Prophylactic Antibiotics Are Not Needed Following Rattlesnake Bites

Clinical Management of North American Snake and Marine Envenomations

Envenomations are the 23rd most common reason for calls to US poison control centers, with over 35,000 incidents reported annually. Snake bites account for over 20% of those calls, while marine envenomations are likely underreported at 3% to 4%.1 While these types of envenomations may not be encountered on a daily basis for many physicians, the different types of envenomations warrant unique management strategies based on the offending creature and symptom presentation. This text serves as a review of the epidemiology, clinical presentations, and management of endemic North American species of snakes and marine vertebrate and invertebrate envenomations.

Infections following rattlesnake envenomation and use of antibiotics

BACKGROUND

There are 7000-8000 venomous snake bites annually in the USA. Antibiotics are commonly administered to bite victims because infection is difficult to differentiate from local tissue injury following envenomation.

METHODS

The Arizona Poison and Drug Information Center (APDIC) in Tucson oversees antivenom administration for 14 Arizona counties. Records (1999-2021) were searched for antibiotic use and confirmed infections after a rattlesnake bite.

RESULTS

There were 4160 calls to APDIC regarding rattlesnakes. After excluding bites to animals, 'dry bites', prisoners and records with missing data, 2059 records were evaluated. Systemic antibiotics were administered to 206 patients (10% of bite victims). Twenty patients (0.97%) had confirmed infections, including cellulitis (n=10), fasciitis (n=4), abscess (n=3) and osteomyelitis (n=3). Five of the victims had positive blood cultures. The presence of tissue necrosis, leukocytosis, fever and elevated fibrinogen levels did not discriminate between toxic effects of venom and infection.

CONCLUSIONS

Confirmed infections following a rattlesnake bite are uncommon (0.97% of bites). Physicians should refrain from prescribing antibiotics, as they are not justified for most rattlesnake bite victims and the variety of pathogens encountered precludes use of any single effective antibiotic.

Suspected envenomation by the common European adder (Vipera berus berus) in 28 horses in Finland

Vipera berus berus is the only venomous snake present in the Nordic countries and cases of envenomation in horses are reported during the warmer months. Little is known about the presentation, treatment and survival of horses with common European adder envenomation. Clinical and laboratory findings, treatment and outcome are reported for 28 horses admitted to Helsinki University Equine Hospital in 2008-2023 due to suspicion of snake bite. Eleven of these horses received antivenom treatment. Other common treatments included non-steroidal anti-inflammatories (22/28), antimicrobials (19/28), intravenous fluid therapy (11/28), corticosteroids (9/28) and local treatment (11/28). All horses survived until discharge. No difference was detected in the length of hospital stay between horses with moderate envenomation that had or had not received antivenom treatment. Horses with moderate envenomation are more likely to receive antivenom treatment and require longer hospital stay than horses with mild envenomation. Antivenom treatment is not associated with shorter hospital stay. Little evidence supports the use of corticosteroids and antibiotics in treatment of envenomation. Studies with larger numbers of animals are warranted to evaluate the effect of treatment, including administration of antivenom, on long-term outcome and survival from envenomation.

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.

The Incidence of Infection Complicating Snakebites in Tropical Australia: Implications for Clinical Management and Antimicrobial Prophylaxis

Objective

To define the incidence of infection following snakebite in tropical Australia and the resulting implications for the routine prescription of prophylactic antibiotics.

Methods

A retrospective study of all individuals presenting to Cairns Hospital, a tertiary referral hospital in tropical Australia, after a snakebite between December 2013 and October 2020.

Results

There were 732 hospitalisations, 720 (98.4%) patients presented within 8 hours of the snakebite, and 29/732 (4.0%) were envenomated. Envenomated patients were more likely to receive empirical antibiotics than nonenvenomated patients (8/29 (27.6%) versus 14/703 (2.0%), p < 0.001), although this was frequently as a bundle of care for critically ill individuals. Superficial skin infection was diagnosed by clinicians in 6/732 (0.8%) patients during their hospitalisation; infection was diagnosed more commonly in envenomated than in nonenvenomated patients (3/29 (10.3%) versus 3/703 (0.4%), p = 0.001). All 3 envenomated individuals diagnosed with infection were believed to have taipan (genus Oxyuranus) bites. Five (83%) of the six patients diagnosed with infection had received empirical antibiotics at presentation; only 1/710 (0.1%) patients who received no antibiotics developed a (superficial) infection.

