Snakebite nephropathy (Review Article)

+Ophitoxaemia and myocardial infarction--the issues during primary angioplasty: a review

'The Big four' are the most poisonous snakes in India, and especially in Kerala. These include the cobra, the viper, the krait and the sea snake. Most of the poisonous snakebites in India occur in Kerala. We believe there are only a few reports of myocardial infarction after snakebites and most of these are viper bites. We believe this is the second case of primary angioplasty for a snakebite. There are at least a few potential issues in performing a primary angioplasty in a snakebite case, namely (1) Is it a thrombus or a spasm? (2) Are the bleeding parameters deranged? Will the patient tolerate tirofiban and other glycoprotein (GB) 2b3a inhibitors? Will he develop dangerous bleeding due to the high dose of heparin needed? Further, would we save the patient from myocardial infarction only to lose him to renal failure, both due to the nephrotoxicity of the venom, the kidney being further damaged by the contrast media used for the angioplasty? We discuss all these issues as they crossed our mind, and hope it will help further treatment in others. We would like to review the available literature on these points and describe a recent case of ours.

Viper bites complicate chronic agrochemical nephropathy in rural Sri Lanka

Snakebite is a common occupational health hazard among Sri Lankan agricultural workers, particularly in the North Central Province. Viperine snakes, mainly Russell's viper envenomation, frequently lead to acute renal failure. During the last two decades, an agrochemical nephropathy, a chronic tubulointerstitial disease has rapidly spread over this area leading to high morbidity and mortality. Most of the epidemiological characteristics of these two conditions overlap, increasing the chances of co-occurrence. Herein, we describe four representative cases of viperine snakebites leading to variable clinical presentations, in patients with chronic agrochemical nephropathy, including two patients presented with acute and delayed anuria. These cases suggest the possibility of unusual manifestations of snakebite in patients with Sri Lankan agrochemical nephropathy, of which the clinicians should be aware. It could be postulated that the existing scenario in the Central America could also lead to similar clinical presentations.

Mechanisms of acute kidney injury induced by experimental Lonomia obliqua envenomation

Lonomia obliqua caterpillar envenomation causes acute kidney injury (AKI), which can be responsible for its deadly actions. This study evaluates the possible mechanisms involved in the pathogenesis of renal dysfunction. To characterize L. obliqua venom effects, we subcutaneously injected rats and examined renal functional, morphological and biochemical parameters at several time points. We also performed discovery-based proteomic analysis to measure protein expression to identify molecular pathways of renal disease. L. obliqua envenomation causes acute tubular necrosis, which is associated with renal inflammation; formation of hematic casts, resulting from intravascular hemolysis; increase in vascular permeability and fibrosis. The dilation of Bowman's space and glomerular tuft is related to fluid leakage and intra-glomerular fibrin deposition, respectively, since tissue factor procoagulant activity increases in the kidney. Systemic hypotension also contributes to these alterations and to the sudden loss of basic renal functions, including filtration and excretion capacities, urinary concentration and maintenance of fluid homeostasis. In addition, envenomed kidneys increase the expression of proteins involved in cell stress, inflammation, tissue injury, heme-induced oxidative stress, coagulation and complement system activation. Finally, the localization of the venom in renal tissue agrees with morphological and functional alterations, suggesting also a direct nephrotoxic activity. In conclusion, the mechanisms of L. obliqua-induced AKI are complex involving mainly glomerular and tubular functional impairment and vascular alterations. These results are important to understand the mechanisms of renal injury and may suggest more efficient ways to prevent or attenuate the pathology of Lonomia's envenomation.

