Description of Gout                                                                                        

Uric acid is a substance that normally forms when the body breaks down waste products (called purines). Uric acid is usually dissolved in the blood and passes through the kidneys into the urine. For people with gout, the uric acid level in the blood is so high that uric acid crystals form and deposit in joints and other tissues. This causes the joint lining to become inflamed, resulting in sudden and severe attacks of pain, tenderness, redness and warmth.

After several years, the crystals can build up in the joints and surrounding tissues, forming large deposits, called tophi. Tophi look like lumps under the skin and are often found in or near severely affected joints, on or near the elbow, over the fingers and toes, and in the outer edge of the ear.

Another condition, called pseudogout, is caused by deposits of calcium-based (instead of urate-based) crystals in the joints.

Causes and Risk Factors of Gout

In about 90 percent of all cases, gout is prevalent in men older than 40 and in menopausal women. An "episode" often occurs overnight, and within 12 to 24 hours, there is severe pain and swelling in the affected joint. The episode usually lasts about five to 10 days.

Although the exact cause is unknown, gout may be caused by:

An episode of gout can be triggered by:

Symptoms of Gout

Gout generally occurs in four (4) stages (asymptomatic, acute, intercritical and chronic) and has the following signs and symptoms:

Asymptomatic stage - urate levels rise in the blood, but produces no symptoms

Acute stage - symptoms usually lasting five to 10 days

Intercritical stage - symptom-free intervals between gout episodes. Most people have a second attack from six months to two years, while others are symptom-free for five to 10 years.

Chronic stage

Diagnosis of Gout

The diagnosis of gout is based on symptoms, blood tests showing high levels of uric acid, and the finding of urate crystals in joint fluid. In chronic gout, x-rays show damage to the cartilage and bones.

Figure 1