Conclusion

Infection is a very uncommon complication of snakebite in tropical Australia. Individuals bitten by snakes in tropical Australia should not routinely receive antibiotic prophylaxis.

Antibiotic susceptibility of cultivable microbiota from the oral cavity of captive Bothrops atrox and Bothrops lanceolatus: Implications for the treatment of snakebite-associated infections in the French departments of America

INTRODUCTION

Secondary infection is a frequent complication after bites by Bothrops atroxin French Guiana or B. lanceolatus in Martinique. Knowledge of the bacteria present in snake mouths is a valuable aid for determining probabilistic antibiotherapy after Bothrops bite. The objectives of this study were to describe the cultivable bacteria of the oral microbiota of the specimens of B. atrox and B. lanceolatus kept in captivity, and to study their susceptibility to antibiotics.

METHODS

Fifteen B. atrox and 15 B. lanceolatus were sampled. Bacterial cultures were performed and each morphotype on plates was identified using MALDI-TOF mass spectrometry. Antibiotic susceptibility was studied using the agar disk diffusion method, with possible determination of the MICs.

RESULTS

One hundred and twenty-two isolates were identified: 52 isolates and 13 species in B. atrox, 70 isolates and 23 species in B. lanceolatus. The main species were Providencia rettgeri, Morganella morganii, Pseudomonas aeruginosa, Staphylococcus xylosus, and Paeniclostridium sordellii (only in B. lanceolatus mouths). For B. atrox, 96% of isolates were susceptible to piperacillin/tazobactam, cefepime, imipenem and meropenem, 94% to ciprofloxacin and 76% to cefotaxime and ceftriaxone. For B. lanceolatus, 97% of isolates were susceptible to meropenem, 96% to cefepime, 93% to imipenem and piperacillin/tazobactam, 80% to ciprofloxacin, and 75% to cefotaxime and ceftriaxone. Many isolates were resistant towards amoxicillin/clavulanate.

CONCLUSION

Among currently recommended antibiotics, cefepime and piperacillin/tazobactam seem more suitable than cefotaxime or ceftriaxone in the event of a Bothrops bite. Ciprofloxacin may also be considered for B. atrox.

Clinical features and management of snake bites in 70 dogs in Korea

BACKGROUND

Snakebites remain a devastating and life-threatening environmental hazard. While the management of snakebites has been well described in humans, few clinical data and guidelines exist for dogs, especially in Korea.

OBJECTIVES

This retrospective study evaluated the clinical features of 70 dogs with snakebite wounds in Korea.

METHODS

The medical records of 72 dogs that presented to three animal hospitals from June 2008 to July 2021 were reviewed; among these, 70 dogs that met the inclusion criteria were enrolled. Their signalment, history, clinical signs, physical examination, blood analysis, treatment, and prognosis were also evaluated.

RESULTS

Of 70 dog owners, 35 (50%) witnessed the bite, with a mean time between bite and hospital presentation of 9.7 ± 4.1 h in 58 dogs. Blood smears were evaluated in 45 dogs, of which 28 (62%) showed echinocytosis. Anemia and acute kidney injury were found in 21 (29%) and 2 dogs (3%), respectively. A total of 37 dogs (53%) were hospitalized, 5 (7%) of which died.

CONCLUSIONS

The most significant finding was the high prevalence of echinocytosis. The data from this retrospective study could inform the management of dogs bitten by snakes in Korea.

Most adder bites in Finland's Lake District caused mild symptoms and severe poisoning was rare

AIM

This study investigated the incidence, clinical picture and treatment of paediatric adder bites in Finland's Lake District.

