized edema, hypertension, and was oliguric. Investigations revealed severe azotemia, microangiopathic hemolytic anemia, thrombocytopenia, prolonged coagulation parameters, and raised fibrin degradation products, suggesting disseminated intravascular coagulation as the cause of ARF. The patient improved with antisnake venom, dialysis, and other supportive treatment.

Vipera palaestinae envenomation in 327 dogs: a retrospective cohort study and analysis of risk factors for mortality

Vipera palaestinae (Vp), formerly a subspecies of the near east viper Vipera xanthina, is the most common poisonous snake in Israel and neighbouring countries (Jordan, Lebanon and Syria), and is responsible for most envenomations in humans and domestic animals. Hospital records were retrospectively reviewed for confirmed cases of Vp envenomations in dogs over a 13-year period and 327 cases were included in the study. Most envenomations occurred between May and October, and between 02:00 and 10:00 PM. The most frequent clinical signs included: local swelling and oedema (99.6%), viper teeth penetration marks (51%), tachypnoea (50%), panting (44%), increased body temperature (19.2%), tachycardia (>160/min, 19%), salivation (18%) and lameness (15.6%). Common haematological findings included: increased haematocrit (47%), increased haemoglobin concentration (45%), leucocytosis (39%), and thrombocytopenia (30%). The prothrombin time and activated partial thromboplastin time were prolonged in 68 and 21% of the dogs, respectively. Blood biochemistry abnormalities included increased activities of muscle enzymes, hyperglycaemia, hyperbilirubinaemia, hyperglobulinaemia and hypocholesterolaemia. The mortality rate was 4% (13 dogs). The following variables were significantly (p < 0.05) associated with mortality: body weight below 15 kg (p = 0.01), limb envenomation (0.008), envenomation at night (p = 0.025), severe lethargy (P < 0.001), hypothermia (p = 0.04), systemic bleeding (p = 0.001), shock (p = 0.007), dyspnoea (p = 0.002), tachycardia (p = 0.002), thrombocytopenia (p = 0.02), and glucocorticosteroid therapy (p = 0.002). Dogs younger than 4 years had a lower death risk (p = 0.01). The association of steroid therapy with increased mortality suggests that the use of steroids in Vp envenomations may be harmful. Specific antivenom therapy (10 ml/dog) was not associated with a higher survival rate, thus its use, dose and timing of administration should be further investigated.

Snakebite induced acute interstitial nephritis: report of a rare entity

Snakebite induced acute renal failure continues to occur in many tropical areas of the world. Renal histological lesions other than acute tubular necrosis and acute cortical necrosis as the cause of acute renal failure are rare. Only 3 cases of acute interstitial nephritis in patients with snakebite induced acute renal failure have been previously reported. We report a patient with acute renal failure following viperine snakebite due to acute interstitial nephritis. After a prolonged oliguric phase, there was complete recovery of renal function without institution of steroids. Interstitial nephritis may result from a hypersensitivity reaction to some component of the snake venom.

Ophidian envenomation strategies and the role of purines

Snake envenomation employs three well integrated strategies: prey immobilization via hypotension, prey immobilization via paralysis, and prey digestion. Purines (adenosine, guanosine and inosine) evidently play a central role in the envenomation strategies of most advanced snakes. Purines constitute the perfect multifunctional toxins, participating simultaneously in all three envenomation strategies. Because they are endogenous regulatory compounds in all vertebrates, it is impossible for any prey organism to develop resistance to them. Purine generation from endogenous precursors in the prey explains the presence of many hitherto unexplained enzyme activities in snake venoms: 5'-nucleotidase, endonucleases (including ribonuclease), phosphodiesterase, ATPase, ADPase, phosphomonoesterase, and NADase. Phospholipases A(2), cytotoxins, myotoxins, and heparinase also participate in purine liberation, in addition to their better known functions. Adenosine contributes to prey immobilization by activation of neuronal adenosine A(1) receptors, suppressing acetylcholine release from motor neurons and excitatory neurotransmitters from central sites. It also exacerbates venom-induced hypotension by activating A(2) receptors in the vasculature. Adenosine and inosine both activate mast cell A(3) receptors, liberating vasoactive substances and increasing vascular permeability. Guanosine probably contributes to hypotension, by augmenting vascular endothelial cGMP levels via an unknown mechanism. Novel functions are suggested for toxins that act upon blood coagulation factors, including nitric oxide production, using the prey's carboxypeptidases. Leucine aminopeptidase may link venom hemorrhagic metalloproteases and endogenous chymotrypsin-like proteases with venom L-amino acid oxidase (LAO), accelerating the latter. The primary function of LAO is probably to promote prey hypotension by activating soluble guanylate cyclase in the presence of superoxide dismutase. LAO's apoptotic activity, too slow to be relevant to prey capture, is undoubtedly secondary and probably serves principally a digestive function. It is concluded that the principal function of L-type Ca(2+) channel antagonists and muscarinic toxins, in Dendroaspis venoms, and acetylcholinesterase in other elapid venoms, is to promote hypotension. Venom dipeptidyl peptidase IV-like enzymes probably also contribute to hypotension by destroying vasoconstrictive peptides such as Peptide YY, neuropeptide Y and substance P. Purines apparently bind to other toxins which then serve as molecular chaperones to deposit the bound purines at specific subsets of purine receptors. The assignment of pharmacological activities such as transient neurotransmitter suppression, histamine release and antinociception, to a variety of proteinaceous toxins, is probably erroneous. Such effects are probably due instead to purines bound to these toxins, and/or to free venom purines.

