Envenomed Patients Research Articles

Point-of-care infrared thermal imaging for differentiating venomous snakebites from non-venomous and dry bites.

Local envenomation following snakebites is accompanied by thermal changes, which could be visualized using infrared imaging. We explored whether infrared thermal imaging could be used to differentiate venomous snakebites from non-venomous and dry bites. We prospectively enrolled adult patients with a history of snakebite in the past 24 hours presenting to the emergency of a teaching hospital in southern India. A standardized clinical evaluation for symptoms and signs of envenomation including 20-minute whole-blood clotting test and prothrombin time was performed to assess envenomation status. Infrared thermal imaging was done at enrolment, 6 hours, and 24 hours later using a smartphone-based device under ambient conditions. Processed infrared thermal images were independently interpreted twice by a reference rater and once by three novice raters. We studied 89 patients; 60 (67%) of them were male. Median (IQR) time from bite to enrolment was 11 (6.5-15) hours; 21 (24%) patients were enrolled within 6 hours of snakebite. In all, 48 patients had local envenomation with/without systemic envenomation, and 35 patients were classified as non-venomous/dry bites. Envenomation status was unclear in six patients. At enrolment, area of increased temperature around the bite site (Hot spot) was evident on infrared thermal imaging in 45 of the 48 patients with envenomation, while hot spot was evident in only 6 of the 35 patients without envenomation. Presence of hot spot on baseline infrared thermal images had a sensitivity of 93.7% (95% CI 82.8% to 98.7%) and a specificity of 82.9% (66.3% to 93.4%) to differentiate envenomed patients from those without envenomation. Interrater agreement for identifying hot spots was more than substantial (Kappa statistic >0.85), and intrarater agreement was almost perfect (Kappa = 0.93). Paradoxical thermal changes were observed in 14 patients. Point-of-care infrared thermal imaging could be useful in the early identification of non-venomous and dry snakebites.

Association of cfDNA levels and bothrops envenomation

In the Amazon, around 90% of snakebites are caused by the Bothrops genus. Complications arising from Bothrops envenomations result from the inflammatory and coagulotoxic activities of the venom. The aim of this study was to investigate the potential of cell-free DNA (cfDNA) as a biomarker of severity in Bothrops snakebites. Patients were treated at the Fundação de Medicina Tropical Dr. Heitor Vieira Dourado (FMT-HVD), Manaus, in the Brazilian Amazon. cfDNA plasma levels were measured by amplifying the human telomerase reverse transcriptase (hTERT) sequence using quantitative RT-PCR. Median levels of cfDNA were compared between envenomed and healthy volunteers and among patients presenting different complications, such as renal failure, bleeding and infection. Of the 76 patients included, 82.9% were male, with a mean age of 32.8 years, and envenomations were mainly classified as severe (39.5%). ROC curve analysis showed a good accuracy of cfDNA levels (AUROC of 0.745) in envenomation diagnosis. A correlation analysis using laboratory variables showed positive correlation with lactate dehydrogenase (p = 0.033) and platelet count (p = 0.003). When cfDNA levels were compared with clinical complications, significant statistical differences were only found among individuals with mild and severe pain (p < 0.05). In summary, our results demonstrated that cfDNA levels are sufficiently accurate for discriminating between envenomed and non-envenomed patients, but are not able to distinguish different complications and the level of severity among envenomed patients. Thus, the role of cfDNA in the pathogenesis of the snakebite envenomations needs to be further investigated.

Bothrops lanceolatus snake (Fer-de-lance) venom triggers inflammatory mediators' storm in human blood.