METHODS

Data were retrospectively collected on all children aged 0-15 years who were bitten by adders from 2006 to 2015 and treated at Tampere University Hospital. The severity was evaluated with the five-level Poisoning Severity Score.

RESULTS

We found that 109 children were treated following an adder bite, which was an incidence of 13 per 100,000 children from 0 to 15. Of these, 75 were under 8 years of age, with a median age of 3.5 years, and 34 were 8-15 years, with a median age of 10.3 years. The gender distribution was similar in both ages. Younger children were more likely to be bitten in their yards at home, whereas older children were more likely to be bitten in a forest. Older children reported more pain than younger patients. Most children were bitten on a lower limb, with minor symptoms such as localised redness and swelling, and received conservative treatment. Antivenom treatment was rarely administered and then only in severe cases or if symptoms progressed.

CONCLUSION

Adder bites mostly caused mild symptoms, severe poisoning was rare and antivenom was rarely given.

Septic Arthritis of the Proximal Interphalangeal Joint After Rattlesnake Bite

Snake bites are an uncommon injury requiring intervention by hand surgeons. While counteracting the effects of snake venom is the initial and urgent concern following a bite, infection caused by retention of a foreign body can present in a delayed fashion and may lead to increased morbidity. Standard radiographs of the injury should be carefully examined for foreign bodies, noting that retained snake teeth are somewhat radiolucent due to less mineralization as compared to bone and can be difficult to visualize. In our subject, a retained rattlesnake fang was found in association with a septic interphalangeal joint despite appropriate radiographic evaluation and thorough surgical irrigation and debridement upon initial presentation. This case report highlights a potential complication of snake bites, the importance of aggressive management, and the importance of increased suspicion for retained foreign bodies. Augmenting plain radiographs with additional imaging modalities, such as ultrasound, dark-field, and phase-contrast imaging, may aid in the diagnosis of retained foreign bodies after snake bites.

Bacteriological Investigation and Drug Resistance Analysis of Chronic Refractory Wound Secretions: A Clinical Study

BACKGROUND

Chronic refractory wounds were common and the treatments were complicated for burn and plastic surgeons. This study was to investigate the bacterial distribution characteristics and bacterial drug resistance of chronic refractory wound secretions.

METHODS

The authors retrospectively analyzed 425 patients with chronic refractory wound infection. The results of bacterial culture of wound secretions and drug sensitivity test were retrospectively analyzed. Further, the location area of the wound was divided into 4 regions, and the difference of the bacterial culture results between different regions was analyzed.

RESULTS

The wound secretions were cultured into 401 bacterial strains, including 206 gram-positive bacteria strains, accounting for 51.4%, with the highest detection rate of Staphylococcus aureus at 26.2% (105/401). There were 195 gram-negative bacteria strains, accounting for 48.6%, with the highest detection rate of Pseudomonas aeruginosa at 14.2% (57/401). There were 6 fungal strains. The proportion of gram-negative bacteria in the III region of the wound zone was significantly greater than that in the other 3 regions.

CONCLUSIONS

The detection rate of gram-positive bacteria and gram-negative bacteria of chronic refractory wound secretions is not much different. However, in the area close to the perineum (III region), gram-negative bacteria is significantly higher, which has a certain reference value for the use of antibiotics in clinical practice.Level of evidence: Level 4.

First reports of envenoming by South American water snakes Helicops angulatus and Hydrops triangularis from Bolivian Amazon: A one-year prospective study of non-front-fanged colubroid snakebites