Bilateral renal cortical necrosis with end-stage renal failure following envenoming by Proatheris superciliaris: a case report

Acute bilateral renal cortical necrosis (BRCN) has been reported following envenoming by exotic venomous snakes. Proatheris superciliaris is a rare viper with restricted distribution in east Africa. Very little information is available on envenoming by this species. We herein describe the case of a 60-year-old professional wildlife photographer who was bitten on his thumb while photographing an adult specimen of P. superciliaris that he held at home in France. On admission, physical examination revealed severe hypertension and bruising with edema at the bite site. Within the following 24 h, he developed vomiting, diarrhea, acute lumbar pain and anuria. Laboratory tests showed acute kidney injury (serum creatinine 4.6 mg/dL), with thrombocytopenia, anemia and severe coagulopathy. Contrast-enhanced computed tomography scan revealed hypodense areas in the cortex of both kidneys consistent with diffuse BRCN. As no appropriate antivenom existed, only symptomatic care was given to the patient. Coagulation tests returned to normal within 48 h. The patient was placed on chronic hemodialysis, until he underwent successful kidney transplantation 18 months later. In developed countries, severe complications provoked by snake bites tend to be more frequent with the number of trendy exotic pets. Acute kidney injury, including BRCN, is a classic complication of viper bites. The present case of end-stage renal failure related to diffuse BRCN illustrates the potentially devastating effects of envenoming by P. superciliaris. Clinicians in developed countries should be informed about renal disorders and other potentially fatal complications of venomous snake bites and seek urgent expert advice for optimizing clinical management. Education and coaching of envenomed patients and exotic snake owners is mandatory to prevent dramatic accidents.

Hypopituitarism in patients with vasculotoxic snake bite envenomation related acute kidney injury: a prospective study on the prevalence and outcomes of this complication

Acute kidney injury (AKI) is common in patients with vasculotoxic snake bite (SB) envenomation but hypopituitarism (HP) is an uncommonly reported complication. We conducted a prospective observational study on survivors of SB-AKI who were evaluated and followed up from September 2010 till September 2012. Pituitary function tests were done if they developed any symptoms of HP. MRI of the hypothalamo-pituitary axis was done in those with documented HP. Response to therapy in the form of improvement in the quality of life (QoL) was evaluated by asking patients to mark on a visual analogue scale marked over 0-100 mm which was reported as percentage improvement. 126 patients were included for this study (30 were lost to follow up and were excluded). 25 cases were clinically suspected to have pituitary dysfunction and underwent evaluation with 9 (9.37%, n = 96) found to have evidence of HP. One child had partial empty sella on MRI with anterior as well as posterior pituitary abnormality and stunting; imaging was normal in others. Higher number of patients with HP had hypotension (p = 0.005, n = 7), coagulation abnormalities (p = 0.005, n = 9), severe clinical snake bite envenomation (p = 0.024, n = 9) and progression to chronic kidney disease (CKD) (p = 0.001, n = 5) as compared to those who did not. Dialysis dependence at presentation was not significantly different (p = 0.348, n = 9). Only development of CKD on follow up predicted the development of HP. Patients had an improvement in the QoL after treatment with mean score on the visual analogue scale of 66.67 ± 14.14%. HP is not very uncommon in patients with severe vasculotoxic SB-AKI. Threshold of clinical suspicion and evaluation should be low as it causes significant morbidity.

Acute kidney injury caused by Crotalus and Bothrops snake venom: a review of epidemiology, clinical manifestations and treatment

SUMMARY

Ophidic accidents are an important public health problem due to their incidence, morbidity and mortality. An increasing number of cases have been registered in Brazil in the last few years. Several studies point to the importance of knowing the clinical complications and adequate approach in these accidents. However, knowledge about the risk factors is not enough and there are an increasing number of deaths due to these accidents in Brazil. In this context, acute kidney injury (AKI) appears as one of the main causes of death and consequences for these victims, which are mainly young males working in rural areas. Snakes of the Bothrops and Crotalus genera are the main responsible for renal involvement in ophidic accidents in South America. The present study is a literature review of AKI caused by Bothrops and Crotalus snake venom regarding diverse characteristics, emphasizing the most appropriate therapeutic approach for these cases. Recent studies have been carried out searching for complementary therapies for the treatment of ophidic accidents, including the use of lipoic acid, simvastatin and allopurinol. Some plants, such as Apocynaceae, Lamiaceae and Rubiaceae seem to have a beneficial role in the treatment of this type of envenomation. Future studies will certainly find new therapeutic measures for ophidic accidents.

