Philodryas patagoniensis bite and local envenoming

A 5-year-old boy bitten by a specimen of Philodryas patagoniensis, a colubrid snake currently classified as nonvenomous, developed signs of local envenoming characterized by swelling and warmth on the bitten limb. This is the first time that local envenoming following Philodryas patagoniensis bite is recognized. Based on the clinical findings and misidentification of the snake, the patient was treated as a victim of Bothrops bite, having received unnecessarily the specific antivenom. Educational efforts to make doctors and health workers capable to identify correctly venomous snakes are necessary, to avoid inappropriate indication of antivenom and decrease the risk of its potentially harmful untoward effects. Examination of the bite site can be useful to the differential diagnosis between pit viper and colubrid bites.

Epidemiological and clinical aspects of snAkebite in Belo Horizonte, Southeast Brazil

Epidemiologic and clinical aspects of 310 hospitalized snakebite patients and 310 matched controls were described, over a seven years period, from an emergency hospital in Belo Horizonte, Southeast Brazil. The diagnosis was based upon clinical picture or actual snake identification. Fifty six percent of victims were bitten by the snakes of genus Bothrops, 32.0% by Crotalus, 1.0% by Lachesis and 10.0% undetermined. During the study period, stable number of cases and marked seasonal variation were noted. In comparing cases of snakebite and controls, those from a rural area or who were involved in agricultural labor activity were identified as a high risk group, with an odds ratio (OR) of 14.7 and 6.7, respectively, in favor of being bitten. Upon treatment, snakebite patients were 13.5 times more likely to have had early anaphylactic reactions than their controls, with a higher association in the age group ³ 20 years (OR = 30.3). Increased risks were also detected for pyrexia (OR = 11.7), with a marked association in the group under 19 years old (OR = 16.6). Severe cases of snakebite are an important treatable cause of morbidity in Brazil but therapy may be potentially life threatening. The higher case-fatality ratio encountered, compared to national statistics may be due the representativeness of the more severe cases who sought hospitalization. Preventing snakebite and early referral of those who are bitten is proposed

Envenomation by the neotropical colubrid Boiruna maculata (Boulenger, 1896): a case report

This is a case report of a Boiruna maculata snake bite in a child admitted to the Hospital Municipal de Pronto Socorro de Porto Alegre, Porto Alegre, RS, Brazil. The patient was bitten on the lower left limb, and exhibited pronounced local manifestations of envenomation. She was treated with Bothrops antivenom and was discharged from the hospital five days later with marked improvement of envenomation.

Envenomation by neotropical Opisthoglyphous colubrid Thamnodynastes cf. pallidus Linné, 1758 (Serpentes:Colubridae) in Venezuela

This is a case report of a "non-venomous" snake bite in a herpetologist observed at the Sciences Faculty of the Universidad de los Andes (Mérida, Venezuela). The patient was bitten on the middle finger of the left hand, and shows signs of pronounced local manifestations of envenomation such as bleeding from the tooth imprint, swelling and warmth. He was treated with local care, analgesics, and steroids. He was dismissed from the hospital and observed at home during five days with marked improvement of envenomation. The snake was brought to the medical consult and identified as a Thamnodynastes cf. pallidus specimen. This report represents the first T. pallidus accident described in a human.

A low-cost method to test cytotoxic effects of Crotalus vegrandis (Serpentes: Viperidae) venom on kidney cell cultures

The pathogenesis of the renal lesion upon envenomation by snakebite has been related to myolysis, hemolysis, hypotension and/or direct venom nephrotoxicity caused by the venom. Both primary and continuous cell culture systems provide an in vitro alternative for quantitative evaluation of the toxicity of snake venoms. Crude Crotalus vegrandis venom was fractionated by molecular exclusion chromatography. The toxicity of C. vegrandis crude venom, hemorrhagic, and neurotoxic fractions were evaluated on mouse primary renal cells and a continuous cell line of Vero cells maintained in vitro. Cells were isolated from murine renal cortex and were grown in 96 well plates with Dulbecco's Modified Essential Medium (DMEM) and challenged with crude and venom fractions. The murine renal cortex cells exhibited epithelial morphology and the majority showed smooth muscle actin determined by immune-staining. The cytotoxicity was evaluated by the tetrazolium colorimetric method. Cell viability was less for crude venom, followed by the hemorrhagic and neurotoxic fractions with a CT50 of 4.93, 18.41 and 50.22 µg/mL, respectively. The Vero cell cultures seemed to be more sensitive with a CT50 of 2.9 and 1.4 µg/mL for crude venom and the hemorrhagic peak, respectively. The results of this study show the potential of using cell culture system to evaluate venom toxicity.