Systemic increased inflammatory mediators' levels are a hallmark in a plethora of pathological conditions, including thrombotic diseases as the envenomation by Bothrops lanceolatus snake. Multiple organ infarctions, which are not prevented by anticoagulant therapy, are the main cause of death on this envenomation. However, the potential mechanisms involved in these systemic reactions are underexplored. This study aimed to explore the potential systemic events which could contribute to thrombotic reactions on the envenomation by B. lanceolatus in an ex vivo human whole-blood model. B. lanceolatus venom elicited an inflammatory reaction, which was characterized by a strong complement activation, since we detected high C3a, C4a and C5a anaphylatoxins levels. Besides, the venom promoted soluble Terminal Complement Complex (sTCC) assembly. Complement activation was accompanied by intense lipid mediators' release, which included LTB4, PGE2 and TXB2. In addition, in the blood exposed to B. lanceolatus venom, we detected IL-1β, IL-6 and TNF-α interleukins production. Chemokines, including CCL2, CCL5 and CXCL8 were upregulated in the venom presence. These outcomes show that B. lanceolatus venom causes a strong inflammatory reaction in the blood favoring a potential setting to thrombi formation. Thus, inhibiting inflammatory mediators or their receptors may help in the envenomed patients' management.

Hemodynamic Changes Provoked through Intravascular Injection of the Echis carinatus Venom in Rats.

Echis carinatus (E. carinatus) is known for its hematological and nephrotoxic properties in the envenomed patients. Based on the limited data upon the cardiovascular changes associated with this dangerous venomous snake in Iran, the current study purposed to evaluate the venom-induced hemodynamic manifestations in rats. Venom (120 µg/kg) was administered intravenously within one minute through the left femoral vein, and the hemodynamic parameters were continuously recorded using a pressure transducer (MLT844, ADInstruments, Australia). The venom caused prominent hypotension leading to death a few minutes after a transient uprise in blood pressure. It also induced a decrease in heart and pulmonary rates, yet it had no arrhythmogenic properties. Additionally, pre-treatment with the pepsin-derived Iranian polyvalent antivenom (30 µl/Kg) completely neutralized the hemodynamic responses but had no effect when instilled two minutes after venom injection. Heparin (300 IU/kg) and epinephrine (1.5 µg/kg) prevented dramatic hypotension when used 10 minutes before venom instillation; however, atropine (1 mg/kg), dexamethasone (1 mg/kg), and ketorolac (10 mg/ml) had no effects. All treated rats were killed post-injection. Histologically, the lung was the most vulnerable organ with mononuclear infiltration, microcystic formation, and significant capillary congestion. Prominent renal pathological deterioration also occurred, including mesangial cell infiltration and diffuse bleeding, leading to acute tubular necrosis. Modest portal inflammation and vascular congestion were observed in the hepatic tissue of the envenomed rats. The crude venom of Iranian Echis carinatus caused hypotension leading to bradycardia, a decrease in pulmonary rate, and death without significant histological changes to the heart.

Demographic and Laboratory characteristics variations among snake envenomation patients- An Institutional study

Demographic and Laboratory characteristics variations among snake envenomation patients- An Institutional study

Circulating Secretory Phospholipase A2 Activity following Snakebites and Its Relationship with Envenomation Status and Progression of Local Swelling.

We studied whether circulating secretory phospholipase A2 (sPLA2) activity reliably distinguished patients with snakebite envenomation from those with nonvenomous/dry snakebites, and whether patients with progressive local swelling had persistence of circulating sPLA2 activity despite antivenom treatment. We prospectively enrolled adults presenting to the emergency with a history of snakebite in the past 24 hours. We estimated circulating sPLA2 activity at baseline before antivenom administration and after 48 hours in those with envenomation. We enrolled 52 patients with snakebites (mean age 39.3 ± 12.6 years; 35 [67%] men), and 16 patients with infective cellulitis as controls. Thirty patients had local ± systemic envenomation; 15 were classified as dry/nonvenomous bites; and envenomation status was unclear in seven patients. Baseline sPLA2 activity was significantly higher in snakebite patients than that in those with infective cellulitis (4.64 [3.38-5.91] versus 3.38 [1.69-4.01] nmol/minute/mL; P = 0.005). Among patients with snakebites, sPLA2 activity in the highest quartile was significantly associated with envenomation (12 of 27 versus two of 22; P = 0.010). However, median sPLA2 activity did not differ significantly between patients with envenomation and the rest. Baseline sPLA2 activity was significantly associated with the maximum extent of limb swelling (P = 0.031 for trend). In envenomed patients, circulating sPLA2 activity significantly decreased after 48 hours compared with the baseline (5.49 [3.38-8.86] versus 3.38 [2.53-4.64]; P = 0.003) including those with progressive swelling. Although circulating sPLA2 activity was elevated following snakebites, its sensitivity to diagnose envenomation appears to be limited. Administration of more antivenom after systemic manifestations had reversed might not benefit patients with progressive local swelling.

