Analysis of the clinical characteristics of warfarin-associated purple toe syndrome

Purple toe syndrome (PTS) represents a critical yet underrecognized complication of warfarin therapy. To characterize this condition, we conducted a retrospective analysis of all reported warfarin-associated PTS cases through April 30, 2025, without language restrictions. A total of 26 patients (17 male, 9 female) with a median age of 68 years were identified. Of these, 76.9% had pre-existing atherosclerotic disease and 66.7% showed elevated serum creatinine. Symptom onset occurred within three months of warfarin initiation in 53.9% of cases, with 84.0% exhibiting classic bilateral lower extremity involvement characterized by painful violaceous discoloration. Management strategies included warfarin discontinuation (88.5%), dose reduction (7.7%), renal replacement therapy (15.4%), LDL apheresis (11.5%), surgical or endovascular interventions (7.7%), and transition to alternative anticoagulant therapy. Notably, no cross-reactivity between anticoagulant classes was observed, and warfarin rechallenge was not categorically contraindicated in all cases. Outcomes were favorable in 69.2% of patients (symptom resolution), though 3.8% required amputation and 19.2% died within one year, suggesting this complication carries substantial morbidity despite therapeutic intervention. These finding suggest that warfarin-associated PTS warrants clinical awareness, particularly in elderly patients with pre-existing atherosclerotic disease and renal impairment. Early detection, warfarin cessation, and initiation of alternative anticoagulation appear important to help prevent irreversible outcomes.