Differential Diagnosis for Acute Left Wrist Swelling without Injury or Trauma

Single Most Likely Diagnosis

• Gout: This is a common cause of acute, painful swelling in the wrist, especially if there's no history of trauma. Gout can cause sudden, severe attacks of pain, swelling, redness, and tenderness, often occurring at the base of the thumb or other joints.

Other Likely Diagnoses

• Pseudogout (Calcium Pyrophosphate Deposition Disease, CPPD): Similar to gout, pseudogout can cause acute, painful swelling in joints, including the wrist, without a history of trauma.
• Rheumatoid Arthritis (RA): Although RA typically involves multiple joints and has a more gradual onset, it can occasionally present with sudden swelling in a single joint, including the wrist.
• Infectious Arthritis: Bacterial, viral, or fungal infections can cause acute joint swelling and pain. The wrist is less commonly affected than other joints, but it's still a possibility, especially if there's an open wound or compromised immune system.
• Osteoarthritis: While typically a chronic condition, osteoarthritis can have acute exacerbations leading to swelling, especially if there's a sudden increase in activity or minor, unnoticed trauma.

Do Not Miss Diagnoses

• Septic Arthritis: This is a medical emergency that requires prompt diagnosis and treatment. It can present with acute joint swelling, pain, and fever, and can lead to severe joint damage if not treated promptly.
• Lyme Arthritis: Caused by the bacterium Borrelia burgdorferi, Lyme disease can lead to arthritis, which may present as acute swelling in a single joint, including the wrist, especially in endemic areas.
• Hemarthrosis: Bleeding into the joint space can occur spontaneously in patients with bleeding disorders or those on anticoagulant therapy, leading to acute swelling.

Rare Diagnoses

• Hemochromatosis: A genetic disorder leading to iron overload, which can cause arthritis, including wrist involvement, though it's less common.
• Sarcoidosis: A condition that can cause inflammation in various parts of the body, including the joints, leading to swelling and pain.
• Amyloidosis: A group of diseases that can cause abnormal proteins (amyloid) to accumulate in various organs, including joints, leading to swelling and pain, though joint involvement is rare.
• Neoplastic or Paraneoplastic Syndromes: Certain cancers can cause joint swelling as a paraneoplastic syndrome or due to direct invasion of the joint by tumor cells, which is rare but important to consider in the differential diagnosis.