The Kidney and the Tropics

In this age of rapid globalization and travel, diseases that were previously prevalent in warmer countries within the tropics are increasingly found in other countries with more temperate climates. A sound knowledge of such “tropical” renal diseases is essential for the practicing general pediatrician or nephrologist. This chapter describes tropical renal diseases as broadly divided into “infectious” conditions such as malaria, rickettsial infections, and viral hemorrhagic fevers, among others, and “toxic” conditions including snakebite and use of indigenous medicines which result in renal injury. In general, severe and progressive renal damage is preventable with early diagnosis and treatment of the underlying condition and provision of supportive care.

Acute Lonomia obliqua caterpillar envenomation-induced physiopathological alterations in rats: evidence of new toxic venom activities and the efficacy of serum therapy to counteract systemic tissue damage

The clinical manifestations of Lonomia obliqua caterpillar envenomation are systemic hemorrhage and acute kidney injury. In an effort to better understand the physiopathological mechanisms of envenomation, a rat model was established to study systemic tissue damage during L. obliqua envenomation. An array of acute venom effects was characterized, including biochemical, hematological, histopathological, myotoxic and genotoxic alterations. Rapid increases in serum alanine and aspartate transaminases, γ-glutamyl transferase, lactate dehydrogenase, hemoglobin, bilirubin, creatinine, urea and uric acid were observed, indicating that intravascular hemolysis and liver and kidney damage had occurred. Treatment with a specific antivenom (antilonomic serum) for up to 2 h post-venom injection neutralized the biochemical alterations. However, treatment after 6 h post-venom injection failed to normalize all biochemical parameters, despite its efficacy in reversing coagulation dysfunction. The hematological findings were consistent with hemolytic anemia and neutrophilic leukocytosis. The histopathological alterations were mainly related to hemorrhage and inflammation in the subcutaneous tissue, lung, heart and kidneys. Signs of congestion and hemosiderosis were evident in the spleen, and hemoglobin and/or myoglobin casts were also detected in the renal tubules. Increased levels of creatine kinase and creatine kinase-MB were correlated with the myocardial necrosis observed in vivo and confirmed the myotoxicity detected in vitro in isolated extensor digitorum longus muscles. Significant DNA damage was observed in the kidneys, heart, lung, liver and lymphocytes. The majority of the DNA lesions in the kidney were due to oxidative damage. The results presented here will aid in understanding the pathology underlying Lonomia's envenomation.

Clinical profile, species-specific severity grading, and outcome determinants of snake envenomation: An Indian tertiary care hospital-based prospective study

Objective:

We undertook this study to assess the clinical profile and outcome determinants of different snake envenomation as well as to assign species-specific severity grade to different cases based on clinico – laboratory evidence scale.

Materials and Methods:

A prospective clinico – epidemiologic evaluation for outcome determinants of snakebite envenomation was carried out based on a clinico – laboratory severity grading scale, among 76 patients over a period of 2 years, in a tertiary care hospital in southern India.

Results:

Majority of patients were male agricultural workers (53.9%) followed by housewives (19.7%), and students (9.2%). Occurrence of viper snake envenomation with hemotoxic syndrome (73.68%) was highest followed by cobra and krait envenomation with neurotoxic (19.73%) and hemo – neurotoxic (5.3%) syndrome, respectively. On the contrary, maximum mortality and severity was seen in krait (60%) followed by cobra (13.33%) and viper (8.9%) envenomation. The average dose of anti-snake venom (ASV) administered varied from 9.83 (±7.22) to 20.25 (±4.92) vials throughout grade I to IV in all snake species envenomation. An increase in severity grade, ASV dose, and mortality were observed with the corresponding delay in ‘bite to needle time.’ Also, initial traditional treatments and krait species envenomation were significantly associated with higher grades of severity and mortality.

Conclusion:

There is an urgent need to spread awareness among the community for avoidance of traditional treatment and any delay in medical intervention in snakebite incidents.

