Differential Diagnosis for Arm Swelling with Pain at the Wrist and Elbow

Single Most Likely Diagnosis

• Cellulitis or Soft Tissue Infection: This is a common condition that can cause swelling and pain in the arm, especially if there's a history of trauma or infection. The presence of redness, warmth, and tenderness would support this diagnosis.

Other Likely Diagnoses

• Deep Vein Thrombosis (DVT): Although more commonly associated with the legs, DVT can occur in the arms, especially in individuals with risk factors such as central venous catheters, cancer, or recent surgery. Swelling and pain in the arm are key symptoms.
• Lymphedema: This condition, characterized by the abnormal collection of protein-rich fluid in the interstitial tissue, can cause swelling of the arm. It often occurs after lymph node removal or radiation therapy.
• Gout or Pseudogout: These conditions can cause sudden, severe pain and swelling, typically affecting the joints. While more commonly associated with the lower extremities, they can also affect the wrists and elbows.
• Rheumatoid Arthritis or Other Autoimmune Disorders: These conditions can cause pain, swelling, and stiffness in multiple joints, including those in the arm.

Do Not Miss Diagnoses

• Compartment Syndrome: A medical emergency that occurs when pressure within the muscle compartments increases to the point of compromising blood flow. It can cause severe pain, swelling, and potentially lead to permanent damage if not promptly treated.
• Neoplastic Conditions (e.g., Lymphoma, Leukemia): Certain cancers can cause swelling and pain in the arm due to lymph node involvement or direct tumor effects.
• Infective Endocarditis: Although less directly related to arm swelling, this condition can lead to septic emboli that might cause arm pain and swelling.

Rare Diagnoses

• Thoracic Outlet Syndrome: A condition involving compression, injury, or irritation of the nerves and/or blood vessels (arteries and veins) in the thoracic outlet area, which can cause pain and swelling in the arm.
• Vasculitis: Inflammation of the blood vessels, which can cause a variety of symptoms including arm pain and swelling, depending on the vessels affected.
• Sarcoidosis: A condition that can cause inflammation in various parts of the body, including the lymph nodes, which might lead to arm swelling and pain.