Gout with normal uric acid levels: Although uric acid levels are normal, gout can still occur, especially during acute attacks when uric acid levels may not always be elevated. The presentation of a swollen, red great toe is classic for gout.

Septic arthritis: Bacterial infection of the joint can cause swelling, redness, and pain, similar to gout. Normal uric acid levels do not rule out this diagnosis.
Trauma or injury: A recent injury to the toe could cause swelling and redness, and the absence of elevated uric acid levels does not exclude this possibility.
Inflammatory arthritis (e.g., rheumatoid arthritis, psoriatic arthritis): These conditions can cause joint inflammation and swelling, which might present similarly to gout in the great toe.

Osteomyelitis: Bone infection can present with localized redness, swelling, and pain. Although less common, missing this diagnosis could lead to serious complications.
Cellulitis: A bacterial skin infection that can spread and become severe if not treated promptly.
Deep vein thrombosis (DVT): While less common in the toes, DVT can cause swelling and redness and is a potentially life-threatening condition if not recognized and treated.

Pseudogout (calcium pyrophosphate deposition disease): Although this condition can mimic gout, it is less common and typically involves larger joints, but it could potentially affect the toe.
Sarcoidosis: A systemic disease that can cause joint inflammation and might present with swelling and redness in the toes, though this is uncommon.
Tumor or cyst: Benign or malignant tumors, or ganglion cysts, could cause localized swelling and redness, though these are rare causes of a swollen, red great toe.