Vipers of the Middle East: A Rich Source of Bioactive Molecules.

Snake venom serves as a tool of defense against threat and helps in prey digestion. It consists of a mixture of enzymes, such as phospholipase A2, metalloproteases, and l-amino acid oxidase, and toxins, including neurotoxins and cytotoxins. Beside their toxicity, venom components possess many pharmacological effects and have been used to design drugs and as biomarkers of diseases. Viperidae is one family of venomous snakes that is found nearly worldwide. However, three main vipers exist in the Middle Eastern region: Montivipera bornmuelleri, Macrovipera lebetina, and Vipera (Daboia) palaestinae. The venoms of these vipers have been the subject of many studies and are considered as a promising source of bioactive molecules. In this review, we present an overview of these three vipers, with a special focus on their venom composition as well as their biological activities, and we discuss further frameworks for the exploration of each venom.

Clinical Characteristics and Management of Snake Bite Injuries in the Jerusalem Area.

Venomous snake bites can constitute medical emergencies, and without immediate care may be life-threatening. This study describes the characteristics and management of patients suffering from snake bite injuries (SNIs) in the Jerusalem area. A retrospective analysis of all patients who were admitted to the Hadassah Medical Center emergency departments (EDs) due to SNIs between 1 January 2004 and 31 March 2018 was conducted. During this period, 104 patients were diagnosed with SNIs, of whom 32 (30.7%) were children. Overall, 74 (71.1%) patients were treated with antivenom, 43 (41.3%) were admitted to intensive care units, and 9 (8.6%) required treatment with vasopressors. No mortality was recorded. On ED admission, none of the adult patients presented with an altered mental state compared to 15.6% of the children (p < 0.00001). Cardiovascular symptoms were observed in 18.8% and 5.5% of the children and adults, respectively. Fang marks appeared in all of the children. These findings underscore the severity of SNIs and the differences in clinical presentation between children and adults in the Jerusalem region.

The Middle Eastern Cousin: Comparative Venomics of Daboia palaestinae and Daboia russelii.

Among the medically most important snakes in the world, the species belonging to the genus Daboia have been attributed to the highest number of human envenomings, deaths and disabilities. Given their significant clinical relevance, the venoms of Russell's vipers (D. russelii and D. siamensis) have been the primary focus of research. In contrast, the composition, activity, ecology and evolution of venom of its congener, the Palestine viper (D. palaestinae), have remained largely understudied. Therefore, to unravel the factors responsible for the enhanced medical relevance of D. russelii in comparison to D. palaestinae, we comparatively evaluated their venom proteomes, biochemical activities, and mortality and morbidity inflicting potentials. Furthermore, the synthesis and regulation of venom in snakes have also remained underinvestigated, and the relative contribution of each venom gland remains unclear. We address this knowledge gap by sequencing the tissue transcriptomes of both venom glands of D. palaestinae, and comparatively evaluating their contribution to the secreted venom concoction. Our findings highlight the disparity in the venom composition, function and toxicities of the two Daboia species. We also show that toxin production is not partitioned between the two venom glands of D. palaestinae.

Daboia (Vipera) palaestinae Envenomation in 123 Horses: Treatment and Efficacy of Antivenom Administration.

Envenomation by venomous snakes is life threatening for horses. However, the efficacy of available treatments for this occurrence, in horses, has not yet been adequately determined. The aim of this study was to describe the treatments provided in cases of Daboia palaestinae envenomation in horses and to evaluate the safety and efficacy of antivenom administration. Data regarding 123 equine snakebite cases were collected over four years from 25 veterinarians. The majority of horses were treated with procaine-penicillin (92.7%), non-steroidal anti-inflammatory drugs (82.3%), dexamethasone (81.4%), tetanus toxoid (91.1%) and antivenom (65.3%). The time interval between treatment and either cessation or 50% reduction of local swelling was linearly associated with case fatality (p < 0.001). The overall mortality rate was 20.3%. Treatment with procaine-penicillin was significantly associated with reduced mortality (OR = 0.11). Three horse-derived antivenom products were available during the study period, of which the horses were administered different brands of varying dosages. Administration of the recommended dosage of any of the aforementioned products led to a significant decrease in mortality (p = 0.014), even in severe cases (scoring 2 or greater on the equine snakebite severity scale). No adverse reactions were reported. The results of this study show that species-specific D. palaestinae antivenom administered at the manufacturer-recommended dosage is effective in significantly reducing mortality in cases of envenomation in horses.

