METHODS: A 53-year-old woman of Cook Islands origin presented with exertional dyspnea, rapid atrial fibrillation, bilateral lower limb edema, and painful digital ischemia of her hallux. She was on warfarin therapy for atrial fibrillation and had a stable therapeutic international normalized ratio. Bilateral proximal lower limb deep vein thrombosis and digital gangrene subsequently developed in the setting of a supratherapeutic international normalized ratio and platelet count depletion. Her warfarin was reversed and heparin therapy was commenced with resulting correction of her thrombocytopenia.
CONCLUSIONS: We would like to attract the attention of the reader to the potential hazard of the use of warfarin in patients with malignancy. In our case, we also demonstrated a predictive value of supratherapeutic international normalized ratio and platelet count depletion that could herald massive thrombosis and gangrene in a patient who was previously stable on warfarin therapy. Early recognition and prompt reversal of warfarin in these circumstances is essential to correct the unbalanced prothrombotic process that leads to extensive thrombosis and gangrene. The outlook of such cases remains dismal and results in extensive morbidity and mortality.