Bothrops leucurus venom induces nephrotoxicity in the isolated perfused kidney and cultured renal tubular epithelia

Bites from snake (Bothrops genus) cause local tissue damage and systemic complications, which include alterations such as hemostatic system and acute renal failure (ARF). Recent studies suggest that ARF pathogenesis in snakebite envenomation is multifactorial and involves hemodynamic disturbances, immunologic reactions and direct nephrotoxicity. The aim of the work was to investigate the effects of the Bothrops leucurus venom (BlV) in the renal perfusion system and in cultured renal tubular cells of the type MDCK (Madin-Darby Canine kidney). BlV (10 μg/mL) reduced the perfusion pressure at 90 and 120 min. The renal vascular resistance (RVR) decreased at 120 min of perfusion. The effect on urinary flow (UF) and glomerular filtration rate (GFR) started 30 min after BlV infusion, was transient and returned to normal at 120 min of perfusion. It was also observed a decrease on percentual tubular transport of sodium (%TNa(+)) at 120 min and of chloride (%TCl(-)) at 60 and 90 min. The treatment with BlV caused decrease in cell viability to the lowest concentration tested with an IC(50) of 1.25 μg/mL. Flow cytometry with annexin V and propidium iodide showed that cell death occurred predominantly by necrosis. However, a cell death process may involve apoptosis in lower concentrations. BlV treatment (1.25 μg/mL) led to significant depolarization of the mitochondrial membrane potential and, indeed, we found an increase in the expression of cell death genes in the lower concentrations tested. The venom also evoked an increase in the cytosolic Ca(2+) in a concentration dependent manner, indicating that Ca(2+) may participate in the venom of B. leucurus effect. The characterization of the effects in the isolated kidney and renal tubular cells gives strong evidences that the acute renal failure induced by this venom is a result of the direct nephrotoxicity which may involve the cell death mechanism.

Comparative in-vivo toxicity of venoms from South Asian hump-nosed pit vipers (Viperidae: Crotalinae: Hypnale)

Background

Envenoming by south Asian hump-nosed pit vipers (Genus: Hypnale) is a significant health issue in Sri Lanka and in peninsular India. Bites by these snakes frequently lead to local envenoming, coagulopathy and acute renal failure even resulting in death. Recently the genus was revised and the existence of three species viz H. hypnale, H. nepa and H. zara were recognized. There is, however, a paucity of information on the toxicity of the venoms of these species. Hence, we compared the toxic effects of the three Hypnale venoms using BALB/c mice.

Findings

Intraperitoneal median lethal doses (LD₅₀) for H. hypnale, H. zara and H. nepa venoms were 1.6, 6.0 and 9.5 μg protein/g respectively. Minimum haemorrhagic doses for venoms of H. hypnale, H. zara and H. nepa were 3.4, 11.0 and 16.6 μg protein/mouse respectively. The minimum necrotic doses for the same venoms were 15.0, 55.1 and 68.2 μg protein/mouse respectively. Severe congestion and petecheal haemorrhages were observed in lungs, kidneys, liver and the alimentary tract. Histopathogical examination of kidneys revealed proximal tubular cell injury and acute tubular necrosis with intact basement membrane indicating possible direct nephrotoxicity. Hypnale venoms caused pulmonary oedema, hepatocellular degeneration and necrosis, focal neuronal degeneration in brain and extramedullary haemopoiesis in spleen. H. hypnale venom caused all above histopathological alterations at lower doses compared to the other two.

Conclusion

Hypnale venoms cause similar pathological changes with marked differences in the severity of the toxic effects in vivo. Therefore, differences in the severity of the clinical manifestations could possibly be seen among bite victims of the three Hypnale species.

