Efficacy of specific antivenom and fresh frozen plasma in reversing Daboia palaestinae venom-induced hemostatic derangement

Atrial fibrillation caused by Daboia palestinae snakebite: a case report

Background

snake envenomation is a serious healthcare issue. Daboia palaestinae is an endemic species to the Middle East that is responsible for the majority of envenomation cases with serious health issue consequences.

Case Presentation

we report a case of a 20-year-old Palestinian man who presented to emergency room following a snake bite. He developed atrial fibrillation which is a rare but serious complication of D. palaestinae snakebite. We reviewed the proper approach and management to such cases.

Conclusion

cardiac arrhythmias are a rare but serious, often fatal, complication of snake envenomation. Early detection and proper management is key to avoid morbidity and mortality.

Persistent hypercoagulability in dogs envenomated by the European adder (Vipera berus berus)

Background

Envenomation by the European adder, Vipera berus berus (Vbb), is a medical emergency. The overall in vivo haemostatic effects of pro- and anticoagulant components in Vbb venom, and the downstream effects of cellular injury and systemic inflammation, are unclear.

Objectives

To longitudinally describe the global coagulation status of dogs after Vbb envenomation and compare to healthy controls. A secondary aim was to investigate differences between dogs treated with and without antivenom.

Methods

Citrated plasma was collected at presentation, 12 hours (h), 24 h, 36 h and 15 days after bite from 28 dogs envenomated by Vbb, and from 28 healthy controls at a single timepoint. Thrombin generation (initiated with and without exogenous phospholipids and tissue factor), thrombin-antithrombin (TAT)-complexes and the procoagulant activity of phosphatidylserine (PS)-expressing extracellular vesicles (EVs), expressed as PS-equivalents, were measured.

Results

At presentation the envenomated dogs were hypercoagulable compared to controls, measured as increased thrombin generation, TAT-complexes and PS-equivalents. The hypercoagulability decreased gradually but compared to controls thrombin generation and PS-equivalents were still increased at day 15. The discrepancy in peak thrombin between envenomated dogs and controls was greater when the measurement was phospholipid-dependent, indicating that PS-positive EVs contribute to hypercoagulability. Lag time was shorter in non-antivenom treated dogs, compared to antivenom treated dogs <24 h after envenomation.

Conclusions

Hypercoagulability was measured in dogs up to 15 days after Vbb envenomation. Dogs treated with antivenom may be less hypercoagulable than their non-antivenom treated counterparts. Thrombin generation is a promising diagnostic and monitoring tool for Vbb envenomation.