Bites by coral snakes (Micrurus spp.) in Campinas, State of São Paulo, Southeastern Brazil

Coral snakes (Micrurus spp.) are the main representatives of the Elapidae in South America. However, bites by these snakes are uncommon. We retrospectively reviewed the data from 11 individuals bitten by coral snakes over a 20-year period; four were confirmed (snake brought for identification) and seven were highly suspected (neuromuscular manifestations) cases of elapid envenoming. The cases were classified as dry-bite (n = 1, caused by M. lemniscatus; did not receive antivenom), mild (n = 2, local manifestations with no acute myasthenic syndrome; M. frontalis and Micrurus spp.), moderate (n = 5, mild myasthenia) or severe (n = 3, important myasthenia; one of them caused by M. frontalis). The main clinical features upon admission were paresthesia (local, n = 9; generalized, n = 2), local pain (n = 8), palpebral ptosis (n = 8), weakness (n = 4) and inability to stand up (n = 3). No patient developed respiratory failure. Antivenom was used in ten cases, with mild early reactions occurring in three. An anticholinesterase drug was administered in the three severe cases, with a good response in two. No deaths were observed. Despite the high toxicity of coral snake venoms, the prognosis following envenoming is good. In serious bites by M. frontalis or M. lemniscatus, the venom of which acts postsynaptically, anticholinesterases may be useful as an ancillary measure if antivenom is unavailable, if there is a delay in obtaining a sufficient amount, or in those patients given the highest recommended doses of antivenom without improvement of the paralysis or with delayed recovery.

Envenomation by Micrurus coral snakes in the Brazilian Amazon region: report of two cases

Two cases of proven coral snake bites were reported in Belém, Pará State, Brazil. The first case was a severe one caused by Micrurus surinamensis. The patient required mechanical ventilation due to acute respiratory failure. The second case showed just mild signs of envenomation caused by Micrurus filiformis. Both patients received specific Micrurus antivenom and were discharged without further complications. Coral snake bites are scarcely reported in the Amazon region and there is a broad spectrum of clinical manifestations, varying from extremely mild to those which may rapidly lead to death if the patient is not treated as soon as possible.

South American rattlesnake bite and soft-tissue infection: report of a case

The case of a man bitten by a South American rattlesnake (Crotalus durissus) and who developed an abscess at the site of the bite is reported. Abcesses are a rare complication of this type of envenoming, possibly due to the lack of a strong cytotoxic action of Crotalus durissus venom.

Poisoning due to Philodryas olfersii (Lichtenstein, 1823) attended at Restauração Hospital in Recife, State of Pernambuco, Brazil: case report

Few papers have been published on snake bites caused by Philodryas olfersii. We report here the first case identified at the Centro de Assistência Toxicológica do Hospital da Restauração, Recife, State of Pernambuco. This case was described based on medical protocols, interviewing the patient and identifying the animal that caused the bite. The patient presented pain, heat, erythema, edema and ecchymosis, without other laboratory abnormalities or coagulation disorders. The treatment consisted of administration of eight ampoules of antibothropic serum, and post-administration allergenic reactions were observed. The importance of bites by opistoglyph snakes needs to be reconsidered in research and at specialized treatment centers.

Injuries and envenoming by aquatic animals in fishermen of Coxim and Corumbá municipalities, state of Mato Grosso do Sul, Brazil: identification of the causative agents, clinical aspects and first aid measures

INTRODUCTION: The fishes of continental Brazil have socioeconomic importance due to their potential for sport fishing and commercial and subsistence uses, as seen in the Upper Paraguay River Basin, particularly in the municipalities of the Pantanal region, where it is the second largest economic activity. Injuries caused in professional fishermen are common and poorly studied, as in other regions of the country. METHODS: Data were obtained from questionnaires and interviews with 100 professional fishermen, 50 in each municipality, between December 2008 and October 2009. RESULTS: All the fishermen reported some kind of injury caused by fish stings (78% of injuries) and fish, alligator and snake bites (22%) on the hands (46% of cases) and feet (35% of cases). Most of the patients had mild symptoms. The most severe cases were associated with secondary bacterial infections and required specific treatment and prolonged recovery associated with social and economic losses. CONCLUSIONS: The results of this study indicate that the stressful work conditions, inattention to basic preventive measures and carelessness were factors that contributed to accidents and that the toxicity and ability to inflict mechanical trauma of some aquatic species, plus the ineffective use of first aid and hospital treatment, contributed to the high morbidity and complications in many cases. Data from this study are relevant to the fishing communities of the Pantanal region, since they reveal high rates of accidents, lack of knowledge concerning first aid, initial treatment, injury prevention and lack of medical follow-up of the population.

Comparison of Bothropoides jararaca bites with and without envenoming treated at the Vital Brazil Hospital of the Butantan Institute, State of São Paulo, Brazil

INTRODUCTION: This study analyses the cases of all bites (including dry bites) caused by Bothropoides jararaca attended at the Vital Brazil Hospital of the Butantan Institute, State of São Paulo, Brazil. METHODS: A retrospective study was conducted of patients bitten by Bothropoides jararaca (n=792) from January 1990 to December 2004. The characteristics of the snake specimen, data related to the accident and clinical manifestations on admission were obtained from patient medical records. RESULTS: The majority of the cases in this study were caused by female and juvenile snakes. No stomach contents were found in 93.4% of the snake specimens after dissection. No statistical difference was observed between the occurrence of dry bites and the maturity or sex of the snake. The median SVL of snakes in mild and moderate cases was 40.5cm and in severe cases, SVL increased to 99cm. Necrosis was more common in the digits of the feet and hands (4.8%) compared to the other body regions (1.8%). A significant difference was verified between severity and a time interval greater than six hours from the bite to hospital admission. A significant association was verified between gingival bleeding and abnormal blood coagulability. In accidents caused by adult snakes, necrosis was more frequent (7.2%) compared to accidents caused by juvenile snakes (1%). CONCLUSIONS: In this work, the association between certain epidemiological data and the evolution of biological parameters in the clinical course of Bothrops sensu latu accidents were highlighted, contributing to the improvement of snake bite assistance.