Acute renal cortical necrosis--a study of 113 patients

Over a 28-year period, 113 out of 2986 (3.8%) patients dialysed for acute renal failure at a referral center in North India were diagnosed to have acute renal cortical necrosis (ACN). Obstetric causes were responsible for ACN in 56.6% patients and nonobstetric causes in 43.4%. Within the obstetric group, ACN developed in association with complications of late pregnancy in 37.1% and following septic abortion in 19.5%. The various nonobstetric causes included viperine snake bite in 14.2%, hemolytic uremic syndrome in 11.5%, renal allograft rejection in 5.3%, acute gastroenteritis in 4.4%, acute pancreatitis in 3.5%, septicemia in 2.7%, and trauma and drug-induced IV hemolysis in 0.9% patients. Total anuria was the commonest presenting feature and was noted in 78.8% of patients. Renal histology showed diffuse cortical necrosis in 62.8% and patchy lesions in 37.2% patients. Computerized tomography (CT scan) of the kidneys revealed characteristic diagnostic findings in all the 5 patients in whom it was done. Dialytic support could be withdrawn as a result of improvement in renal function in 19 patients with patchy cortical necrosis. Dialysis-free survival of as long as 12 years has been recorded. The present study shows that, in contrast to the Western world, ACN continues to be a common cause of acute renal failure in developing countries. CT scan of the kidneys is helpful in establishing an early diagnosis.

Proliferative glomerulonephritis in mice induced by sea snake (Aipysurus laevis) venom

Aipysurus laevis venom has been shown to have a direct nephrotoxic effect in mice. A single subcutaneous injection (0.075 mg/kg body wt.) of the whole venom caused acute renal tubular degeneration and proliferative glomerulonephritis. The tubular changes appeared within 1 hour and remained for at least 14 days. Mesangial proliferative glomerulonephritis developed within 3-10 days, and is characterised by mild mesangial proliferation, mesangial and glomerular basement membrane deposits. This is followed by a partial resolution and subsequent mesangial sclerosis. The exact pathogenesis of venom-induced glomerulonephritis is not clear although it may have an immunological basis similar to that seen in human poststreptococcal glomerulonephritis. It was not possible to clarify the nature of the deposits by conventional immunohistochemical stains.

The nephrotoxic action of Russell's viper (Vipera russelli) venom

Sixteen rabbits were injected s.c. with 2 LD50 doses of Russell's viper venom. Kidneys from 10 rabbits that died after envenomation were examined by microdissection and light microscopy. Nephrons from five animals showed destruction of the proximal tubules with normal distal tubules. Nephrons from three animals were normal throughout, while those from two animals were destroyed. In the in vitro experiment, kidney slices from normal rabbits were incubated with varying dilutions of Russell's viper venom, Russell's viper venom and antivenom mixture, antivenom alone or saline controls, at 37 degrees C for varying time intervals. Scattered areas of tubular damage were found in kidney tissues incubated in 5 mg/ml Russell's viper venom for 2 hr. This damage was prevented by antivenom. Abnormal appearances were not seen in kidney tissues incubated with antivenom alone or saline. In the present study, direct nephrotoxic action of Russell's viper venom was observed both in the in vivo and in vitro tests, however, part of the damage in vivo could be of an ischemic nature.

Snake-bite-induced acute renal failure in India

Acute renal failure complicates the course in 5% to 30% of victims of severe viper poisoning. No consensus exists on the single mechanism causing acute renal failure after viper bite. It is known, however, that viper venom induces several clinical abnormalities that favor the development of acute renal failure. These alterations include a varying degree of bleeding, hypotension, circulatory collapse, intravascular hemolysis, and disseminated intravascular coagulation with or without microangiopathy. A direct cytotoxic action of snake venom on the kidney is suspected, but convincing evidence is still lacking. Severe hypocomplementemia is consistently present, but I doubt its role in the causation of renal lesions. Hypersensitivity to venomous or antivenomous protein occasionally causes acute renal failure. In sea snake poisoning, myonecrosis and myoglobinuria appear to play the predominant pathogenetic role. The renal lesions of clinical significance in envenomed patients are acute tubular and patchy or diffuse cortical necrosis. Glomerulonephritis, interstitial nephritis, and papillary necrosis have been reported in rare patients. I trust that this overview of the clinical and basic-science aspects of snake-bite-induced acute renal failure will prompt investigators to further define the pathogenetic mechanisms involved. Lessons learned may aid patients with acute renal failure of diverse causes, both here in India and around the world.

Contribution of focal haemorrhage and microvascular fibrin deposition to fatal envenoming by Russell's viper (Vipera russelli siamensis) in Burma

In Burma, clinicopathological studies were carried out in three young farmers who died 15, 52 and 36 h after being bitten by Russell's vipers. Clinical features included local swelling, spontaneous systemic bleeding, defibrination, shock, cardiac arrhythmia, hypoglycaemia, coma and oliguria. On admission to hospital, 15, 48 and 21 h after the bites, serum venom antigen concentrations ranged from 50 to 130 ng/ml. Autopsies revealed widespread congestion and bleeding in the lungs, gastrointestinal and renal tracts, adrenals, heart, brain and anterior pituitary. There was histopathological evidence of focal haemorrhage and fibrin deposition at the site of the bite and in the pituitary, lungs and kidneys and acute tubular necrosis. Deposition of fibrin microthrombi results from the action of venom procoagulants. Shock was attributed to increased capillary permeability, revealed clinically by conjunctival oedema. Acute pituitary/adrenal failure in one case was explained by fibrin deposition and haemorrhage in the anterior pituitary--resembling Sheehan's syndrome. Acute tubular necrosis resulted from ischaemia caused by fibrin deposition and to prerenal factors. An intractable cardiac tachyarrhythmia may have been caused by subendocardial and myocardial haemorrhages.