In-Vitro Neutralization of the Neurotoxicity of Coastal Taipan Venom by Australian Polyvalent Antivenom: The Window of Opportunity.

Coastal taipan (Oxyuranus scutellatus) envenoming causes life-threatening neuromuscular paralysis in humans. We studied the time period during which antivenom remains effective in preventing and arresting in vitro neuromuscular block caused by taipan venom and taipoxin. Venom showed predominant pre-synaptic neurotoxicity at 3 µg/mL and post-synaptic neurotoxicity at 10 µg/mL. Pre-synaptic neurotoxicity was prevented by addition of Australian polyvalent antivenom before the venom and taipoxin and, reversed when antivenom was added 5 min after venom and taipoxin. Antivenom only partially reversed the neurotoxicity when added 15 min after venom and had no significant effect when added 30 min after venom. In contrast, post-synaptic activity was fully reversed when antivenom was added 30 min after venom. The effect of antivenom on pre-synaptic neuromuscular block was reproduced by washing the bath at similar time intervals for 3 µg/mL, but not for 10 µg/mL. We found an approximate 10–15 min time window in which antivenom can prevent pre-synaptic neuromuscular block. This time window is likely to be longer in envenomed patients due to the delay in venom absorption. Similar effectiveness of antivenom and washing with 3 µg/mL venom suggests that antivenom most likely acts by neutralizing pre-synaptic toxins before they interfere with neurotransmission inside the motor nerve terminals.

Phospholipase A2 (PLA2) as an Early Indicator of Envenomation in Australian Elapid Snakebites (ASP-27).

Early diagnosis of snake envenomation is essential, especially neurotoxicity and myotoxicity. We investigated the diagnostic value of serum phospholipase (PLA2) in Australian snakebites. In total, 115 envenomated and 80 non-envenomated patients were recruited over 2 years, in which an early blood sample was available pre-antivenom. Serum samples were analyzed for secretory PLA2 activity using a Cayman sPLA2 assay kit (#765001 Cayman Chemical Company, Ann Arbor MI, USA). Venom concentrations were measured for snake identification using venom-specific enzyme immunoassay. The most common snakes were Pseudonaja spp. (33), Notechis scutatus (24), Pseudechis porphyriacus (19) and Tropidechis carinatus (17). There was a significant difference in median PLA2 activity between non-envenomated (9 nmol/min/mL; IQR: 7–11) and envenomated patients (19 nmol/min/mL; IQR: 10–66, p < 0.0001) but Pseudonaja spp. were not different to non-envenomated. There was a significant correlation between venom concentrations and PLA2 activity (r = 0.71; p < 0.0001). PLA2 activity was predictive for envenomation; area under the receiver-operating-characteristic curve (AUC-ROC), 0.79 (95% confidence intervals [95%CI]: 0.72–0.85), which improved with brown snakes excluded, AUC-ROC, 0.88 (95%CI: 0.82–0.94). A cut-point of 16 nmol/min/mL gives a sensitivity of 72% and specificity of 100% for Australian snakes, excluding Pseudonaja. PLA2 activity was a good early predictor of envenomation in most Australian elapid bites. A bedside PLA2 activity test has potential utility for early case identification but may not be useful for excluding envenomation.

