Gout: Causes, symptoms and treatment
What is gout?
Gout is a common form of arthritis where crystals form in and around joints causing pain, swelling and redness.
Gout often affects the big toe, but can also affect other joints including knees, ankles, elbows, thumbs or fingers.
Gout affects around 1 in 45 people in the UK, and is more common in men than it is in women. When women develop gout, it is usually after the menopause.
Image: Dr P Marazzi/Photo Researchers, Inc.
Attacks of gout can be unexpected and excruciatingly painful. With prompt treatment, the pain and inflammation usually disappear after a few days, but they may recur at any time.
Crystal deposits in the joints
Gout is the body's reaction to irritating crystal deposits in the joints. Here, uric acid crystals have affected the base of the joint of the big toe.
X-ray image: eMedicine.com, 2008
The pain can be intense, but treatment usually works very well.
In mild cases attacks may be prevented by diet alone, but recurring attacks of gout may require long-term medication to prevent recurrent attacks and damage to bones and cartilage and deterioration of the kidneys.
Chronic gout sufferers may feel tiny, hard lumps accumulating over time in the soft flesh of areas such as the hands, elbows, feet or earlobes. These deposits, called tophi, are concentrations of uric acid crystals and can cause pain and stiffness over time. If similar deposits form in the kidneys, they can lead to painful and potentially dangerous kidney stones.
What are the symptoms of gout?
Symptoms of gout usually strike unexpectedly. They typically do not last more than 10 days but may recur. Although less common, some patients may have chronic pain due to gout. Symptoms of a gout attack may include:
- Sudden, intense pain in a joint, typically the big toe or ankle, sometimes the knee, hand or wrist
- Swelling, inflammation and a feeling that the joint is very hot
- Extreme tenderness of the joint to even the lightest touch
- Red or purple skin around the joint
- In extreme cases alternating chills and fever
- With recurring attacks soft fleshy growths may appear, called tophi, which are accumulations of uric acid crystals.
Over time gout attacks may occur more frequently, involve more joints, have more severe symptoms and last longer.
What causes gout?
An excess of uric acid in the blood brings on gout. Uric acid comes from two places - produced by the body and from the diet. Any extra uric acid usually filters through the kidneys and gets passed in the urine. If the body produces too much uric acid, or fails to excrete it, crystals form and become concentrated in the joints and tendons. This causes swelling, pressure and severe pain.