Gout

A common metabolic disorder that causes attacks of arthritis, usually in a single joint (most commonly the base of the big toe). Gout is due to high levels of uric acid in the blood (see hyperuricaemia); the arthritis is due to the deposition of uric acid crystals in joint tissue. The affected joint is red, swollen, and tender. Attacks last a few days and often recur. They are sometimes accompanied by fever. Gout may be associated with kidney stones (see calculus, urinary tract), and affects 10 times more men than women. In men, it occurs any time after puberty; in women it usually occurs after the menopause. The condition tends to run in families. The diagnosis is confirmed by tests on blood or fluid from the affected joint to measure uric acid levels. Pain and inflammation can usually be controlled by nonsteroidal anti-inflammatory drugs or colchicine. If these are ineffective, a corticosteroid may be injected into the joint. Long-term treatment with drugs such as allopurinol or probenecid can stop or reduce the frequency of attacks.