Enzyme immunoassays for detection and quantification of venoms of Sri Lankan snakes: Application in the clinical setting.

BackgroundDetection and quantification of snake venom in envenomed patients’ blood is important for identifying the species responsible for the bite, determining administration of antivenom, confirming whether sufficient antivenom has been given, detecting recurrence of envenoming, and in forensic investigation. Currently, snake venom detection is not available in clinical practice in Sri Lanka. This study describes the development of enzyme immunoassays (EIA) to differentiate and quantify venoms of Russell’s viper (Daboia russelii), saw-scaled viper (Echis carinatus), common cobra (Naja naja), Indian krait (Bungarus caeruleus), and hump-nosed pit viper (Hypnale hypnale) in the blood of envenomed patients in Sri Lanka.Methodology / Principal findingsA double sandwich EIA of high analytical sensitivity was developed using biotin-streptavidin amplification for detection of venom antigens. Detection and quantification of D. russelii, N. naja, B. caeruleus, and H. hypnale venoms in samples from envenomed patients was achieved with the assay. Minimum (less than 5%) cross reactivity was observed between species, except in the case of closely related species of the same genus (i.e., Hypnale). Persistence/ recurrence of venom detection following D. russelii envenoming is also reported, as well as detection of venom in samples collected after antivenom administration. The lack of specific antivenom for Hypnale sp envenoming allowed the detection of venom antigen in circulation up to 24 hours post bite.ConclusionThe EIA developed provides a highly sensitive assay to detect and quantify five types of Sri Lankan snake venoms, and should be useful for toxinological research, clinical studies, and forensic diagnosis.

Echocardiography versus cardiac biomarkers for myocardial dysfunction in children with scorpion envenomation: An observational study from tertiary care center in northern India.

ObjectiveThis study was done to evaluate myocardial function by 2D Echocardiography and Cardiac biomarkers (cTnI, CK-MB, BNP) changes in patients of scorpion envenomation of grade II-IV and correlate mortality of envenomed children with myocardial dysfunction. MethodsA total of 40 patients admitted consecutively with grade II and more scorpion envenomation from October 2015 to July2018 were enrolled in the study. The data included demographics, the time of presentation, clinical features, echocardiographic findings, electrocardiographic findings, cardiac biomarker levels at admission and discharge, use of inotropic medication, oral prazosin, time of discharge, and their outcome. ResultsThe most common ECG abnormality was sinus tachycardia 28 (70%) followed by low voltage complex 13 (32.5%) which got normalized at the time of discharge in majority. Cardiac troponin I (cTnI) levels were more than 0.1 ng/mL, suggesting myocarditis was present in 25 (62.5%) and got normalized at discharge. CK-MB levels were increased in 26 (65%) patients suggesting myocardial involvement. BNP levels were also increased in 24 (60%) patients suggesting heart failure and its value got normalized at discharge. Abnormal 2D Echo findings as reduced left ventricular ejection fraction (LVEF) was present in 18 (45%) cases suggesting myocardial dysfunction and became normal at discharge. The sensitivity, specificity, positive predictive value and negative predictive value of Cardiac troponin I (cTnI) considering ECHO cardiograph as gold standard were 100, 68.1, 72 and 100% respectively. One patient had died whose Ejection fraction was less than 30%. ConclusionEchocardiography and cTnI can identify subgroup of patients, who require early aggressive therapy. Echocardiography, if not available, cardiac troponin I level can guide early therapy and indicates the prognosis.

Cost of Manufacturing for Recombinant Snakebite Antivenoms.

