When the body produces excess uric acid or excretes it too slowly in the urine, it builds up and forms sharp, needle like crystals that deposit in a joint and surrounding tissue, causing pain, inflammation and swelling in these joints – this is gout.
The big toe is one of the commonest joints to be affected. Gout affects 0.5 per cent of people at any one time.
Uric acid is formed from the breakdown of substances called purines – found naturally in our bodies as well as in certain foods. Gout is caused from too much uric acid in the blood, which then gets deposited into joints as sharp, pointy, uric acid crystals.
Risk factors for developing gout include:
- Lifestyle factors: Alcohol consumption. Obesity. Eating certain foods – Uric acid is formed from purines (form part of protein), which are found naturally in many foods e.g. red meats, liver, kidneys, anchovies, herring.
- Medical conditions and medications: Diabetes. High cholesterol. Medications such as some of the drugs used to treat high blood pressure e.g. Thiazide diuretics (water pills). Illnesses resulting in prolonged bed rest. Less commonly, longstanding kidney disease may result in high blood levels of uric acid.
- Chemotherapy drugs for cancer.
- Genetics: High levels of uric acid can be part of the inherited make-up of some families and some people are just born with a tendency to contract gout. One out of four people with gout have a family history of the ailment.
- Age and sex: Gout occurs most often in men. Female hormones (oestrogen and progesterone) seem to help prevent gout because women rarely get gout until after the menopause – the time at which women stop making female hormones. Men are most likely to first experience gout between the ages of 30 and 50. Women aren’t likely to develop gout until they are between the ages of 50 and 70.
Symptoms of gout centre around red, painful, swollen, joints and the main features are:
- Gout is usually extremely painful
- Gout begins suddenly
- Gout often involves the big toe but can involve the ankle, knee, elbow and other joints
- Gout usually only involves one joint
Tests used to confirm the diagnosis of gout include:
- Uric acid blood levels: A simple blood test that will often show high levels of uric acid.
- X-Rays: These would usually be done to exclude other problems, since X-Rays are usually normal in uncomplicated gout.
- Joint fluid testing: This is the definitive test and involves removing (with a syringe) some fluid from the affected joint and looking at it under a microscope: uric acid crystals will be seen.
Lifestyle changes help people to avoid gout attacks:
- Avoid eating too much animal protein: These are rich sources of purines – the precursors of uric acid – and include organ meats (liver, brains, kidney and sweetbreads), red meat, anchovies, herring and mackerel. Smaller amounts are found in fish and poultry.
- Maintain a healthy weight: Gradual weight loss will lessen the load on affected weight-bearing joints. Losing weight may also decrease uric acid levels. Avoid fasting or rapid weight loss because doing so may temporarily raise uric acid levels.
- Watch your alcohol consumption: Consuming too much alcohol can inhibit the excretion (getting rid of, mainly via the urine) of uric acid, and an attack of gout. Limit alcohol to no more than two drinks a day if you’re a man. Limit alcohol to one drink a day if you’re a woman. Ideally, avoid alcohol.
- Keep yourself well hydrated: Fluids help to dilute uric acid in your blood and urine.
- Treatment of the acute attack includes anti-inflammatories, steroids (sometimes) and other more specialised options sometimes. Rest is essential in an acute attack.
- To prevent further attacks, therapy directed at normalising uric acid levels in the blood should be considered for patients who have had multiple gout attacks. Several drugs that help the kidneys eliminate uric acid are available, such as probenecid and a drug that blocks production of uric acid by the body, such as allopurinol is commonly used. These preventive treatments tend to be effective, safe, and inexpensive, for most patients but long-term compliance is often necessary to avoid attacks.
Gout can progress in three ways:
- Recurrence and Remission. Attack-period of health-attack. Approximately 50 per cent of people who have had gout will get it again. Thankfully, long periods of remission between attacks are common but this can be quite variable and often relates to diet, alcohol, obesity, and compliance with treatment.
- Chronic Gouty Arthritis is a condition where joints are permanently damaged as a result of ongoing gout. It can be a crippling disease but is very rare in these days of good modern treatment.
- Kidney stones. Uric acid crystals (the cause of gout) can form kidney stones and cause renal colic (the painful result of having a kidney stone).
Gout is rarely a major ongoing problem for people who comply with treatment. Serious complications are uncommon today although compliance with treatment remains important.
Written by Dr Colin Burns