Gout is a disease in which tissue deposition of monosodium urate crystals occurs in and about the joints with acute or chronic arthritis. It initially is seen in men aged thirty to sixty years. In women it usually occurs after menopause. But, gouty attacks can be precipitated by trauma, certain foods, alcohol intake, diuretics, and kidney failure. Kidney excretion is the major route of uric acid disposal.
Gout may be divided into the following phases: asymptomatic, acute gouty arthritis, intercritical gout (follows acute attack), and chronic tophaceous gout manifested by monosodium urate crystal (tophi) deposited in the soft tissues of the body.
Classifications of gout include primary-elevated serum urate levels or urate deposition appears to be a consequence of disorders of uric acid metabolism not associated with another acquired disorder, secondary-gout is a minor feature secondary to a genetic or acquired process, uric acid overproduction-about 10% of patients excrete excessive amounts of uric acid into the urine, and uric acid undersecretion-the majority of patients show a relative deficit in the renal excretion of uric acid.
Clinical features include acute gouty arthritis most commonly at the 1st metatarsophalangeal joint of the big toe. 10% of the patients have no recurrence, but up to 60% of patients experience a second attack in less than a year. The ankle, tarsal area and knee are commonly affected. Affected joints are usually red, hot, swollen, and extremely tender. Diffuse erythema is present. A patient may be awakened at night from the pain. High grade fever may be associated with acute attacks. The most common sites for tophi are the base of the great toe, Achilles tendon, elbow, knees, wrists, and hands. About 10-20% of patients with primary hyperuricemia develop uric acid kidney stones. Renal disease is the most common complication of gout except for the arthritis.
On x-ray one may see soft tissue swelling, and joint effusions, rat-bite erosions, cyst-like or punched-out erosions. Many lesions are expansile with overhanging margins(Martel's sign) that are displaced away from the axis of the bone. Joint spaces are preserved until late in the disease. Ankylosis and joint subluxation may occur in advanced cases. Gouty tophi (white, chalky crystals) may be seen within soft tissues.
The diagnosis of gout is confirmed by the presence of strongly negatively birefringent monosodium urate crystals identified on joint aspiration.
Treatment for acute gout includes colchincine, NSAIDS(indomethacin, sulindac, naprosyn, ketoprofen), corticosteroids, and glucocorticoids.
Treatment for chronic gout includes colchicines, allopurinol, and probenecid and sulfinpyrazone.
Prevention of recurrence can be obtained by avoiding foods high in purines like anchovies, organ meat, liver, spinach, mushrooms, asparagus, oatmeal, cocoa, sweetbreads, shellfish, beans, peas, and lentils as well as avoiding alcohol, aspirin, and diuretics.
Bibliography
- Banks, Alan S., et al McGlamry's Comprehensive Textbook of Foot and Ankle Surgery. Philadelphia:Lippincott Williams and Wilkins, 2001.
- Ferri, Fred F., The Care of the Medical Patient.Philadelphia:Mosby, 2001.