| GOUT: Family Member of Arthritis
Gout
Arthritis is an umbrella term referring to a broad class of diseases affecting the joint which is associated with joint inflammation. Gout is one of the common forms of inflammatory arthritis. It is due to the accumulation of uric acid crystals in the body and typically affects the metatarsophalangeal joint in the big toe.
Gout is a clinical syndrome characterised by acute arthritis and associated with hyperuricaemia. Over the years, it is reported that the prevalence of gout has been increasing at an alarming rate around the globe, with an incidence of 0.58-2.89 per 1000 people in a year.
Men and postmenopausal women have a higher risk of gout. In Malaysia, researchers found that gout often occurs in the Malay ethnic group.
| What are the causes of gout?
Gout can be classified into 2 categories according to the causative factor:
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Primary gout: Inborn enzymatic defects causing hyperuricaemia
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Secondary gout: Other primary disorders such as chronic renal failure leading to hyperuricaemia
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Generally, gout is caused by the overproduction of uric acid in the body or the underexcretion of uric acid from the body, ultimately leading to hyperuricaemia. Subsequent deposition of the uric acid crystals in the joint triggers the inflammatory response.
Purines are aromatic organic compounds consisting of two rings fused together. They are synthesised in the body to produce the building blocks of DNA and RNA. Excess purines are degraded by xanthine oxidase into uric acid. Besides being synthesised naturally in the body, purines can also be obtained through food such as internal organs and meat. Thus, these foods should be avoided or limited to prevent gout in people with a risk of hyperuricaemia. Furthermore, alcohol and certain drugs could also lead to gout. Generally, the risk factors for gout include:
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Increasing age
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Sex (Men and postmenopausal women)
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Alcohol
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Family history of gout
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Drugs (E.g., low-dose aspirin, diuretics, beta blocker, anti-rejection drugs)
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Obesity
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Purine-rich diet
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Hypertension
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Diabetes
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Recent surgery or trauma
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Renal insufficiency
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Early menopause
| Purine, the precursor of uric acid
Typically, the metatarsophalangeal joint in the big toe is affected by gout due to the slow blood flow and low temperature in this region. Solubility of uric acid reduces with decreasing temperature, leading to the deposition of crystals in the joint. However, gout can also be found in other joints, including the knee and elbow.
| What are the symptoms of gout?
Gout attacks can happen out of the blue with severe pain. Symptoms of the affected joint include intense pain, tenderness, redness, swelling, and warmth of the joint.
| Why metatarsophalangeal joint?
Typically, the metatarsophalangeal joint in the big toe is affected by gout due to the slow blood flow and low temperature in this region. Solubility of uric acid reduces with decreasing temperature, leading to the deposition of crystals in the joint. However, gout can also be found in other joints, including the knee and elbow.
| How is gout treated?
Gout is typically treated with allopurinol to reduce the uric acid level in the body. Allopurinol acts as a suicide inhibitor that competes with purines to irreversibly bind to the active site of xanthine oxidase. Subsequent conversion of allopurinol to oxypurinol by the enzymes inhibits the enzyme, decreasing the uric acid level in the body.
In addition, drugs like colchicine and nonsteroidal anti-inflammatory drugs (NSAIDs) are also used to reduce inflammation and pain of the affected joint.
| Prophylaxis is better than cure
In a nutshell, gout is a rising issue that should be given attention to. As the saying goes, prevention is always better than cure, practicing a healthy lifestyle and avoiding alcohol, keeping a healthy diet and body weight are indeed important to prevent gout. Last but not least, seek assistance from your healthcare provider if there is the development of gout-related symptoms in your body!
References
Dehlin, M., Jacobsson, L., & Roddy, E. (2020). Global epidemiology of gout: prevalence, incidence, treatment patterns and risk factors. Nature Reviews Rheumatology, 16(7), 380–390. https://doi.org/10.1038/s41584-020-0441-1
Gout: What Is It, Symptoms, Causes, Treatment. (n.d.). Cleveland Clinic. https://my.clevelandclinic.org/health/diseases/4755-gout
Gout - Symptoms and causes. (2021, March 6). Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/gout/symptoms-causes/syc-20372897
Sulaiman, Wahinuddin & Wahida, Nurul & Zuki, Md & Zamri, Norshamiza & Sugathan, Sandheep & Chandran, Aris & Ong, Ping & Seung,. (2019). EPIDEMIOLOGY AND MANAGEMENT OF GOUT PATIENTS ATTENDING RHEUMATOLOGY TERTIARY CENTRE IN PERAK, MALAYSIA.