Differential Diagnosis for Foot Swelling, Redness, and Pain
Single Most Likely Diagnosis
- Cellulitis: This is a common bacterial skin infection that can cause redness, swelling, and pain in the affected area, including the foot. The symptoms presented are classic for cellulitis, making it the most likely diagnosis.
Other Likely Diagnoses
- Deep Vein Thrombosis (DVT): DVT can cause swelling, pain, and redness in the foot and leg due to a blood clot in the deep veins. It's a common condition, especially in individuals with risk factors such as recent surgery, immobility, or cancer.
- Gout: Gout is a form of arthritis characterized by sudden, severe attacks of pain, swelling, redness, and tenderness in one or more joints, often occurring at the base of the big toe. It's a likely diagnosis if the patient has a history of gout or has risk factors such as diet or family history.
- Insect Bite or Sting: An insect bite or sting can cause localized redness, swelling, and pain. This is a common and usually benign condition but can be severe in cases of allergic reactions.
Do Not Miss Diagnoses
- Necrotizing Fasciitis: Although rare, necrotizing fasciitis is a life-threatening infection that requires immediate medical attention. It can present with severe pain, swelling, and redness, and can rapidly progress to gangrene and death if not treated promptly.
- Osteomyelitis: This is an infection of the bone that can cause pain, swelling, and redness in the affected area. It's a serious condition that requires prompt antibiotic treatment to prevent long-term damage.
- Compartment Syndrome: This is a condition where increased pressure within a muscle compartment leads to inadequate blood supply to the tissues inside the compartment. It can cause severe pain, swelling, and pallor, and is a medical emergency requiring immediate intervention.
Rare Diagnoses
- Erythromelalgia: A rare disorder characterized by burning pain, heat, and redness in the hands and feet. It can be primary or secondary to other conditions such as myeloproliferative disorders.
- Complex Regional Pain Syndrome (CRPS): A chronic pain condition that most often affects one of the arms, legs, hands, or feet after an injury or trauma. It's characterized by intense burning or aching pain, swelling, and changes in skin temperature and color.
- Lymphedema: A condition characterized by swelling in one or more extremities, resulting from impaired flow in the lymphatic vessels or lymph nodes. It can cause chronic swelling, pain, and redness in the affected limb.