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The clinical evolution and management of a 22-yr-old male envenomed by a captive female inland taipan, Oxyuranus microlepidotus (McCoy, 1879), Elapidae, at a public educational reptile exhibit (Florida, USA) is reported. The patient was bitten (quick 'bite and release') in the right hand between digits #3 and 4 while performing captive maintenance. The victim did not attempt any first aid, but urgently presented to the local hospital within 25 mins post-bite. The patient had an unremarkable medical/surgical history including no previous envenoming/treatment with antivenom. Within approximately 5 mins post-bite he reported experiencing transient loss of consciousness/syncope, altered sensorium, nausea, dull headache, weakness, and "severe" bite site pain. Laboratory investigations revealed profound defibrinating coagulopathy including thrombocytopenia; there was only mildly elevated creatine kinase and renal function remained within normal limits. The patient's clinical evolution included cranial nerve palsies manifested as dysconjugate gaze, persistent, but minor, bite site bleeding, asthenia and reported myalgia as well as prolonged intense bite site pain. He was successfully and uneventfully treated with four vials of Australian polyvalent antivenom and one vial of taipan monovalent; all were expired products with expiration dates ranging from one month to 38 years. Effective antivenom therapy might have been achieved with only 2, possibly 3 vials; however, concerns about reduced efficacy of the long-expired antivenom (4/5 vials were expired 18-38 years) and persistent bite site bleeding/pain contributed to the provision of the additional vials. The patient recovered sufficiently for discharge in 48 h; there were no sequelae. There have been approximately 12 formally documented cases of O. microlepidotus envenoming and selected, detailed examples of these are briefly considered and compared with the clinical evolution of our patient; patient-centred recommendations for management of Oxyuranus spp. envenoming are discussed. The need for advanced preparedness and an action plan for any institution/collection that contains non-native, medically significant venomous species is emphasised, and a general recommended approach is outlined., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Snakebite is a relatively common health condition in Iran with a diverse snake fauna, especially in tropical southern and mountainous western areas of the country with a plethora of snake species. The list of medically important snakes, circumstances and effects of their bite, and necessary medical care require critical appraisal and should be updated regularly. This study aims to review and map the distributions of medically important snake species of Iran, re-evaluate their taxonomy, review their venomics, describe the clinical effects of envenoming, and discuss medical management and treatment, including the use of antivenom. Nearly 350 published articles and 26 textbooks with information on venomous and mildly venomous snake species and snakebites of Iran, were reviewed, many in Persian (Farsi) language, making them relatively inaccessible to an international readership. This has resulted in a revised updated list of Iran's medically important snake species, with taxonomic revisions of some, compilation of their morphological features, remapping of their geographical distributions, and description of species-specific clinical effects of envenoming. Moreover, the antivenom manufactured in Iran is discussed, together with treatment protocols that have been developed for the hospital management of envenomed patients., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Non-front-fanged colubroid snakes (NFFC; formerly and artificially taxonomically assembled as "colubrids") comprise about 70% of extant snake species and include several taxa now known to cause lethal or life threatening envenoming in humans. Although the medical risks of bites by only a handful of species have been documented, a growing number of NFFC are implicated in medically significant bites. The majority of these snakes have oral products (Duvernoy's secretions, or venoms) with unknown biomedical properties and their potential for causing harm in humans is unknown. Increasingly, multiple NFFC species are entering the commercial snake trade posing an uncertain risk. Published case reports describing NFFC bites were assessed for evidence-based value, clinical detail and verified species identification. These data were subjected to meta-analysis and a hazard index was generated for select taxa. Cases on which we consulted or personally treated were included and subjected to the same assessment criteria. Cases involving approximately 120 species met the selection criteria, and a small subset designated Hazard Level 1 (most hazardous), contained 5 species with lethal potential. Recommended management of these cases included antivenom for 3 species, Dispholidus typus, Rhabdophis tiginis, Rhabdophis subminiatus, whereas others in this subset without commercially available antivenoms (Thelotornis spp.) were treated with plasma/erythrocyte replacement therapy and supportive care. Heparin, antifibrinolytics and/or plasmapheresis/exchange transfusion have been used in the management of some Hazard Level 1 envenomings, but evidence-based analysis positively contraindicates the use of any of these interventions. Hazard Level 2/3 species were involved in cases containing mixed quality data that implicated these taxa (e.g. Boiga irregularis, Philodryas olfersii, Malpolon monspessulanus) with bites that caused rare systemic effects. Recommended management may include use of acetylcholinesterase inhibitors (e.g. neostigmine) and wound care on a case-by-case basis. Hazard level 3 species comprised a larger group capable of producing significant local effects only, often associated with a protracted bite (eg Heterodon nasicus, Borikenophis (Alsophis) portoricensis, Platyceps (Coluber) rhodorachis). Management is restricted to wound care. Bites by Hazard level 4 species comprised the majority of surveyed taxa and these showed only minor effects of no clinical importance. This study has produced a comprehensive evidence-based listing of NFFC snakes tabulated against medical significance of bites, together with best-practice management recommendations. This analysis assumes increasing importance, as there is growing exposure to lesser-known NFFC snakes, particularly in captive collections that may uncover further species of significance in the future. Careful and accurate documentation of bites by verified species of NFFC snakes is required to increase the evidence base and establish the best medical management approach for each species., (Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.)

A case of clinically significant local envenoming resulting from a bite inflicted by a Western hognose snake, Heterodon nasicus, is described. The patient was bitten while offering a juvenile mouse to a captive snake. The snake maintained a grip on the patient's arm (left anticubital fossa) for several minutes. The bite resulted in marked edema, ecchymoses, lymphadenopathy, cutaneous signs suggestive of mild cellulitis and blister formation. There were no systemic effects. Recovery was complete after approximately five months. Several documented Heterodon sp. bites with significant clinical effects are reviewed. This common xenodontine colubrid must be considered capable of inflicting medically significant bites. It is currently unclear whether the pathological changes associated with these bites are due to specific Duvernoy's secretion components, Type I hypersensitivity or a combination of these. The influence of the feeding response on the severity of clinical effects is considered as is the discrepancy between experimentally verified pharmacological activities of Duvernoy's secretions from Heterodon sp. and medical sequelae of documented bites. Although hognose snakes may uncommonly produce medically significant bites, they should not be considered dangerous or venomous. Captive specimens should be handled carefully, particularly when offered food.

This case report represents a documentation of severe envenomation by Proatheris superciliaris, a species for which no specific antivenom exists. A 27-year-old male bitten on the finger by an adult P. superciliaris developed immediate severe pain radiating up the limb and local ecchymotic features with tissue necrosis ensuing over the following 36h, requiring debridement of necrotic tissue. Approximately 72h post-envenomation jaundice and hemoglobinuria were observed, but no other clinical signs of coagulopathy or hemorrhage. Hemolysis was evidenced by fragmented red blood cells and hyperbilirubinemia. Declining renal function ensued. Hematology revealed a reduction in reticulocyte count, schistocytosis, and a marked thrombocytopenia. The coagulation profile showed partial thromboplastin time and fibrinogen values within normal range and slight prothrombin time elevation. Thrombotic microangiopathy similar to hemolytic uremic syndrome developed, and daily plasmapheresis was initiated on day 4. Erythropoietin therapy was started on the 9th day. Gradual resolution of acute systemic complications followed over a 3-month period. The debrided bite site healed and the fingernail-beds demonstrated the return of normal capillary refill. Neurotoxic effects of venom were not observed.