Accidents caused by Bothrops and Bothropoides in the State of Paraiba: epidemiological and clinical aspects

INTRODUCTION: Bothrops and Bothropoides snakes cause 70% of the ophidic accidents in Brazil. The species that cause ophidic accidents in State of Paraíba are Bothropoides erythromelas, Bothrops leucurus and Bothropoides neuwiedi. METHODS: This is a prospective and transverse study, following a quantitative approach of accidents involving Bothrops and Bothropoides admitted to the Toxicological Assistance and Information Centers of Campina Grande and João Pessoa (Ceatox-CG and Ceatox-JP), aimed at identifying the epidemiological and clinical profile of such accidents. All of the patients admitted had medical diagnoses and were monitored at Ceatox-CG or Ceatox-JP. RESULTS: The genera Bothrops and Bothropoides caused 91.7% of the ophidic accidents reported. Snake bites were frequent in men (75.1%), rural workers (65.1%), literate individuals (69%) between 11 and 20 years-old (21.7%), and toes the most common area attacked (52.7%). Most (86.6%) patients were admitted within 6 hours after the accident/bite, with a predominance of mild cases (64.6%). The annual occurrence in Paraíba was 5.5 accidents/100,000 inhabitants and lethality was 0.2%. CONCLUSIONS: Positive changes in the profiles of these accidents were verified, such as the non-application of inadequate solutions, including the use of tourniquet, coffee grounds, garlic, suction and/or cutting the bitten area. Moreover, the Itinerant Laboratory project, linked to Paraíba State University in partnership with Ceatox-CG, has contributed positively, providing several cities of the state with information regarding the prevention of accidents involving venomous animals. The local press has also contributed, reporting the educational work developed by the centers.

Bilateral posterior circulation stroke secondary to a crotalid envenomation: case report

Snake bite envenoming is a disease with potential serious neurological complications. We report a case of an adolescent who was bitten by a rattlesnake and developed bilateral posterior circulation stroke. The rattlesnake was later identified as being Crotalus durissus terrificus. Stroke was probably due to toxic vasculitis or toxin-induced vascular spasm and endothelial damage.

Snakebites as a largely neglected problem in the Brazilian Amazon: highlights of the epidemiological trends in the State of Amazonas

Envenoming snakebites are thought to be a particularly important threat to public health worldwide, especially in rural areas of tropical and subtropical countries. The true magnitude of the public health threat posed by snakebites is unknown, making it difficult for public health officials to optimize prevention and treatment. The objective of this work was to conduct a systematic review of the literature to gather data on snakebite epidemiology in the Amazon region and describe a case series of snakebites from epidemiological surveillance in the State of Amazonas (1974-2012). Only 11 articles regarding snakebites were found. In the State of Amazonas, information regarding incidents involving snakes is scarce. Historical trends show an increasing number of cases after the second half of the 1980s. Snakebites predominated among adults (20-39 years old; 38%), in the male gender (78.9%) and in those living in rural areas (85.6%). The predominant snake envenomation type was bothropic. The incidence reported by the epidemiological surveillance in the State of Amazonas, reaching up to 200 cases/100,000 inhabitants in some areas, is among the highest annual snakebite incidence rates of any region in the world. The majority of the cases were reported in the rainy season with a case-fatality rate of 0.6%. Snakebite envenomation is a great disease burden in the State of Amazonas, representing a challenge for future investigations, including approaches to estimating incidence under-notification and case-fatality rates as well as the factors related to severity and disabilities.

Polychromatism of populations of Corallus hortulanus (Squamata: Boidae) from the southern Amazon Basin, Brazil

The Amazon tree boa Corallus hortulanus is known for featuring a wide variation in color pattern and design markings. Although there are studies on its polychromatism, none of them addresses the geographic variation in the color pattern of this species. The aim of this study was to describe the chromatic variation found in the populations of C. hortulanus from the southern Amazon Basin and its relationship with geographic distribution of the species. Analysis of both design markings and color patterns on 112 C. hortulanus specimens from the southern Amazon Basin interfluves resulted in the identification of six distinct morphotypes. Grayish-brown coloration and elongated diamond-shaped patterns were the most frequent patterns. Two morphotypes showed a tendency of correlation with the geographical distribution of those species found in Madeira and Juruá Rivers. The small sample size does not allow for a robust conclusion on the possible cause of geographic variation. The distribution of morphological patterns of C. hortullanus in the Amazon Basin suggest that there is gene flow between populations, regardless of geographical distance and natural barriers. The variation in color pattern and markings may represent a phenotypic response to the characteristics of different habitats occupied by the species.