Although snakebite incidence is underestimated in Bolivia, the Amazon region presents the highest incidence of these accidents. The local effects of bites by some non-front-fanged colubroid (NFFC) snakes are usually confused with that of viperids, resulting in the improper use of antivenoms and medications. Since there is scarce information on clinical treatment and management of NFFC bites from Bolivian Amazon, we conducted a prospective study of NFFC snakebites by reviewing the records of patients admitted with a snakebite diagnosis at Hospital Central Ivirgarzama, Bolivia. Snakebites were recorded for 12 months (December 2019-November 2020), including information about the sex and age of the patient, snakebite date, and treatment. Eight (5.7 %) of 152 patients were bitten by NFFC Helicops angulatus, Hydrops triangularis, and Erythrolamprus sp. Our results showed that 5/7 patients had prolonged clotting time and INR, as well as local edema and mild pain, suggesting systemic envenoming. Previously non-documented mild coagulopathy was observed for H. angulatus and H. triangularis bites. In some cases, incorrect first-aid measures, and inappropriate use of bothropic/lachesic antivenom were administrated. All the patients received supportive therapy and antihistamine drugs. Unsupported use of non-evidence-based treatments for snakebites such as corticoids, non-steroidal anti-inflammatory drugs (NSAIDs), and prophylactic antibiotic prescription were recorded. In conclusion, we describe the first formally documented snakebite cases produced by NFFC from Bolivia, highlighting the urgent need for training of the medical team in the snake identification, clinical management of snakebite, and the existence of a human-snake conflict involving NFFC species.

Simultaneous open fracture and rattlesnake bite on the same extremity

Open fractures and rattlesnake envenomations are two emergencies that each require emergent intervention and treatment. While each is common, when they occur simultaneously on the same extremity, it creates a syndrome that is quintessential Central Texas. We present the case of a 13-year-old boy who sustained a lower-extremity rattlesnake envenomation with concomitant open tibia and fibula fractures after being thrown from an all-terrain vehicle. The envenomation from the snake bite compelled us to first treat his developing coagulopathy with a delayed operative management of his fractures.

An investigation of conventional microbial culture for the Naja atra bite wound, and the comparison between culture-based 16S Sanger sequencing and 16S metagenomics of the snake oropharyngeal bacterial microbiota

Naja atra is a major venomous snake found in Taiwan. The bite of this snake causes extensive wound necrosis or necrotizing soft tissue infection. Conventional microbial culture-based techniques may fail to identify potential human pathogens and render antibiotics ineffective in the management of wound infection. Therefore, we evaluated 16S Sanger sequencing and next-generation sequencing (NGS) to identify bacterial species in the oropharynx of N. atra. Using conventional microbial culture methods and the VITEK 2 system, we isolated nine species from snakebite wounds. On the basis of the 16S Sanger sequencing of bacterial clones from agar plates, we identified 18 bacterial species in the oropharynx of N. atra, including Morganella morganii, Proteus vulgaris, and Proteus mirabilis, which were also present in the infected bite wound. Using NGS of 16S metagenomics, we uncovered more than 286 bacterial species in the oropharynx of N. atra. In addition, the bacterial species identified using 16S Sanger sequencing accounted for only 2% of those identified through NGS of 16S metagenomics. The bacterial microbiota of the oropharynx of N. atra were modeled better using NGS of 16S metagenomics compared to microbial culture-based techniques. Stenotrophomonas maltophilia, Acinetobacter baumannii, and Proteus penneri were also identified in the NGS of 16S metagenomics. Understanding the bacterial microbiota that are native to the oropharynx of N. atra, in addition to the bite wound, may have additional therapeutic implications regarding empiric antibiotic selection for managing N. atra bites.

Naja atra bites induce extensive wound necrotizing soft tissue infections in a substantial proportion of patients. Empiric antibiotic administration in snakebite patients is a common practice, but clinical reports indicate that this treatment was ineffective in preventing secondary infection given that the microbiota of the infected wound and oropharynx of the culprit snake were not properly established. In this study, only 9 species were detected in cobra bites using a conventional microbial culture method and the VITEK 2 system, whereas 18 species were detected in the cobra oropharynx using microbial culture-based 16S Sanger sequencing. Among these, Morganella morganii, Proteus vulgaris, and Proteus mirabilis were identified as common bacteria. Compared to microbial culture-based 16S Sanger sequencing, NGS-based 16S metagenomic sequencing detected more than 286 bacterial species. Stenotrophomonas maltophilia, Acinetobacter baumannii, and Proteus penneri only appeared with 16S metagenomic sequencing. These results suggest that NGS-based 16S metagenomic sequencing is a better tool for uncovering the bacterial microbiota of the N. atra oropharynx, which may help in developing a proper therapeutic strategy for patients with N. atra bites.