Cross-neutralisation of the neurotoxic effects of Egyptian cobra venom with commercial tiger snake antivenom

Cross-neutralisation has been demonstrated for haemorrhagic venoms including Echis spp. and Cerastes spp. and for Australia elapid procoagulant toxins. A previous study showed that commercial tiger snake antivenom (TSAV) was able to neutralise the systemic effects of the Egyptian cobra, Naja haje, in vivo but it is unclear if this was true cross-neutralisation. The aim of the current study was to determine whether TSAV can neutralise the in vitro neurotoxic effects of N. haje venom. Both Notechis scutatus (10 μg/ml) and N. haje (10 μg/ml) venoms caused inhibition of indirect (supramaximal V, 0.1 Hz, 0.2 msec.) twitches of the chick biventer cervicis nerve-muscle preparation with t(90) values (i.e. the time to produce 90% inhibition of the original twitch height) of 26 ± 1 min. (n = 4) and 36 ± 4 min.; (n = 4). This effect at 10 μg/ml was significantly attenuated by the prior addition of TSAV (5 U/ml). A comparison of the reverse-phase HPLC profiles of both venoms showed some similarities with peak elution times, and SDS-PAGE analysis elucidated comparable bands across both venoms. Further analysis using Western immunoblotting indicated TSAV was able to detect N. haje venom, and enzyme immunoassay showed that in-house biotinylated polyclonal monovalent N. scutatus antibodies were able to detect N. haje venom. These findings demonstrate cross-neutralisation between different and geographically separated snakes supporting potential immunological similarities in snake toxin groups for a large range of snakes. This provides more evidence that antivenoms could be developed against specific toxin groups to cover a large range of snakes.

[Kidney injury biomarkers]

Over the last few decades, prevalence of renal diseases has grown continuously in occidental societies due to life conditions (age, life style, chronic disease, etc.) or potential exposure to nephrotoxic agents (drugs and environmental chemicals). Today, the knowledge of the nephropatology mechanism is improving. Nevertheless, considering it is a complex and multifunctional structure, the clinical strategy of this issue (prognostic, diagnostic or therapy) keeps posing a major challenge for clinicians mostly because classical markers are not sensitive enough and require hours before reaching significant levels. Furthermore, most of these markers provide information on function and not on structural integrity of the tissue. Identification and development of new biomarkers share promise of improvement in the rapid diagnostic of kidney diseases and development of new cures in order to optimize the clinical strategy associated to the renal failure.

Chronic kidney disease in snake envenomed patients with acute kidney injury in Sri Lanka: a descriptive study

BACKGROUND

Data on the long-term outcomes of acute kidney injury (AKI) in envenomed patients leading to chronic kidney disease (CKD) are scarce. The aim of the study was to investigate this issue and to determine the predictive factors in developing CKD.

METHODS

The records of a series of 54 patients who had AKI following a snakebite during the period 2004-2009 and who had been followed up were reviewed in the nephrology unit, Kandy, Sri Lanka. The primary outcome measure was the failure of renal functions to return to normal within 1 year. The renal histology was studied in seven patients.

RESULTS

The mean age of the group was 50 years (SD 13 years) and 39 (72%) patients were men. The offending snakes were Russell's viper and hump-nosed viper in 15 (28%) and 13 (24%) patients, respectively. At 1 year, 20 patients (37%) had developed CKD (CKD group) and the rest (63%) had recovered (recovered group). The acute stage serum creatinine was high in both groups with no difference (on admission, p=0.134; on discharge, p=0.323), but the CKD group showed significantly high serum creatinine at 2 months after AKI (p=0.004). Mean duration of renal replacement therapy (RRT) of the recovered group and CKD group were 7 (SD 5) and 16 (SD 12) days, respectively (p=0.015). Renal histology of six CKD patients showed predominant glomerular sclerosis and interstitial nephritis.

CONCLUSIONS

CKD is an outcome of severe AKI following snake envenoming probably predicted by the length of RRT.

Renal cortical necrosis, peripheral gangrene, perinephric and retroperitoneal haematoma in a patient with a viper bite

Snakebites are estimated to affect more than 2.5 million people annually, of whom more than 100,000 die. Viper bites cause various systemic symptoms such as: coagulopathy; haemolysis; acute renal failure; a generalized increase in capillary permeability; rhabdomyolysis; and neurotoxicity. Wide spectrums of vascular complications are seen. We report the case of a patient developing gangrenous changes in a lower limb along with the development of perinepheric and retroperitoneal haematoma with acute cortical necrosis of the kidneys.

