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The Komodo dragon (Varanus komodoensis) is the world's largest living lizard and exists in private captivity worldwide. Bites to humans are rare and have been proposed to be both infectious and venomous. A 43-year-old zookeeper was bitten on the leg by a Komodo dragon and suffered local tissue damage with no excessive bleeding or systemic symptoms to suggest envenomation. No specific therapy was administered other than local wound irrigation. The patient was placed on prophylactic antibiotics and on follow-up, which revealed no local or systemic infections, and no other systemic complaints. Although venomous lizard bites are uncommon, prompt recognition of possible envenomation and management of these bites is important. Komodo dragon bites may produce not only superficial lacerations but also deep tissue injury, but are unlikely to produce serious systemic effects; whereas Gila monster and beaded lizard bites may cause delayed angioedema, hypotension, and other systemic symptoms. Treatment in all cases is supportive. [ABSTRACT FROM AUTHOR]

There are two Food and Drug Administration (FDA)-approved antivenoms available for rattlesnake envenomations in the United States: the equine-derived F (ab')2 product sold with the brand name Anavip (F (ab')2 AV) and the ovine-derived Fab product sold with the brand name Crofab (FabAV). To compare the clinical outcomes of rattlesnake envenomation patients treated either with FabAV or F (ab')2AV or a combination of these. This is a retrospective chart review of all human rattlesnake envenomations requiring antivenom reported to one regional poison control center in 2019. Patients were categorized as receiving F (ab')2 AV, FabAV, or a combination of both. Baseline characteristics included demographics, time between envenomation and administering antivenom, an abbreviated snakebite severity score (ASSS), and the presence of coagulopathy at presentation. There were a total of 123 patients requiring antivenom. Of these, 57 (46.3%) received FabAV, 53 (43.1%) received F (ab')2 AV, and 13 (10.6%) received a combination of these. Those receiving F (ab')2 AV were younger, with an average age of 40.8 (±25.0) years versus 51.3 (±19.9) years (p = 0.0161) for those receiving FabAV. Time between envenomation and antivenom administration, ASSS, and the percentage of those with coagulopathy at presentation were otherwise similar. Patients treated with F (ab')2 AV or FabAV received a similar total number of vials [16.0 vials (±6.1) vs 14.5 vials (±5.4), p = 0.189], but patients treated with F (ab')2 AV were more frequently given additional doses [31 patients (58.5%) vs. 22 FabAV patients (38.6%), p = 0.0051]. In patients with outpatient follow-up for 2 weeks, fewer patients treated with F (ab')2 AV developed late coagulopathy [5 patients (11.1%) vs 22 FabAV patients (48.9%), p = 0.0004]. Adverse events were generally mild and uncommon with no difference in frequency between patients who received either antivenom (2 F (ab')2 AV patients vs 4 FabAV patients, p = 0.6637). Other than patient age, we found no significant difference in the baseline demographics, time between envenomation and administering antivenom, an abbreviated snakebite severity score (ASSS), and the presence of coagulopathy at presentation between patients receiving F (ab')2 AV or FabAV. Patients receiving F (ab')2 AV were more likely to be given an additional dose beyond the minimum typical treatment course, but less likely to develop late coagulopathy. Adverse events were uncommon and generally mild whether patients received either antivenom. [Display omitted] • A comparison of Fab and an F (ab')2 rattlesnake antivenom in the United States. • Patients treated with either antivenom received a similar total number of vials. • Fewer patients treated with F (ab')2 antivenom developed late coagulopathy. • Adverse events were generally mild and uncommon with both antivenoms. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]