Differential Diagnosis for Red Swollen Left Leg
- Single Most Likely Diagnosis
- Cellulitis: This is the most common cause of a red, swollen leg, typically resulting from a bacterial infection of the skin and soft tissues. It is often accompanied by warmth, pain, and sometimes fever.
- Other Likely Diagnoses
- Deep Vein Thrombosis (DVT): A blood clot in the deep veins of the leg can cause swelling, redness, and warmth. Risk factors include recent surgery, immobility, cancer, and genetic predispositions.
- Phlebitis: Inflammation of a vein, which can be superficial or deep, leading to redness, swelling, and warmth along the path of the vein.
- Eczema or Dermatitis: Skin conditions that can cause redness and swelling, especially if there is an allergic reaction or irritation.
- Insect Bite or Sting: Certain insect bites or stings can cause localized redness and swelling.
- Do Not Miss Diagnoses
- Necrotizing Fasciitis: A severe infection that destroys tissue under the skin, requiring immediate medical attention. It presents with severe pain, swelling, and redness, often with a feeling of the skin being tight.
- Compartment Syndrome: Increased pressure within a muscle compartment, which can lead to muscle and nerve damage. Symptoms include severe pain, especially on stretching the muscle, and swelling.
- Pulmonary Embolism (if DVT is suspected): A blood clot that breaks loose and travels to the lungs, which can be life-threatening.
- Rare Diagnoses
- Erythema Nodosum: An inflammatory condition characterized by the sudden formation of painful, red lumps on the skin, often on the legs.
- Lymphedema: Swelling caused by impaired lymph drainage, which can be primary (genetic) or secondary (due to surgery, infection, etc.).
- Panniculitis: Inflammation of the subcutaneous fat, which can cause redness, swelling, and pain in the affected area.
- Vasculitis: Inflammation of the blood vessels, which can cause a variety of symptoms including redness and swelling of the legs, depending on the vessels affected.