Inflammatory mediators release in urine from mice injected with Crotalus durissus terrificus venom

In this study, we investigated in groups of female BALB/c mice injected with Crotalus durissus terrificus venom (Cdt) the renal function based on creatinine clearance, percentage of fractional excretion cytokines and histological examination of renal tissue. Cdt caused renal alterations that induced proteinuria during the initial hours post-venom and reduced creatinine clearance 15 min. up to 2 hours post-venom administration. In urine from mice injected with Cdt induced a decrease in IL-4 levels. More pronounced increments of IL-5, IL-6 and IFN-γ were observed after 15 and 30 min, respectively. The highest levels of TNF and IL-10 were observed at 1 and 4 hs, respectively. The ratios of pro- and anti-inflammatory cytokines in animals injected with Cdt, which may be manifested in the inflammatory status during the envenoming. In groups of animals treated with Cdt were observed a decreasing in creatinine clearance and its effect on glomerular filtration rate was accompanied by decreased fractional excretion of cytokines and morphologic disturbances. This loss of change selectively in envenomation could thus explain why the relatively excretion of cytokines is reduced while of total proteins increases. In conclusion the fractional excretion of cytokines is significantly reduced in mice injected with Cdt, despite proteinuria.

Allopurinol reduces the lethality associated with acute renal failure induced by Crotalus durissus terrificus snake venom: comparison with probenecid

Background

Acute renal failure is one of the most serious complications of envenoming resulting from Crotalus durissus terrificus bites. This study evaluated the relevance of hyperuricemia and oxidative stress and the effects of allopurinol and probenecid in renal dysfunction caused by direct nephrotoxicity of C. d. terrificus venom.

Methodology/Principal Findings

Hematocrit, protein, renal function and redox status were assessed in mice. High ratio of oxidized/reduced glutathione and hyperuricemia induced by C. d. terrificus venom were ameliorated by both, allopurinol or probenecid, but only allopurinol significantly reduced the lethality caused by C. d. terrificus venom. The effectiveness of probenecid is compromised probably because it promoted hypercreatinemia and hypocreatinuria and worsed the urinary hypo-osmolality in envenomed mice. In turn, the highest effectiveness of allopurinol might be due to its ability to diminish the intracellular formation of uric acid.

Conclusions/Significance

Data provide consistent evidences linking uric acid with the acute renal failure induced by C. d. terrificus venom, as well as that this envenoming in mice constitutes an attractive animal model suitable for studying the hyperuricemia and that the allopurinol deserves to be clinically evaluated as an approach complementary to anti-snake venom serotherapy.

In Brazil, among registered snake bites, those by the genus Crotalus originate the highest mortality rate. The rattlesnake Crotalus durissus terrificus is the most frequently implicated in these accidents. The kidney is a particularly vulnerable organ to the venom of this rattlesnake. In fact, the most serious complication of Crotalus snake bite is the renal dysfunction, and among the fatal cases of Crotalus bites in Brazil 5% are patients treated with antivenom. The hyperuricemia has been observed in human accidents with snake venoms, but this parameter has not received any special attention as a relevant factor in the etiology of renal dysfunction caused by these venoms. This study examined the effects of treatments with low-cost and low-risk uricostatic (allopurinol) and uricosuric (probenecid) drugs on the envenomation by C. d. terrificus, showing that allopurinol and probenecid mitigated certain nephrotoxic effects, as well as the survival of envenomed mice was improved through the effects of allopurinol on reduction of oxidative stress and intracellular formation of uric acid. This new knowledge provides consistent evidences linking uric acid with the renal dysfunction induced by rattlesnake bites and that the allopurinol deserves to be clinically evaluated as an approach complementary to anti-snake venom serotherapy.

