Gout: Joint Pain and More

By CEJ2
Content provided by the Faculty of the Harvard Medical School

It starts with a bang, often in the dead of night. The pain is severe, almost unbearable, and fever may make you feel even worse. Lying still helps a bit, but even the touch of a sheet can be excruciating. And, worst of all, your distress may be greeted with a sly smile instead of supportive sympathy. You are suffering from gout, a common disease that's often misunderstood.

Myths and realities

Gout is an old disease, and erroneous beliefs about it are almost just as old. The name, in fact, is based on a misconception It's derived from a Latin word that means "a drop"; ancient physicians chose the name because they believed the pain resulted from a drop of "a bad humor." Over the centuries, gout was considered a rich man's disease, a product of overeating, excessive drinking, and corpulence. Modern research, however, shows that gout has no relationship to wealth or social status and little to diet and drink. But one traditional view has proved correct: Gout is a man's disease, occurring seven to nine times more often in men than women. It's also a common disease, striking an estimated 3.4 million American men annually. That makes gout the most prevalent form of inflammatory arthritis in men older than 40.

The chemical culprit

Gout is caused by an accumulation of uric acid. Uric acid has no useful function in the human body; it is simply a breakdown product of purines, a group of chemicals present in all body tissues and many foods. In normal circumstances, the body rids itself of uric acid by excreting it in the urine, keeping blood levels low. But some men have inherited a metabolic glitch that allows blood uric acids to rise; 90% of the time it's because the kidneys don't excrete enough uric acid, but sometimes the body just produces too much of the pesky chemical. Certain medications, such as low-dose aspirin, thiazide diuretics, and niacin, can also increase uric acid levels. Binge drinking, prolonged fasting, kidney disease, lead toxicity, extreme muscular exertion, and leukemia and lymphomas are much less frequent causes of high uric acid levels.

These high levels lead to gout — but not right away. In fact, uric acid levels are typically elevated for 20 to 30 years before they cause any trouble, which is why gout usually occurs in middle-aged and older men. Uric acid levels are normally below 7 milligrams per deciliter (mg/dL). The higher the level, the more likely an attack of gout; men with levels above 10 mg/dL have a 90% chance of developing gout. But gout can also be triggered by a rapid drop in uric acid levels, which is why up to 30% of men with gout have normal uric acid levels at the time of an attack.

An attack of gout occurs when excess uric acid is deposited in a joint and forms urate crystals that irritate the joint lining. White blood cells try to help; they gobble up the crystals, but they are not equal to the task. The white blood cells are themselves damaged, releasing chemicals that cause inflammation, swelling, and pain.

Ouch

Gout is painful, very painful.

The most common manifestation of gout is acute arthritis, severe pain in a joint. In most cases, it strikes one joint at a time; in half, it's the first joint in the large toe. Other frequent sites include the forefoot, instep, heel, ankle, and knee. Gout is uncommon in the upper body, but it can strike fingers, wrists, and elbows. At any site, the attack usually begins abruptly, often at night. Within hours, the joint becomes red, swollen, hot, and painful. The pain and tenderness can be so severe that even gentle pressure from bedding is a problem. And even though only one small joint is affected, the inflammation can be intense enough to cause fever, muscle aches, and other flu-like symptoms.

Without treatment, gout can also cause long-term arthritis, with chronic swelling and permanent joint damage. Urate crystals can build up to a remarkable degree, producing large, even grotesque, deposits called tophi in joints and other tissues. Crystals may also be deposited in the kidneys, and they may precipitate in the urine, forming kidney stones.

Your Guide to Gout


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Gout – a painful type of arthritis – often first takes aim at the big toe. It also attacks other parts of the body, including fingers, wrists, elbows, knees, ankles, and heels, causing stiff and swollen joints.