Superwarfarin Exposure: An Important Uncommon Cause of Painless Bleeding

Abstract

Painless bleeding in a patient presenting from the community with elevated coagulation studies rarely makes the physicians suspect superwarfarin or rodenticide poisoning. Although a significant number of superwarfarin exposure cases are diagnosed every year, we believe there appears to be delay in diagnosis and confusion in determining what is the ideal way to treat and monitor these patients during the management. This is the first thorough literature review of all the reported cases of superwarfarin poisoning which also studied the clinical presentation, management and follow-up patterns. We present a 70-year-old man who presented to the emergency room with epistaxis, melena, colacolored urine with elevated prothrombin time (PT), activated partial thromboplastin time (aPTT) and international normalized ratio (INR). Mixing studies showed complete correction of coagulopathy indicative of factor deficiency. Additional history revealed that the patient had arguments with family member at home and made us suspect superwarfarin exposure. Qualitative brodifacoum testing was positive and was managed with fresh frozen plasma and high doses of vitamin K1 (phytomenadione) with serial monitoring of INR and clinical symptoms. Superwarfarin poisoning should be considered in the differential diagnosis of a patient who presents with above clinical and laboratory profile especially in the absence of any history of coagulopathy or anticoagulant use. We want to raise public and especially physician awareness that history taking, early diagnosis and managing in right clinical setting play a significant role in survival of these patients.

Rodenticide poisoning leading to cerebral hemorrhage: A case report

“…Some of the clinical manifestations of AR poisoning include systemic mucosal and organ bleeding, common hematuria, skin ecchymosis, gingival bleeding, gastrointestinal bleeding, epistaxis, and hemoptysis. [ 10 , 11 ] ARs inhibit the production of vitamin K by inhibiting the activity of vitamin K 2, 3-epoxide reductase. In addition, the glutamic acid residues of vitamin K-dependent coagulins cannot be carboxylated, thus affecting the activation of coagulation factor II, VII, IX, and X, making them unable to exert their coagulant activity.…”

Intoksikasi Superwarfarin dengan Ensefalopati Toksik dan Gagal Ginjal Akut pada Anak : sebuah laporan kasus

“…Namun, superwarfarin memiliki efek jangka panjang yang lebih kuat dan tahan lama daripada warfarin standar, sehingga penggunaannya harus sangat hati-hati dan terkontrol. (Kodali et al, 2019) Kasus intoksikasi superwarfarin masih relatif jarang dilaporkan, dan mayoritas laporan kasus yang ada berasal dari wilayah tertentu. Intoksikasi superwarfarin dapat terjadi akibat penggunaan yang salah atau penyalahgunaan zat ini, yang dapat mengakibatkan dampak kesehatan serius.…”

Retrospective analysis of clinical characteristics of and treatment strategies for patients with long‐acting anticoagulant rodenticide poisoning

“…3 The mechanism of LAAR involves the inhibition of vitamin K epoxide reductase (VKOR) to disrupt the vitamin K cycle, resulting in the undercarboxylation of vitamin K-dependent proteins and the reduced production of vitamin K-dependent coagulation factors II, VII, IX and X. [1][2][3]5,[11][12][13] In humans, the main route of exposure is oral, with fewer poisonings through the skin or respiratory routes. 2 LAARs are more potent than warfarin (half-life of warfarin is 10-16 h in animals and 40-46 h in humans), have a longer half-life and act faster.…”