Snakebite envenoming is a neglected tropical disease that affects millions of people across the globe. It has been suggested that recombinant antivenoms based on mixtures of human monoclonal antibodies, which target key toxins of medically important snake venom, could present a promising avenue toward the reduction of morbidity and mortality of envenomated patients. However, since snakebite envenoming is a disease of poverty, it is pivotal that next-generation therapies are affordable to those most in need; this warrants analysis of the cost dynamics of recombinant antivenom manufacture. Therefore, we present, for the first time, a bottom-up analysis of the cost dynamics surrounding the production of future recombinant antivenoms based on available industry data. We unravel the potential impact that venom volume, abundance of medically relevant toxins in a venom, and the molecular weight of these toxins may have on the final product cost. Furthermore, we assess the roles that antibody molar mass, manufacturing and purification strategies, formulation, antibody efficacy, and potential cross-reactivity play in the complex cost dynamics of recombinant antivenom manufacture. Notably, according to our calculations, it appears that such next-generation antivenoms based on cocktails of monoclonal immunoglobulin Gs (IgGs) could be manufacturable at a comparable or lower cost to current plasma-derived antivenoms, which are priced at USD 13-1120 per treatment. We found that monovalent recombinant antivenoms based on IgGs could be manufactured for USD 20-225 per treatment, while more complex polyvalent recombinant antivenoms based on IgGs could be manufactured for USD 48-1354 per treatment. Finally, we investigated the prospective cost of manufacturing for recombinant antivenoms based on alternative protein scaffolds, such as DARPins and nanobodies, and highlight the potential utility of such scaffolds in the context of low-cost manufacturing. In conclusion, the development of recombinant antivenoms not only holds a promise for improving therapeutic parameters, such as safety and efficacy, but could possibly also lead to a more competetive cost of manufacture of antivenom products for patients worldwide.

What activities do snakebite envenomation patients choose to assess dysfunction?

What activities do snakebite envenomation patients choose to assess dysfunction?

Isolation and pharmacological characterization of α-Elapitoxin-Na1a, a novel short-chain postsynaptic neurotoxin from the venom of the Chinese Cobra (Naja atra)

The Chinese Cobra (Naja atra) is an elapid snake of major medical importance in southern China. Although previous studies have shown that postsynaptic neurotoxins account for 11–23% of N. atra venom, envenomed patients do not display marked signs of neurotoxicity. We have previously shown that the lack of clinical neurotoxicity following snake envenoming by some species with ‘neurotoxic’ venoms may be related to the high prevalence of short-chain postsynaptic neurotoxins in these venoms. In this study, we describe the isolation and characterization of α-Elapitoxin-Na1a (α-EPTX-Na1a; 6949 Da), a short-chain postsynaptic neurotoxin, which accounts for approximately 9% of N. atra crude venom. α-EPTX-Na1a (30–300 nM) produced concentration-dependent inhibition of indirect-twitches, with a t90 value of 17 ± 2 min at 300 nM, and abolished contractile responses to exogenous acetylcholine and carbachol, in the chick biventer cervicis nerve-muscle preparation. The prior addition of either Chinese N. atra monovalent antivenom (0.3 U/ml) or Australian polyvalent snake antivenom (2.4 U/ml), prevented the in vitro neurotoxic effects of α-EPTX-Na1a (30 nM). Addition of each of these antivenoms at the t90 time point partially reversed the in vitro neurotoxicity caused by α-EPTX-Na1a (30 nM). The inhibition of indirect twitches by α-EPTX-Na1a (30 nM) was not reversed by repeatedly washing the tissue. α-EPTX-Na1a displayed pseudo-irreversible antagonism of concentration-response curves to carbachol with a pA2 value of 8.21. De novo protein sequencing of α-EPTX-Na1a revealed a typical short-chain postsynaptic neurotoxin profile of 62 amino acids which shared >98% amino acid sequence similarity with short-chain postsynaptic neurotoxins from other Naja species. When compared to short-chain neurotoxins isolated from cobras in China, α-EPTX-Na1a contained novel residues K47Q (i.e. lysine to glutamine), N48T (i.e. asparagine to threonine) and G49A (i.e. glycine to alanine). In conclusion, α-EPTX-Na1a is a potent, pseudo-irreversible, short-chain neurotoxin. The high prevalence of α-EPTX-Na1a in Chinese N. atra venom is likely to explain the mild neurotoxicity experienced by envenomed patients.