How Should Native Crotalid Envenomation Be Managed in the Emergency Department?

BACKGROUND

Pit vipers, also known as crotalids, are a group of snakes including rattlesnakes, copperheads, and cottonmouths (water moccasins). Crotalids have a broad geographic distribution across the United States, and bites from these snakes can carry significant morbidity. Their envenomations are characterized by local tissue effects, hematologic effects, and systemic effects. Envenomations are generally treated with 1 of 2 antivenoms available in the United States.

OBJECTIVE

We developed a series of clinical questions to assist and guide the emergency physician in the acute management of a patient envenomated by a crotalid.

METHODS

We conducted a PubMed literature review from January 1970 to May 2020 in English for articles with the keywords "bite" and "crotalidae."

RESULTS

Our literature search resulted in 177 articles. A total of 33 articles met criteria for rigorous review and citation in the development of these consensus guidelines.

CONCLUSIONS

Patients should be initially evaluated, stabilized, and assessed for local effects, hematologic effects, and systemic toxicity suggestive of envenomation. Antivenom should be given if toxic effects are present. Surgical intervention including debridement and fasciotomy should be avoided. Prophylactic antibiotics are not necessary.

Monocled Cobra (Naja kaouthia) Envenomations Requiring Mechanical Ventilation

BACKGROUND

Bites from nonnative snakes are uncommon, accounting for 1.1% of envenomations reported to poison centers between 2015 and 2018. Here we discuss two monocled cobra (Naja kaouthia) envenomations resulting in respiratory failure.

CASE REPORTS

A 30-year-old man and a 40-year-old man were bitten by their captive monocled cobras. At the first hospital, the first patient was mildly hypotensive, transiently bradycardic, and confused. He was intubated for respiratory distress. He was hypertensive to 211/119 mm Hg upon arrival to the second hospital. In the Emergency Department, cobra antivenom was administered. He was admitted to the medical intensive care unit (MICU) and had an additional bradycardic episode that corrected with atropine. He was extubated after 35 h. He was observed for an additional 9 h prior to going home, where he recovered without incident. The second patient developed abdominal pain, blurry vision, and dyspnea within 90 min of the bite. He was intubated at the first hospital. At the second hospital he received cobra antivenom and was admitted to the MICU. He was extubated after 9 h and discharged the following day with no further symptoms. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Envenomations after N. kaouthia bites are characterized by local tissue injury and various neurotoxic effects. Nonspecific signs and symptoms are common. Hematologic toxicity and cardiovascular manifestations are uncommon. Antivenom is the specific treatment for snake envenomation, but only certain antivenoms are indicated for N. kaouthia. Cholinesterase inhibitors may reduce toxicity from postsynaptic alpha toxins by increasing acetylcholine concentrations.

Antibiotic susceptibility of cultivable aerobic microbiota from the oral cavity of Echis carinatus from Odisha (India)

During a snake bite, the microbes may get transferred to the bite site and may cause secondary infection along with envenomation. The knowledge on the oral bacterial flora of snakes constitutes information important for snake bite management. The inadequately studied oral microflora of snakes differ geographically, temporally and among the members of the same species. The objective of this study is to determine the pattern of oral bacterial flora of Saw-scaled viper (Echis carinatus) and their susceptibility to antibiotics. Oral swabs were collected from nine healthy Saw-scaled vipers, subjected to microbiological, biochemical and molecular characterization. Additionally, these isolates were subjected to antimicrobial susceptibility testing using ICOSA-20-Plus and ICOSA-20-Minus. A wide range of pathogenic bacteria such as Salmonella arizonae, Pseudomonas stutzeri, Proteus penneri, Alcaligenes faecalis; Citrobacter diversus, C. freundii, Enterococcus faecalis, Bacillus anthracis, Staphylococcus sciuri and Achromobacter xylosoxidans were isolated as new additions to the floral diversity of saw scale viper. Most of the isolates were sensitive towards amikacin, azithromycin, imipenem, ciprofloxacin, gentamicin, ofloxacin, sparfloxacin, tobramycin, levofloxacin, kanamycin, tetracycline, and chloramphenicol while resistant to amoxyclav, cephalothin, cefpodoxime, Co-Trimoxazole, oxacillin and penicillin. The present study revealed that the bacterial flora of the oral cavity of Saw-scaled viper is resistant to many common antibiotics, which are often used for the treatment of snake-bite victims.

