Toxicon : official journal of the International Society on Toxinology
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Randomized Controlled Trial Comparative Study
Subacute coagulopathy in a randomized, comparative trial of Fab and F(ab')2 antivenoms.
Envenomation by pit vipers is associated with coagulation disorders including hypofibrinogenemia and thrombocytopenia. These abnormalities correct following antivenom treatment during the acute phase of the disease. Delayed or recurrent coagulation abnormalities have been reported following use of Fab antivenom, resulting in risk of hemorrhage or death. ⋯ Following the acute phase of presentation and treatment for pit viper envenomation, there appears to be a roughly 2-week subacute phase of the disease during which ongoing presence of venom may result in serious delayed or recurrent coagulation defects. Late hypofibrinogenemia and thrombocytopenia are associated with recurrent venonemia and drop in antivenom levels. This pattern was apparent in patients treated with Fab antivenom but was not seen among F(ab')2 recipients in this Phase 2 study, consistent with pharmacokinetic differences between the two products. Improved understanding of Fab pharmacokinetics is important for the management of coagulopathy-prone pit viper envenomation. Use of F(ab')2 antivenom may prevent recurrent venom effects, but larger studies are necessary for statistical confirmation of this observation.
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Scorpion envenomation is a poorly explored problem in French Guiana. The aim of our study was to describe the epidemiological and clinical features of scorpion stings. ⋯ Scorpion envenomation is an increasing accident in French Guiana. Symptoms vary from mild to severe and can require ICU admission. Practitioners have to be made aware of severe cases found mainly in children.
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Rattlesnake bites in horses are not uncommon and the clinical outcomes are widely variable. Treatment of horses with anti-venom is often cost prohibitive and could have negative consequences; therefore, the development of a quantitative test to determine if anti-venom therapy is indicated would be valuable. The objective of this study was to develop an ELISA to detect rattlesnake venom in biological samples from clinically bitten horses. ⋯ For this, first peak venom concentration needs to be determined. More frequent, consistent sample collection will be required to define a venom elimination pattern in horses and determine the ideal sample collection time to best estimate the maximum venom dose. This report describes development of an assay with the ability to detect rattlesnake venom in the urine and at the bite site of horses with a clinical diagnosis of rattlesnake bite.
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The transient receptor potential vanilloid 1(TRPV1) channels are members of the transient receptor potential (TRP) superfamily. Members of this family are expressed in primary sensory neurons and are best known for their role in nociception and sensory transmission. Multiple painful stimuli can activate these channels. ⋯ For example, BoNT/A decreases TRPV1 expression levels by blocking TRPV1 trafficking to the plasma membrane, although the exact mechanism is still under debate. Vanillotoxins from tarantula (Psalmopoeus cambridgei) are proposed to activate TRPV1 via interaction with a region of TRPV1 that is homologous to voltage-dependent ion channels. Here, we offer a description of the present state of knowledge for this complex subject.
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Chronic pain indicates a type of pain that lasts over time and is accompanied by diagnostic and therapeutic difficulties. It follows that treatment failures are common and patients roam from doctor to doctor in search of an effective care program. So there is an urgent need for long-acting and effective therapeutics to alleviate symptoms of the varied forms of chronic pain. ⋯ Its analgesic effect has been used in clinical practice with satisfactory results. This review provides an introduction of a hypothesis for the mechanism by which BoNT/A eases chronic pain. It also summarizes the clinical therapeutic effects of BoNT/A in different types of chronic pain and its potential prospects.