Gout

What is it?

According to NIAMS: gout is an inflammatory joint disease characterised by recurrent attacks of joint pain and swelling, occurring when urate builds up in the body and forms “needle-like crystals” in the joints, often beginning in the big toe or lower limbs. MedlinePlus describes it as arthritis that causes pain, swelling and redness, usually in one joint at a time, and an attack may last a week or two. The CDC states that it often affects one joint, frequently the big toe, and that attacks are followed by symptom-free periods called remission.

According to MedlinePlus: with early diagnosis, treatment and lifestyle change, gout is “one of the most controllable forms of arthritis”. This page does not cover specific prevalence figures.

Causes

According to NIAMS: urate is a substance in the body that comes from purines found in body tissues and food. Gout occurs when the body produces too much urate or does not excrete enough of it in the urine. According to MedlinePlus: uric acid is a waste product the body makes when it breaks down purines, and when the kidneys cannot filter enough of it, crystals form in the joints and cause inflammation. The NHS states that it can run in families.

Risk factors

According to NIAMS: male sex, advancing age, menopause, alcohol and sugar-sweetened drinks and foods high in purines (especially from animal sources), obesity, metabolic syndrome, chronic kidney disease, high blood pressure and conditions with rapid cell turnover, medicines such as diuretics, low-dose aspirin, high-dose niacin and ciclosporin, family history, and rare inherited conditions (Kelley-Seegmiller and Lesch-Nyhan syndromes).

MedlinePlus adds heart failure, purine-rich foods (red meat, organ meats and some seafood), fructose-rich drinks and immunosuppressants. The NHS adds high cholesterol, diabetes, osteoarthritis and previous joint surgery or injury. The CDC lists insulin resistance, impaired kidney function, beer and spirits, and states that men are more affected.

Symptoms

According to NIAMS: “gout attacks often start suddenly at night, and the severe pain may be enough to wake you”. The joint becomes swollen, red and warm, and the attack usually passes within one to two weeks with varying intervals between attacks. The NHS describes sudden severe pain in a joint, often the big toe, which may affect the foot, ankle, hand, wrist, elbow or knee, with hot, swollen, red skin over the joint.

How is it diagnosed?

According to NIAMS: review of the medical history, symptoms, medicines and risk factors, a joint examination, measuring the blood urate level, taking a sample of fluid from one of the painful joints to look for urate crystals, and imaging tests (ultrasound or CT) to detect crystal deposits. MedlinePlus lists joint fluid analysis and measuring uric acid in blood or urine. The NHS states that if the result is not clear the patient may be referred to a rheumatologist and other tests done.

• Uric acid testLab test

Treatment

The treatment categories usually used are listed here; this is not a prescription. The doctor chooses the plan according to each person's condition; do not change any medicine or dose without a specialist.

According to NIAMS, for acute gout attacks: anti-inflammatory medicines (prescription or over the counter), colchicine, and corticosteroids. The NHS lists non-steroidal anti-inflammatory drugs such as ibuprofen, or steroids, and the CDC lists acetaminophen. To treat hyperuricaemia: xanthine oxidase inhibitors, uricosuric agents, and uricase. The doctor determines the class and dose according to your condition and other diseases, and do not start or stop a medicine without consulting them.

According to NIAMS: “taking the medicines your doctor prescribes for this purpose regularly is the key to preventing gout attacks”. The NHS says uric acid-lowering medicines are given when attacks recur.

During an attack according to NIAMS and the NHS: apply ice to the area (up to 20 minutes according to the NHS) to reduce swelling and pain, raise the limb and rest the joint, drink enough water, avoid pressure on the joint, and take the prescribed medicine early.

Follow-up

According to NIAMS: sticking to the prescribed urate-lowering medicines is the key to preventing attacks, and cardiovascular complications are watched by keeping a healthy weight and diet. This page does not cover specific follow-up test intervals or urate target levels.

Complications

According to NIAMS: untreated chronic gout may cause tophi, which are hardened crystal deposits that permanently damage the joint. NIAMS links it to high blood pressure, chronic kidney disease, diabetes, kidney stones, heart attack and congestive heart failure. The NHS lists joint damage, painful nodules and kidney stones, and MedlinePlus lists among associated conditions kidney stones, chronic kidney disease and pseudogout (joint inflammation from calcium pyrophosphate deposits).

Prevention

According to NIAMS: lose weight by cutting calories and exercising, reduce alcohol (including non-alcoholic beer), avoid sugar-sweetened drinks, reduce red meat and organ meats, avoid high-purine seafood (shellfish, sardines and anchovies), and follow the DASH pattern rich in vegetables, fruit, whole grains and low-fat dairy. The NHS adds quitting smoking and exercise that does not strain the joints, losing weight gradually and avoiding crash diets. The CDC recommends moderate physical activity of 150 minutes a week.

Living with it

According to the CDC and NIAMS: between attacks there are periods of remission, but continued control of urate, diet and weight reduces the frequency of attacks and their complications. This page does not cover figures on recurrence rates.

Common questions