Clinical manifestations and treatments of Protobothrops mucrosquamatus bite and associated factors for wound necrosis and subsequent debridement and finger or toe amputation surgery

Introduction Protobothrops mucrosquamatus bite induces wound necrosis, coagulopathy, thrombocytopenia, rhabdomyolysis, and acute renal failure. The severity of the hematological derangements and associated factors for wound necrosis and subsequent surgery and the appropriate management of these conditions have not been well characterized. Although severe renal failure requiring hemodialysis has been reported following P. mucrosquamatus bite, the culprit snake may be erroneously classified. Materials and methods A total of 186 patients with P. mucrosquamatus bites were retrospectively evaluated. They were categorized into group 1 (patients receiving debridement or finger/toe amputation) and group 2 (all other patients) to identify the associated factors for surgery. Characteristic data were compared between groups 1 and 2 and between definite and suspected cases. Results No differences were observed between definite and suspected cases in terms of symptomatology and management. Of the 186 patients, 7 (3.8%) were asymptomatic, 179 (96.2%) experienced tissue swelling and pain, and 107 (57.5%) had local ecchymosis. Coagulopathy, thrombocytopenia, and renal impairment were found in 13 (7%), 19 (10.2%), and 7 (3.8%) patients, respectively. None of the patients required transfusion therapy or hemodialysis. Furthermore, no systemic bleeding or death occurred. Antivenom was administered to all 179 envenomed patients at a median of 1.5 h post-bite. The median total dose of the specific antivenom was 5.5 vials. In multivariate logistic regression analysis, finger as the bite site, bullae and blister formation, and wound infection were significantly associated with wound necrosis; whereas finger as the bite site and bullae and blister formation were related to debridement or finger/toe amputation. Discussion and conclusions Protobothrops mucrosquamatus envenomation mainly exerts effects on local tissue. Systemic effects are uncommon and generally nonsevere and transient after the treatment with the specific antivenom. We speculated that severe renal failure requiring hemodialysis is not a typical finding of P. mucrosquamatus envenomation. Patients with finger as the bite site and bullae or blister formation should be carefully examined for wound necrosis, secondary infection, and subsequent surgery. Further evaluations of the efficacy of antivenom against local tissue effects and the effect of selective antibiotics in the management of bite wound infection are urgently required. Although the antivenom manufacturer suggested a skin test prior to use, we believed that it could be omitted because it does not accurately predict the allergic responses.

Loxoscelism: Advances and Challenges in the Design of Antibody Fragments with Therapeutic Potential.

Envenoming due to Loxosceles spider bites still remains a neglected disease of particular medical concern in the Americas. To date, there is no consensus for the treatment of envenomed patients, yet horse polyclonal antivenoms are usually infused to patients with identified severe medical conditions. It is widely known that venom proteins in the 30–35 kDa range with sphingomyelinase D (SMasesD) activity, reproduce most of the toxic effects observed in loxoscelism. Hence, we believe that monoclonal antibody fragments targeting such toxins might pose an alternative safe and effective treatment. In the present study, starting from the monoclonal antibody LimAb7, previously shown to target SMasesD from the venom of L. intermedia and neutralize its dermonecrotic activity, we designed humanized antibody V-domains, then produced and purified as recombinant single-chain antibody fragments (scFvs). These molecules were characterized in terms of humanness, structural stability, antigen-binding activity, and venom-neutralizing potential. Throughout this process, we identified some blocking points that can impact the Abs antigen-binding activity and neutralizing capacity. In silico analysis of the antigen/antibody amino acid interactions also contributed to a better understanding of the antibody’s neutralization mechanism and led to reformatting the humanized antibody fragment which, ultimately, recovered the functional characteristics for efficient in vitro venom neutralization.