Acute kidney injury in the tropics

Acute kidney injury (AKI) is one of the most challenging problems faced by clinicians in the tropics owing to its fast-changing burden. AKI in the tropics is strikingly different from that in the developed world in terms of etiology and presentation. In addition, there is a stark contrast between well-developed and poor areas in the tropics. The true epidemiological picture of AKI in the tropics is not well understood due to the late presentation of patients to tertiary centers. Infections remain the major culprit in most cases of AKI, with high mortality rates in the tropics. Human immunodeficiency virus-related AKI, related to nephrotoxicity due to antiretroviral therapy, is on the rise. Acute tubular necrosis and thrombotic microangiopathy are the most common mechanisms of AKI. A notable problem in the tropics is the scarcity of resources in health centers to support patients who require critical care due to AKI. This article reviews the unique and contrasting nature of AKI in the tropics and describes its management in each situation.

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.

Burden of chronic kidney disease: an international perspective

CKD is associated with increased cardiovascular mortality and a loss of disability-adjusted life years. Diseases of the genitourinary system were responsible for 928,000 deaths and 14,754,000 disability-adjusted life years in 2004. However, the absence of kidney registries in most of the low- and middle-income countries has made it difficult to ascertain the true burden of CKD in these countries. The global increase in the incidence and prevalence of CKD is being driven by the global increase in the prevalence of diabetes mellitus, hypertension, obesity, and aging. Most patients in low- and middle-income countries die because they cannot access renal replacement therapy because of the exorbitant cost. Community surveys have shown that the number of people with end-stage kidney disease is just the tip of the "CKD iceberg." The preventive strategies to stem the tide of CKD should involve educating the population on how to prevent renal disease; identifying those at risk of developing CKD; raising the awareness of the general public, policy makers, and health care workers; modifying the lifestyle of susceptible individuals; detecting early stage of CKD; arresting or hindering the progression of disease; and creating facilities for global assistance.

Non-drug-induced nephrotoxicity

Several drugs and other compounds can induce acute and/or chronic nephrotoxicity. The goal of this study was to review clinical features of nephrotoxicity induced by 'atypical' or 'unconventional' agents, such as environmental agents (metals, minerals, animals), food agents (mushrooms, aristolochic acid, medicinal traditional herbals, dietary supplements, melamine), drugs, and other products (ethylene glycol). Nephrotoxicity varies according to local background, dependent on different food and cultural customs, as well as to differences in local fauna and flora. The incidence of such a phenomenon is not well known. Many different pathophysiological pathways are involved, and the spectrum of renal lesions is rather wide. 'Epidemic nephrotoxicity' may occur, as recently illustrated by the melamine epidemics in Chinese infants receiving powdered milk formulas; a rapid reaction to unusual increased frequency of acute kidney injury and nephrolithiasis in young children has led to a rapid analysis from international experts, with subsequent recommendations for diagnosis and care. Nephrotoxicity should be considered when there is any unexplained renal impairment, especially in children.

Asian leadership in chronic kidney disease

Asian Pacific countries include those with the highest incidence of renal failure in the world, the richest and poorest economies and unparalleled diversity of economy, culture and geography. From this come many challenges, but also a strong basis for the introduction of strategies to combat renal diseases. With a rapidly developing scientific community, Asia needs to accept the challenge of becoming a global leader in nephrology in the near future.

Snakebite nephrotoxicity in Asia

Snakebites have the highest incidence in Asia and represent an important health problem. Clinical renal manifestations include proteinuria, hematuria, pigmenturia, and renal failure. Nephropathy usually is caused by bites by snakes with hemotoxic or myotoxic venoms. These snakes are Russell's viper, saw-scaled viper, hump-nosed pit viper, green pit viper, and sea-snake. Renal pathologic changes include tubular necrosis, cortical necrosis, interstitial nephritis, glomerulonephritis, and vasculitis. Hemodynamic alterations caused by vasoactive mediators and cytokines and direct nephrotoxicity account significantly for the development of nephropathy. Hemorrhage, hypotension, disseminated intravascular coagulation, intravascular hemolysis, and rhabdomyolysis enhance renal ischemia leading to renal failure. Enzymatic activities of snake venoms account for direct nephrotoxicity. Immunologic mechanism plays a minor role.

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.