Gout and the Foot

Gout is an extremely painful joint disease that affects about 3% of the population, mostly males. It is characterised by sudden attacks of joint inflammation (arthritis) caused by deposition of uric acid crystals in the joints. Though any joint in the body can be involved, the big toe joint is usually the first location and is affected in almost 75% of cases.

What causes gout?

Gout is related to an increased level of uric acid in the blood (hyperuricemia). Uric acid is a byproduct of purine digestion. Purines are nitrogen-based compounds, which form part of our genes and those of plants and animals. For this reason, purines are found in many foods; meat, especially liver and kidney, seafood and dried beans are rich in purines. Uric acid produced by the breakdown of purines enters the blood. When the kidneys filter the blood, they take out this uric acid and excrete it into the urine. However, if the body increases its production of uric acid or if the kidneys fail to properly eliminate the uric acid from the blood, its level in the blood increases. The uric acid crystals eventually precipitate in the joints causing gout.

It should be noted that not every person with raised uric acid levels develops gout, and in about half of gout cases the uric acid level in the blood is normal.

Risk Factors

Genetics; about 18% of patients have a family history of the disease

Gender; males are mostly affected, only 5% of cases are seen in females (mostly after menopause)

Age; more common in adults

Increased intake of purine-rich foods

Obesity; increased amount of body tissue available for breakdown -> increased uric acid production

Increased alcohol intake; alcohol interferes with uric acid elimination from the body

Diuretics or water pills that are used to treat high blood pressure can also precipitate gout.

Gout mostly affects the joints of foot, especially the big toe joint.

The attack usually starts at night and is so painful that it wakes up the patient. The reason for the attack occurring during sleep or affecting mostly the foot is that the body temperature decreases while one is asleep. As feet are elevated, blood flow decreases and this, in turn, decreases the temperature further. The decreased temperature facilitates the precipitation of crystals in the joint, which then trigger the inflammatory reaction.

Within 24 hours, the joint swells up, becomes hot and tender; the skin over the joint may also appear shiny and red and the pain spreads to the whole foot. Movement at the joint becomes restricted, this makes walking difficult and shoe size has to be adjusted accordingly. There may also be fever and malaise.

The disease progresses in four stages:

Hyperuricemia:
There is increased uric acid in the blood but no symptoms.

Acute Attack of Gout:
There is joint swelling and pain, which usually resolves in 3 to 10 days, even without treatment. The next attack may not occur for months or even years. However, with time, attacks become more frequent and last longer.

Interval period:
After the acute attack is over, the person is free of pain and the joint movement is normal.

Chronic Gout:
If not treated, the repeated attacks damage the joints permanently and the pain becomes constant. This takes a number of years and is a very debilitating condition, which requires surgical intervention.

Treatment:

In an acute attack:

Take high dose non-steroidal anti-inflammatory drugs (NSAIDs) e.g. naproxen or indomethacin

Steroids, usually prednisone; can be taken orally or injected at the joint

If both these drugs fail, colchicine is the drug of choice, which acts by preventing the deposition of uric acid crystals in the joints. It is also diagnostic of the disease because gout pain responds immediately to colchicine treatment.

To prevent future attacks, low dose NSAIDs or colchicine is prescribed for daily use.

High-risk individuals should avoid purine-rich foods, alcohol and maintain their weight. Taking vitamin C and other antioxidants, as well as consuming lots of cherries help to prevent gout attacks.

Gout can be made more comfortable by wearing a soft supportive insole. This supports and cushions the foot and places less strain on the joints of the foot. This results in less damage to the joints from the uric acid crystals.