History: The most characteristic lesion of gout is the tophus, a deposit of crystals of monosodium urate that triggers a severe inflammatory reaction in the surrounding tissue. Although the first metatarsophalangeal joint is the most common site of initial inflammatory disease, visible tophi can also develop on the helix of the ear, olecranon bursa, Achilles tendon, extensor surface of the forearm, prepatellar bursa, fingertips, and toes.