Severity Grading, Management, Outcome and Epidemiological Profiling of Snakebite Victims in Tertiary Care Hospital in South India: 5 Years Retrospective Study

Objective: We conducted this study to do epidemiological and clinical profiling of the patients with snake bite in a tertiary care referral centre, situated in suburban area of Dakshin Kannada district, Karnataka, south India.Materials and Method: This retrospective, record based study was done by analysing medical records of all the patients of snake bite admitted over 5years from June 2015 to July 2019. It included demographic details and clinical profiling. Based on presenting complaint, clinical sign/symptoms and laboratory reports snake envenomation patients were divided into neurotoxic and hemotoxic group. The severity grading, amount of ASV used and outcome assessed in both the groups.Results: Total 108 patient records were analysed, maximum of which were males (64.8%) in age group of 15-30 years (46.2%). In majority of the cases the species of snake was not identified (67.5%). Dry bites were reported in 40.7% cases, among envenomated cases, 68.7% presented with hemotoxic syndrome, 29.7% with neurotoxic syndrome and 0.9% had both the features. In all envenomated patients with increasing bite to needle time, the grade of severity, amount of used ASV, duration of hospital stay and complications were found to increase.Conclusion: Snake bite is a neglected life threatening condition, which is a preventable disease. Tourniquet is still very commonly used first aid technique, which can be deleterious. The lack of education and awareness about snake bite management was evident and active mass education is clearly needed.

Severity Grading, Management, Outcome and Epidemiological Profiling of Snakebite Victims in Tertiary Care Hospital in South India:5 Years Retrospective Study

Objective: We conducted this study to do epidemiological and clinical profiling of the patients with snake bite in a tertiary care referral centre, situated in suburban area of Dakshin Kannada district, Karnataka, south India. Materials and Method: This retrospective, record based study was done by analysing medical records of all the patients of snake bite admitted over 5years from June 2015 to July 2019. It included demographic details and clinical profiling. Based on presenting complaint, clinical sign/symptoms and laboratory reports snake envenomation patients were divided into neurotoxic and hemotoxic group. The severity grading, amount of ASV used and outcome assessed in both the groups. Results: Total 108 patient records were analysed, maximum of which were males (64.8%) in age group of 15-30 years (46.2%). In majority of the cases the species of snake was not identified (67.5%). Dry bites were reported in 40.7% cases, among envenomated cases, 68.7% presented with hemotoxic syndrome, 29.7% with neurotoxic syndrome and 0.9% had both the features. In all envenomated patients with increasing bite to needle time, the grade of severity, amount of used ASV, duration of hospital stay and complications were found to increase. Conclusion: Snake bite is a neglected life threatening condition, which is a preventable disease. Tourniquet is still very commonly used first aid technique, which can be deleterious. The lack of education and awareness about snake bite management was evident and active mass education is clearly needed.

Envenomation by Trimeresurus stejnegeri stejnegeri: clinical manifestations, treatment and associated factors for wound necrosis.

