Differential Diagnosis for Unilateral Foot and Ankle Swelling
Single Most Likely Diagnosis
- Cellulitis: This is a common and likely cause of unilateral foot and ankle swelling, often resulting from a bacterial infection of the skin and soft tissues. It is characterized by redness, warmth, swelling, and pain in the affected area.
Other Likely Diagnoses
- Deep Vein Thrombosis (DVT): DVT can cause unilateral swelling of the foot and ankle due to a blood clot in the deep veins, which can lead to obstruction of blood flow.
- Trauma or Injury: A recent injury, such as a sprain or fracture, can cause swelling in the foot and ankle.
- Lymphedema: This condition involves the abnormal accumulation of protein-rich fluid in the interstitial tissue, leading to swelling, often affecting one limb.
- Gout or Pseudogout: These conditions can cause sudden, severe swelling and pain in the foot and ankle, often affecting the big toe.
Do Not Miss Diagnoses
- Compartment Syndrome: A serious condition that occurs when pressure within the muscle compartments increases, leading to inadequate blood supply to the tissues. It requires prompt diagnosis and treatment to prevent permanent damage.
- Osteomyelitis: A bone infection that can cause swelling, pain, and redness in the affected area, which can lead to serious complications if left untreated.
- Necrotizing Fasciitis: A life-threatening infection that affects the tissue beneath the skin and surrounding muscles and organs, requiring immediate medical attention.
Rare Diagnoses
- Erythromelalgia: A rare disorder characterized by burning pain, heat, and redness in the hands and feet, which can also cause swelling.
- Klippel-Trenaunay Syndrome: A rare congenital condition that affects blood vessels, soft tissues, and bones, leading to swelling, pain, and other symptoms in the affected limb.
- Lipedema: A rare condition characterized by the abnormal accumulation of fat in the legs, which can cause swelling, pain, and other symptoms.