Differential Diagnosis for Bilateral Swelling with Unilateral Bulge on Left Leg and Recent Upper Forearm DVT

• Single Most Likely Diagnosis
  • Post-thrombotic syndrome (PTS) with possible recurrent DVT: This condition is a likely consequence of a recent DVT, especially given the history of an upper forearm DVT. The unilateral bulge could be indicative of a venous ulcer or significant edema due to chronic venous insufficiency.
• Other Likely Diagnoses
  • Cellulitis: Given the soft, tender swelling, cellulitis is a plausible diagnosis, especially if there's an infectious component. However, the recent history of DVT complicates this picture.
  • Lymphedema: This could be a secondary condition following the DVT, especially if there was significant damage to the lymphatic vessels during the thrombotic event or its treatment.
  • Venous insufficiency: Chronic venous insufficiency could lead to bilateral swelling, with the unilateral bulge being a sign of more severe disease on the left side.
• Do Not Miss Diagnoses
  • Pulmonary embolism (PE): Although the symptoms are localized to the legs, a recent DVT increases the risk of PE, which is life-threatening and requires immediate attention.
  • Phlegmasia cerulea dolens: A severe form of DVT that can lead to significant swelling, pain, and potentially gangrene. It's a medical emergency.
  • Compartment syndrome: Especially if the swelling is accompanied by significant pain, pallor, poikilothermia, paresthesia, and pulselessness, compartment syndrome must be considered and ruled out promptly.
• Rare Diagnoses
  • Lipedema: A chronic condition characterized by the symmetric enlargement of the legs due to deposits of fat in the subcutaneous tissue, but it doesn't typically present with a recent history of DVT.
  • Factitious disorder (Munchausen syndrome): Although rare, the possibility of self-induced injury or fabrication of symptoms should be considered, especially if the clinical presentation is atypical or inconsistent with expected findings.