Differential Diagnosis for Foot Rubor

• Single most likely diagnosis
  • Erythromelalgia: This condition is characterized by burning pain, heat, and redness in the hands and feet, which matches the symptom of foot rubor. It can be primary or secondary to other conditions like myeloproliferative disorders.
• Other Likely diagnoses
  • Cellulitis: A bacterial skin infection that can cause redness, swelling, and warmth, which could be mistaken for rubor. It's a common condition that requires prompt antibiotic treatment.
  • Deep Vein Thrombosis (DVT): While DVT typically presents with swelling and pain, in some cases, it can cause redness and warmth in the affected limb, mimicking foot rubor.
  • Gout: An inflammatory arthritis that can cause redness, swelling, and pain in the joints of the foot, potentially leading to a presentation similar to foot rubor.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Necrotizing Fasciitis: A severe bacterial infection that can cause redness, swelling, and pain in the skin and soft tissues. It's a medical emergency that requires immediate surgical intervention.
  • Septic Arthritis: A bacterial infection within a joint, which can present with redness, swelling, and pain. Prompt antibiotic treatment is essential to prevent joint destruction.
  • Compartment Syndrome: A condition where increased pressure within a muscle compartment can lead to nerve and muscle damage. It can present with pain, swelling, and redness, and requires urgent medical attention.
• Rare diagnoses
  • Complex Regional Pain Syndrome (CRPS): A chronic pain condition that can cause changes in skin temperature and color, including redness, in the affected limb.
  • Lymphedema: A condition characterized by chronic swelling due to impaired lymphatic drainage, which can sometimes present with redness and warmth.
  • Kaposi's Sarcoma: A rare cancer that can cause red or purple lesions on the skin, including the feet, especially in immunocompromised individuals.