Incidence of snakebites in Can Tho Municipality, Mekong Delta, South Vietnam-Evaluation of the responsible snake species and treatment of snakebite envenoming

BACKGROUND

Data on incidence of snakebites and the responsible snake species are largely missing in Vietnam and comprehensive national guidelines for management of snakebite envenoming are not yet available. They are needed to estimate the scope of this health problem, to assess the demand for snake antivenom and to ensure the best possible treatment for snakebite victims.

METHODOLOGY/PRINCIPLE FINDINGS

A cross-sectional community-based survey was conducted from January to April 2018. Multistage cluster sampling was applied and snakebite incidence in Can Tho municipality, excluding two central districts of Can Tho city, was calculated at 48 (95%-confidence interval (CI): 20.5-99.8) snakebites per 100,000 person-years. Seven snakebite victims found during the survey reported 3 bites from green pit vipers and 4 bites from non-venomous snakes. In 2017 two treatment centres for snakebite envenoming in Can Tho city, the Military Hospital 121 and the Paediatric Hospital, received 520 admissions of snakebite victims. Two hundred sixty-seven came from Can Tho Municipality and 253 from neighbouring provinces. According to these data, the incidence of snakebites for Can Tho municipality was calculated at 21 (95%-CI: 18.5-23.7) snakebites per 100,000 person-years. Incidence was 14 (95%-CI: 12-17) snakebites per 100,000 person years in those 7 districts of the municipality which were part of the community survey. Green pit vipers were responsible for 92% of snakebite envenoming. Antivenom, antibiotics and corticosteroids were administered to 405 (90%), 379 (84%), and 310 (69%) out of 450 patients, respectively.

CONCLUSIONS

Incidence of snakebites in Can Tho Municipality is relatively low and green pit vipers are responsible for the vast majority of bites. Approximately one third of snakebite patients sought medical care in hospitals and although hospital data still underestimate the real incidence of snakebites, these statistics are valuable and can be obtained fast and inexpensively. Evaluation of patients' records indicates the need for development of guidelines for management of snakebite envenoming in Vietnam to ensure a rational use of antivenom and ancillary treatments.

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.

A case of envenomation by the false fer-de-lance snake Leptodeira annulata (Linnaeus, 1758) in the department of La Guajira, Colombia

Envenomations by colubrid snakes in Colombia are poorly known, consequently, the clinical relevance of these species in snakebite accidents has been historically underestimated. Herein, we report the first case of envenomation by opisthoglyphous snakes in Colombia occurred under fieldwork conditions at the municipality of Distracción, in the department of La Guajira. A female biologist was bitten on the index finger knuckle of her right hand when she tried to handle a false fer-de-lance snake (Leptodeira annulata). Ten minutes after the snakebite, the patient started to have symptoms of mild local envenomation such as edema, itching, and pain in the wound. After 40 minutes, the edema reached its maximum extension covering the dorsal surface of the right hand and causing complete loss of mobility. The clinical treatment focused on pain and swelling control. No laboratory tests were performed. The patient showed good progress with the total regression of the edema 120 hours after the snake-bite accident and complete recovery of the movement of the limb in one week. Venomous bites of "non-venomous snakes" (opisthoglyphous colubrid snakes) must be considered as a significant public health problem because patients lose their work capability during hours or even days and they are forced to seek medical assistance to treat the envenomation manifestations.

Caring for patients with venomous Crotalinae snakebites

Venomous snakebites are surprisingly common in the US. This article provides an overview of what to do when a patient has been bitten by a North American pit viper, a venomous subset of indigenous snakes.