Interfang Distances of Rattlesnakes: Sexual, Interspecific, and Body Size-related Variation, and Implications for Snakebite Research and Management

Acute compartment syndrome and fasciotomy after a viper bite in Italy: a case report

BACKGROUND

Bites caused by European vipers are rare medical emergencies but can occasionally cause life-threatening complications. Viper venom causes local symptoms, which can be accompanied by systemic manifestations in severe cases. The local effects of snakebites include edema and, more rarely, necrosis and compartment syndrome. The consequences of envenomation are often more pronounced in children due to their smaller body size.

CASE PRESENTATION

We present the case of a 6-year-old girl who experienced multiple viper bites in the lower limb in northwest Italy. The girl received supportive care but progressed to develop compartment syndrome that required emergency fasciotomy. The patient's condition improved promptly after surgical decompression and administration of antivenom, but full recovery required prolonged hospitalization and rehabilitation.

CONCLUSIONS

This case highlights the importance of obtaining a timely assessment of the severity of viper envenomation without delaying the administration of antivenom in most serious cases. The presence of multiple bite marks on the patient is one factor that may help to predict the clinical severity of snakebites and anticipate symptom progression.

Considerations for the development of a field-based medical device for the administration of adjunctive therapies for snakebite envenoming

The timely administration of antivenom is the most effective method currently available to reduce the burden of snakebite envenoming (SBE), a neglected tropical disease that most often affects rural agricultural global populations. There is increasing interest in the development of adjunctive small molecule and biologic therapeutics that target the most problematic venom components to bridge the time-gap between initial SBE and the administration antivenom. Unique combinations of these therapeutics could provide relief from the toxic effects of regional groupings of medically relevant snake species. The application a PRISMA/PICO literature search methodology demonstrated an increasing interest in the rapid administration of therapies to improve patient symptoms and outcomes after SBE. Advice from expert interviews and considerations regarding the potential routes of therapy administration, anatomical bite location, and species-specific venom delivery have provided a framework to identify ideal metrics and potential hurdles for the development of a field-based medical device that could be used immediately after SBE to deliver adjunctive therapies. The use of subcutaneous (SC) or intramuscular (IM) injection were identified as potential routes of administration of both small molecule and biologic therapies. The development of a field-based medical device for the delivery of adjunctive SBE therapies presents unique challenges that will require a collaborative and transdisciplinary approach to be successful.

Snakebite Envenoming a Challenging Diagnosis for the Forensic Pathologist: A Systematic Review

Snakebite envenoming (SBE) is a public health issue in developing countries. The estimated annual global incidence of snakebites is about 5.4 million snakebites per year, resulting from 1.8 to 2.7 million cases of SBE and from 81,000 to 138,000 deaths with 400,000 survivors suffering permanent physical and psychological disabilities. There are more than 3000 species of snakes around the world: 600 are venomous and over 200 are considered to be medically important because of their clinical effects. The severity of SBE depends on several factors among which bite localization, snake's size, condition of glands and teeth, bite angle and bite duration, the microflora of the snake's mouth and victim's skin, age of the victim, weight, health status, and victim's activity after a bite. Snake venoms are mixtures of protein families, and each of these families contains many different toxins or toxin isoforms. Based on their effects, snake venoms can be classified as hemotoxic, neurotoxic, or cytotoxic and they can all act together involving multiple tissues and organs. When the bite is fatal, the mechanism of death is primarily related to the paralysis of respiratory muscles, which causes asphyxia and hypoxic-ischemic encephalopathy, but also anaphylactic shock, hemorrhagic shock, cardiomyopathy, acute tubular necrosis (ATN). The purpose of this literature review is to evaluate epidemiological and post-mortem examination findings in fatal SBEs in order to better understand the pathophysiological mechanisms, thus helping pathologists in defining the correct diagnosis.

Relationship between snake size and clinical, epidemiological and laboratory aspects of Bothrops atrox snakebites in the Western Brazilian Amazon

In the Brazilian Amazon, snakebites are a significant problem, especially for populations in rural areas, particularly in forests, where victims are a considerable distance from hospital care. Several factors are associated with the severity of the accident, such as the size and age of the snake. This study aims to compare the clinical, epidemiological and laboratory aspects of envenomation to the size of Bothrops atrox snakes. Clinical, epidemiological and laboratory variables were collected from patients bitten by B. atrox and who were admitted to a hospital in the city of Cruzeiro do Sul (western Brazilian Amazon). When the two punctures of the teeth were present in the bite sign, the distance between these was measured. When taken to the hospital, the snake was measured; otherwise, its size was estimated via interviews with patients. In 92 cases, the size of the snake was estimated, and most of these were caused by small snakes. Bites of small snakes occur mainly on the feet, while larger specimens reach the legs or higher regions. Small snakes were associated primarily with mild and moderate snakebites, with more presence of hemorrhagic manifestations, while larger snakes were responsible for severe cases and characterized by local effects (necrosis, edema, flictena, compartment syndrome, and infection) and patients were treated with a higher amount of antivenom and for a longer period of hospitalization. The distance of the punctures was related to the size of the snake and the severity of the local envenomation. The observation of the distance between puncture marks when present, which is correlated with the length of the specimen, as well as the estimation of the snake size by the patient, may provide more support for the health professional on the prognosis of envenomation. The use of boots in activities in rural areas and forests could contribute to a lower rate of cases of snakebites, and health education on preventive measures and first aid for populations is fundamental.