Gout — does it looks like Rheumatoid Arthritis?

Abstract

Characteristically in gout the feet and hands are commonly involved with a very asymmetric (random) polyarticular joint involvement. Radiographs shows varying densities due to calcium precipitation with the urate crystals. Erosions can occur in a very sporadic asymmetric distribution. Borders can be sclerotic because of the indolence of the process, creating a punched-out or “mouse bitten” appearance, overhanging edges, bony enlargement, and irregular spicules at the sites of tendon and ligament attachments can also be present. Joint spaces are preserved until late and there is no osteopenia. Some patients with advanced gout have such large deposits of urate crystals in periarticular tissues and bone, causing erosion and destruction that may resemble a lytic tumor on radiographs. Usually, soft-tissue swelling, and other signs readily establish the diagnosis. The authors report several cases of arthritic hand caused by gout to describe the typical radiographic findings. Complementary studies as well as a review of the literature are presented to report the differences between gout and AR. All the patients presented with painful, swollen, hot and tender several hand joints, usually in both hands. Some deposits of urate crystals were found but no skin ulceration. Treatment began with resting the joint and applying ice, NSAIDS, corticosteroids and colchicine. Healthy diet low in purines (from alcohol, meat, fish) was recommended. Serial clinical reevaluations and plain radiographs were done. The radiographic studies showed asymmetric and polyarticular joint involvement. Varying densities were seen on radiographs due to calcium precipitation with the urate crystals. Erosions, sclerotic borders and a “mouse bitten” appearance were, also, found. Joint spaces were preserved even with the joints partially destroyed. Despite multiple erosions, there is no osteopenia evident in the patients. These patient's hands characteristically had an asymmetric polyarticular joint involvement. Urate crystals deposits and erosions were seen, also with asymmetric distribution. The “mouse bitten” appearance, sclerotic borders and erosion was seen in the older patients. Joint spaces were well preserved in the youngers. In contrast to rheumatoid arthritis, mineralization was maintained and there was no predominant periarticular osteopenia. There are several differences between gout and AR-asymmetric polyarticular joint involvement, Urate deposits and “mouse bitten” appearance, irregular spicules at the sites of tendon and ligament attachments and no osteopenia.