Snakebites in Lebanon: A Descriptive Study of Snakebite Victims Treated at a Tertiary Care Center in Beirut, Lebanon.

BACKGROUND: Snakebites lead to at least 421,000 envenomations and result in more than 20,000 deaths per year worldwide. Few reports exist in the Mediterranean region. This study describes demographic and clinical characteristics, treatment modalities, and outcomes of snakebites in Lebanon. MATERIALS AND METHODS: This was a retrospective chart review of patients who presented with snakebite complaint to the emergency department between January 2000 and September 2014. RESULTS: A total of 24 patients were included in this study. The mean age was 34.6 (±16.4) years and 58.3% were males. Local manifestations were documented in 15 (62.5%) patients, systemic effects in 10 (41.7%), hematologic abnormalities in 10 (41.7%), and neurologic effects in 4 (16.7%) patients. Nine patients (37.5%) received antivenom. The median amount of antivenom administered was 40 ml or 4 vials (range: 1-8 vials). About 50% of patients were admitted to the hospital with 75% to an Intensive Care Unit and 25% to a regular bed. All were discharged home with a median hospital length of stay of 4 (interquartile range 11) days. Among those admitted, seven patients (58.3%) had at least one documented complication (compartment syndrome, fasciotomy, intubation, deep vein thrombosis, coagulopathy, acute respiratory distress syndrome, sepsis, congestive heart failure, cellulitis, upper gastrointestinal bleeding, and vaginal bleeding). CONCLUSION: Victims of snakebites in Lebanon developed local, systemic, hematologic, or neurologic manifestations. Complications from snakebites were frequent despite antivenom administration. Larger studies are needed to assess the efficacy of available antivenom and to possibly create a local antivenom for the treatment of snakebites in Lebanon.

Daboia (Vipera) palaestinae envenomation in horses: Clinical and hematological signs, risk factors for mortality and construction of a novel severity scoring system.

Daboia palaestinae is the most common venomous snake in Israel and an important cause of envenomations in humans and animals. Although specific antivenom is produced from horses, little documentation exists regarding the characteristics of envenomed horses. This survey was constructed to describe the clinical, hematological and biochemical characteristics of D. palaestinae envenomation in horses, to identify risk factors for fatality and to construct a prognostic snakebite severity scale (SSS) to be used by veterinarians in the field. Data regarding 123 equine snakebite cases were collected over four years. Clinical signs most frequently described were local swelling (100%), tachycardia (67%), increased respiratory effort (62%), bite marks (44%) and reduced appetite (50%). Blood samples were collected at initial presentation from 23 of these horses. Hematological and biochemical abnormalities described in the majority of the sampled cases included leukocytosis (52%), neutrophilia (78%), increased creatine phosphokinase (77%), hypoproteinemia (50%), decreased total carbon dioxide (54%), and hyperphosphatemia (54%). The overall case fatality rate was 20.3% (25/123 horses). Risk factors associated with increased mortality (P < 0.05) were body weight below 200 kg, hind limb envenomation, severity of local swelling, mental status, respiratory effort, bleeding disorders, dehydration, basophilia, monocytosis, bilirubinemia, hypocalcemia and hyperphosphatemia. These risk factors were used to construct an SSS adapted for the assessment of envenomed horses in the field, consisting of seven dichotomous parameters. A cutoff value of 1.5 predicted mortality with 95% sensitivity and 68% specificity. In the future, this tool could assist clinicians with case management and communication with owners.