Gout affects approximately 8 million Americans, according to the American College of Rheumatology. It is an extremely painful rheumatic disease caused by deposits of uric acid in a joint or in the surrounding connective tissue.
Uric acid is a waste product produced as the body breaks down purines, common substances found in meats, fish, and many other foods. Normally, uric acid dissolves in the blood, passes through the kidneys, and is eliminated in the urine. But overproduction of uric acid or its inefficient removal by the kidneys allows uric acid levels to build up, causing a condition called hyperuricemia. The excess uric acid then accumulates as needle-like crystals inside a joint.
The symptoms of a gout attack are impossible to ignore—sudden stabbing pain and swelling in one joint, which frequently begins in the middle of the night. The affected joint is warm, red, and very tender to the touch. An initial gout attack typically involves a joint in the foot, especially at the base of the big toe. Other common sites of gout attacks are the ankle, instep, heel, knee, wrist, finger, or elbow. A gout attack may be triggered by alcohol, certain medications (aspirin, some diuretics, niacin, immunosuppressants, levodopa), an illness, or a stressful event.
Gout is believed to have a genetic component. According to the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), many people with gout have a family history of the disease. Other risk factors are gender (men, particularly those between ages 40 and 50, are more likely to develop gout than women); age (it is more common in adults than in children); being overweight; excessive consumption of alcohol; the presence of kidney disease, high blood pressure, high cholesterol or diabetes; and exposure to lead.
A high consumption of some purine-rich foods also increases gout risk. Purine-rich foods include poultry, liver, dried beans, and certain meats, fish and vegetables. Organ meats such as sweetbreads, liver, and kidney are of greatest concern for people with gout and should be avoided. In addition, limiting serving sizes of beef, lamb, and pork, and seafood with high-purine content, such as sardines and shellfish, is recommended.
A mild to moderate acute attack of gout typically is treated with an nonsteroidal anti-inflammatory drug (NSAID) or with corticosteroids (oral or injected). If these medications do not relieve the symptoms, colchicine, an older drug, may be prescribed. Colchicine, which has a number of unpleasant side effects, is more effective if given within 24 hours of the onset of the attack.
Treatment with allopurinol (Lopurin, Zyloprim) or febuxostat (Uloric) is recommended for people with hyperuricemia. If those drugs are contraindicated, probenecid (Probalan) may be substituted. Individuals with severe chronic gout who do not respond to these treatments may benefit from pegloticase (Krystexxa), a newer medication that lowers uric acid levels by a different mechanism than these other drugs.