Differential Diagnosis for Purple Soles of Feet with Factor 5

• Single Most Likely Diagnosis
  • Warfarin-induced skin necrosis: This condition is a strong candidate given the mention of "factor 5," which likely refers to Factor V Leiden, a clotting disorder. Warfarin, an anticoagulant, can paradoxically cause skin necrosis, especially in individuals with underlying clotting disorders. The purple soles could be indicative of necrotic tissue.
• Other Likely Diagnoses
  • Disseminated intravascular coagulation (DIC): This is a condition characterized by widespread clotting in small blood vessels, which can lead to organ failure. It could cause purple discoloration due to bleeding under the skin.
  • Antiphospholipid syndrome: This autoimmune disorder can cause blood clots in arteries and veins, potentially leading to skin manifestations like purple soles.
  • Vasculitis: Inflammation of blood vessels can cause a variety of skin symptoms, including purpura (purple spots).
• Do Not Miss Diagnoses
  • Sepsis: Although less directly related to the specific symptoms, sepsis can cause a wide range of skin manifestations, including purpura, and is a life-threatening condition that must not be missed.
  • Meningococcemia: This bacterial infection can cause purpura fulminans, a condition characterized by rapid progression of hemorrhagic necrosis of the skin, which could present with purple soles.
• Rare Diagnoses
  • Cholesterol crystal embolization: This condition occurs when cholesterol crystals break off from plaques in the arteries and travel to smaller vessels, causing blockages. It can lead to skin discoloration, including purple soles, but is relatively rare.
  • Calciphylaxis: A rare condition seen in patients with end-stage renal disease, characterized by calcification of small blood vessels, which can lead to skin necrosis and could potentially cause purple soles.