Background: Trimeresurus stejnegeri stejnegeri bite induces tissue swelling, pain, thrombocytopenia, rhabdomyolysis, and acute renal failure. However, the incidence of coagulopathy, factors associated with wound necrosis, and the appropriate management of this condition have not been well characterized yet.Materials:This study included patients bitten by T. s. stejnegeri that were admitted to the study hospitals from 2001 to 2016. Patient characteristics, laboratory data, and management approaches were compared in victims with and without wound necrosis.Results:A total of 185 patients were evaluated: three patients (1.6%) were asymptomatic; whereas tissue swelling and pain, local ecchymosis, wound necrosis, coagulopathy, thrombocytopenia, rhabdomyolysis, and renal impairment were present in 182, 53, 13, 15, 10, 1, and 3 patients, respectively. One patient died from coagulopathy and hemorrhagic shock. Antivenom was administered to all envenomed patients at a median time of 1.8 h after the bite. The median total dose of antivenom was five vials. Chi-square analysis showed that bitten fingers, using cold packs during first aid, presence of bullae or blisters, lymphangitis or lymphadenitis, local numbness and suspected infection to be significantly associated with wound necrosis. After adjustment using a multivariate logistic regression model, only cold packs as first aid, bulla or blister formation, and wound infection remained significant.Conclusions:The main effects of T. s. stejnegeri envenomation are tissue swelling, pain, and local ecchymosis. We do not recommend the use of cold packs during first aid to reduce wound pain, as this may be a risk factor for wound necrosis. In addition, patients with bulla or blister formation should be carefully examined for subsequent wound necrosis. Antiplatelet use may worsen systemic bleeding. No severe rhabdomyolysis or renal failure was observed in this large case series, we therefore considered that they were not prominent effects of T. s. stejnegeri bite.

Electrocardiography patterns of snake envenomations

Snakebite envenomation constitutes a neglected tropical disease of public health importance. This is evident by over five million persons per year especially young farmers being bitten by snakes in rural areas. Hence, equally making snakebites an occupational disease. Snake envenomation leads to several toxic syndromes including cardiac toxicity. The latter may lead to severe cardiac electrical conductivity disorders with resultant potentially life-threatening cardiac arrhythmias, myocardial infarctions, heart failure and even of cardiac arrest which have been less described. This article aims to describe the electrocardiography dysfunctions caused by snake envenomation to improve the management of snake envenomed patients through early detection, treatment and management of these snake envenomation electrocardiography-related complications.

EVALUATION OF THE EARLY PROGNOSTIC VALUE OF NEUTROPHIL-LYMPHOCYTE RATIO (NLR) AND PLATELET-LYMPHOCYTE RATIO (PLR) IN SNAKEBITE POISONED PATIENTS

Neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) have recently gained popularity as simple, inexpensive, and highly accurate inflammatory markers and they have been suggested as useful predictors for clinical prognosis in critically ill patients in various medical conditions. This study aimed to assess the usefulness of NLR and PLR in predicting the severity of clinical profile and outcome in patients with snake poisoning. Methods: a prospective study from January to August 2016 and a retrospective one from January to December 2015 were conducted on all snake envenomated patients admitted to Poison Control Center of Ain Shams University Hospitals. On admission, complete medical history, physical examination and biochemical laboratory investigations including complete blood count (CBC) and international normalized ratio (INR), were recorded. NLR and PLR were calculated from the differential total leukocyte count (TLC). Outcome data as; intensive care unit (ICU) and hospital stay time, number of anti-venom (NAV) ampoules needed, occurrence of complications and death, were also documented. The patients were classified in to three main groups, according to the degree of severity; Group II (mild grade); Group III (moderate grade) and Group IV (severe grade). In addition to, Group I (control group). Results: 50 patients, 46 males (92%), with mean age (31.54±11.97 years) met inclusion criteria. The frequency of bites in the lower limb was significantly higher than those in the upper limb in all patient groups. There was significant leukocytosis, neutophilia and higher LNR in group III and group IV as compared to group I and group II. Significant lymphocytopenia and thrombocytopenia was evident in group III and group IV as compared to group I and also in group IV compared to group II. INR was statistically higher in group IV in comparison with the other groups. There was significant correlation of NLR level with INR, platelet count, PLR, NAV, ICU stay time and hospital stay time. While, PLR showed non-significant difference between the studied groups as well as non-significant correlation with the outcome parameters. The mortality rate of the study was (2%). Conclusion: High levels of on admission NLR were associated with worse clinical profile and poorer outcome. This was not evident with PLR. NLR was found to function as a new easily calculated readily available biomarker that successfully predicts the prognosis of clinical severity and outcome in snake poisoned patients.