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The first time actor Jim Belushi's big toe swelled up, he thought he had jammed it while jogging. When it swelled up again a year later, it was even more painful. Belushi saw his doctor and was diagnosed with gout, a form of inflammatory arthritis.

Belushi's father and sister have gout, too, and his aunt suffered from a rare, severe form of the disease called refractory chronic gout (RCG). Luckily, Belushi did not develop RCG, which can cause joints to become very swollen, disfigured, and difficult to use.

As Belushi discovered while performing with Dan Aykroyd as the Blues Brothers one evening, gout can cause excruciating pain. Although Belushi was able to brush off the pain at home, on stage he realized he could barely put any weight on his affected foot.

After that experience, Belushi went to a rheumatologist who put him on a drug that blocks uric acid production, and the actor has been attack-free since then. He's the spokesperson for Check Out Your Gout, which Belushi describes as "a campaign to let people know that gout is a very painful condition that should be taken seriously, and to tell those affected by gout or RCG to check it out and work with a doctor to identify the best management plan."

What Is Refractory Chronic Gout?

Although most cases of gout are easily resolved with medication and dietary changes, refractory chronic gout, which affects around 120,000 Americans, is resistant to conventional gout medications.

RCG patients have more frequent gout flares. They also develop tophi, hardened uric acid crystals that form large, disfiguring lumps in the hand and foot joints. Tophi can erode bone, causing permanent arthritis.

Uric acid is a chemical byproduct created by the body when breaking down proteins called purines, which are found in virtually all foods. Typically, uric acid dissolves in the blood, travels to the kidneys, and is excreted in urine. In RCG patients, however, uric acid fails to break down completely and forms crystals in the bloodstream that get stuck around joints.

Who Gets Refractory Chronic Gout?

Known as "the disease of kings" because of famous gout sufferers Henry VIII and Charlemagne, gout is not actually caused only by overindulgence in meat and alcohol as was believed for many years. There is likely a genetic component.

As Belushi discovered, gout runs in families -- but only about three percent of people who experience a gout attack will develop refractory chronic gout. Doctors don't know yet why some members of a family with gout develop RCG and others don't.

Men typically experience their first gout attack between 40 and 55 (Belushi was 42). Women contract gout less frequently than men, and almost always after menopause. It could take several months or even years to experience a second attack, although around 60 percent of patients will have another attack within a year.