Differential Diagnosis for Bilateral Swelling in Feet and Legs with a Prominent Vein

• Single most likely diagnosis:

  • Varicose Veins: The description of a big vein bulging at the front of the leg, in the context of bilateral swelling in feet and legs, especially in an elderly patient, points towards varicose veins. This condition is common in older adults due to weakened vein walls and valves. The fact that the legs are soft, non-tender, and not hot, with the patient feeling well, further supports this diagnosis as varicose veins can be asymptomatic aside from their cosmetic appearance and occasional discomfort.

• Other Likely diagnoses:

  • Chronic Venous Insufficiency (CVI): This condition can lead to swelling, skin changes, and prominent veins due to the veins' inability to send blood back to the heart properly. It's a common cause of leg swelling and could explain the bulging vein.
  • Lymphedema: Although less likely given the description of the bulging vein, lymphedema could cause swelling in the legs. However, it typically presents with a more significant difference in limb size and may not directly explain the prominent vein.
  • Dependent Edema: This is a common condition in elderly or less mobile individuals where fluid accumulates in the legs due to gravity. While it could explain the swelling, it doesn't directly account for the prominent vein.

• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.):

  • Deep Vein Thrombosis (DVT): Although the legs are described as soft and non-tender, DVT can sometimes present without significant pain or warmth. The presence of a bulging vein could potentially be a sign of a large clot, making this a critical diagnosis not to miss due to its risk of leading to pulmonary embolism.
  • Cellulitis or Infection: While the legs are described as not being hot or tender, early stages of infection might not always present with these classic signs, especially in elderly patients whose immune response might be blunted.

• Rare diagnoses:

  • Klippel-Trenaunay Syndrome: A rare congenital condition characterized by port-wine stains, varicose veins, and bony and soft tissue hypertrophy. It could explain the prominent vein but would typically be identified earlier in life.
  • Parkes Weber Syndrome: Similar to Klippel-Trenaunay, this is a rare condition involving congenital malformations of blood vessels, which could lead to prominent veins and swelling. However, it's exceedingly rare and usually diagnosed in younger patients.