Superwarfarin poisoning

Area of Science:

• Toxicology
• Public Health
• Internal Medicine

Background:

• Superwarfarin sodium exposure and poisoning represent an increasing public health issue, with reported cases rising significantly between 1988 and 1995.
• Cases of superwarfarin poisoning can stem from accidental exposure, suicide attempts, or Munchausen syndrome, presenting diagnostic challenges.

Purpose of the Study:

• To investigate the causes, clinical presentations, diagnostic difficulties, treatment strategies, and prevention of superwarfarin poisoning.
• To analyze cases of superwarfarin exposure in a tertiary referral center in rural Wisconsin.

Main Methods:

• Retrospective review of eleven patient cases meeting criteria for superwarfarin exposure or poisoning.
• Examination of clinical manifestations, diagnostic timelines, treatment interventions, and patient outcomes.

Main Results:

• Eleven cases were identified: 7 accidental pediatric ingestions, 2 adult Munchausen syndrome cases, and 2 suicide attempts (1 teenager, 1 adult).
• Brodifacoum was the agent in nine cases. Accidental ingestions and suicide attempts were diagnosed promptly, unlike Munchausen syndrome cases which had delayed diagnoses.
• Anticoagulation reversal was rapid in accidental and suicide cases, but prolonged for Munchausen syndrome patients. No fatalities occurred.

Conclusions:

• Superwarfarin poisoning should be considered in patients with vitamin K deficiency-like coagulopathy unresponsive to standard vitamin K1 therapy, excluding other common causes.
• The increasing incidence of superwarfarin poisoning necessitates its inclusion in differential diagnoses for unexplained coagulopathies.