Relato de caso de intoxicación con superwarfarinas: un desafío terapéutico / Managing Superwarfarin Poisoning: A Challenging Case

La intoxicación humana por rodenticidas anticoagulantes de acción prolongada, conocidos como superwarfarinas, provoca coagulopatía de prolongado manejo. Presentamos el caso de un hombre de 42 años que ingirió una dosis tóxica de rodenticida en un intento suicida, evolucionando con epistaxis, INR de 11,6 y necesidad de hospitalización. Durante 7 días se realizaron controles seriados de pruebas de coagulación, con optimización de diferentes dosis de suplementación de Vitamina K. El caso destaca la potencia y vida media prolongada (aproximadamente 6 semanas) de este tipo de anticoagulantes, hecho que requiere un control clínico regular y una adherencia al tratamiento satisfactoria.

Human intoxication by long-acting anticoagulant rodenticides, known as superwarfarins, causes coagulopathy that is difficult to manage. We present the case of a 42-year-old man who ingested a toxic dose of rodenticide in a suicide attempt, evolving with epistaxis, INR of 11.6, and needing hospitalization. For seven days, serial controls of coagulation tests were carried out, with optimization of different doses of Vitamin K supplementation. The case highlights this type of anticoagulant's potency and prolonged half-life (approximately six weeks), which requires regular clinical control and satisfactory treatment adherence.

Evaluation of risk factors in patients with vitamin K-dependent coagulopathy presumed to be caused by exposure to brodifacoum

BACKGROUND/AIMS: Recently, many cases of vitamin K-dependent coagulopathy of unknown origin have been reported. Such patients lack any relevant family history and have no systemic disease, raising suspicion of superwarfarin intoxication. We evaluated individual risk factors causing coagulopathy and hemorrhagic symptoms in patients with suspected superwarfarin intoxication. In addition, we determined how to effectively treat vitamin K-dependent coagulopathy caused by suspected superwarfarin intoxication. METHODS: Seven patients with suspected superwarfarin intoxication who lacked any definitive history of rodenticide ingestion were included. Thirty-one patients initially diagnosed with rodenticide poisoning were also included. We performed a retrospective chart review of all subjects and examined clinical data including patient demographics and medical histories. RESULTS: Patients initially diagnosed with rodenticide poisoning were divided into two groups, one of which had a laboratory abnormality (prothrombin time [PT] > 13 seconds) and another group with PTs in the normal range. There was no significant difference between the two groups in any of age, gender, the extent of chronic alcohol consumption, the causative rodenticide, psychiatric problems, ingestion of drugs interacting with warfarin, the extent of intoxication, or the type of ingestion attempt. The albumin level of the former group was significantly lower than that of the latter group (p = 0.014). Furthermore, a significant difference between the two groups was evident in terms of simultaneous ingestion of rodenticide and alcohol (p = 0.023). CONCLUSIONS: Most patients with superwarfarin poisoning did not exhibit any complication. When such complications were evident, they were associated with serum albumin level and coingestion of rodenticide and alcohol.

Can we more efficiently save patients with vitamin K-dependent coagulopathy caused by superwarfarin intoxication?

No abstract available.

Korean Patients with Superwarfarin Intoxication and Their Outcome

This observational study aimed at evaluating recent superwarfarin intoxication of Korean patients. Ten patients were diagnosed as or highly suspicious for superwarfarin intoxication. Case report forms described by attending hematologists of the patients were collected and analyzed. Bleeding symptoms were varied among the patients. Patients uniformly showed prolonged prothrombin time (PT) and activated thromboplastin time (aPTT) with decreased activity of vitamin K dependent coagulation factors. Positive serum brodifacoum test results in 4 of 5 requested patients contributed to confirmatory diagnosis. Psychiatric interview revealed an attempted ingestion in one patient. High dose vitamin K1 therapy promptly corrected prolonged PT and aPTT, but hasty discontinuation caused repeated bleeding diathesis in 6 patients. Route of intoxication was unknown or not definite among 8 of 10 patients. Three patients had a possibility of environmental exposure considering their occupations: there might be intoxication by transdermal absorption or inhalation. Therefore, high dose and prolonged use of vitamin K1 therapy is necessary for effective detoxification. Further detailed investigation on environmental exposure and efforts to improve availability of the blood level test in clinic are requested.

Effect of supplementary feeding of vitamin K1 on difethialone treated Indian gerbil, Tatera indica Hardwicke in laboratory.

Two dosages (1 and 2 mg/kg) of vitamin K1 supplementation for 5 and 15 days were given to Indian gerbil T. indica fed on difethialone bait (0.0025%) for one day. The results indicated that the lower dosage could not reverse the anticoagulation process, however the period of mortality was considerably increased from 3-9 days (in control) to 5-14 days (5 days supplementation regime). Subsequently when the vitamin K1 dosage was doubled and given for 15 days, there was 100% reversal of anticoagulation process and all the test gerbils became normal within a month of poisoning with difethialone bait.