Gout is painful inflammation of a joint as a result of build up of crystals within the joint. The crystals are made of uric acid, a substance that is found in many foods and usually excreted by the kidneys. People who produce too much uric acid, or whose kidneys do not excrete it enough, are predisposed to the development of gout. When the levels of uric acid in the blood are high enough, it begins to collect as crystals in joints which leads to pain and swelling. Gout most often affects the base of the big toe, but can affect any joint. It tends to recur in repeated attacks of acute inflammation.
The diagnosis of gout is often suggested on the basis of the history and physical exam. A sample of joint fluid can be obtained with a needle and examined under a microscope. The urate crystals can then be seen. This is also the best way to make sure the joint is not infected, or inflamed due to another condition.
Acute attacks of gout are treated with anti-inflammatory medications. Sometimes a steroid injection is given directly into the joint to relieve pain and swelling, or steroids are taken orally. Colchicine is a medication that can help an attack of gout resolve faster. Some patients then take a daily medication to decrease the level of uric acid in their blood to prevent attacks of gout.
Repeated attacks of gout tend to last longer, and the pain may not go away entirely. Eventually the bones of the joint can be damaged, and large collections of urate crystals can accumulate under the skin and cause nodules.