Gout is a form of inflammatory arthritis which is caused by deposition of monosodium urate monohydrate crystals in and around the synovial joints. This form of arthritis develops in people who have high level of uric acid in their blood (Hyperuricemia).
This is more commonly found in men than women. Risk of developing gout increases with age and increasing level of serum uric acid.
Risk factors for gout
1. Men – Gout has male preponderance, male to female ratio is 5:1. Gout is more commonly develop in men with age group between 40 and 50.
2. Women after menopause – Gout can develop in older women means after menopause increase risk of developing gout in women.
3. Person who has high level of uric acid in blood.
4. Family history – Usually many people having gout has the positive family history.
5. Medical conditions – people with some medical problems related with kidney, hypertension, diabetes, obesity and liver disorders are more prone to develop gout.
6. Metabolic syndrome
7. High alcohol intake
8. Generalized osteoarthritis
9. Diet high in red meat or fructose, low in vitamin C and coffee.
Causes of gout
We can divide the causes of increase level of uric acid in body in to three parts; decreased renal excretion or increased intake or overproduction of uric acid.
1.Decreased renal excretion because of
• Increased renal tubular reabsorption
• Renal failure
• Lead toxicity
• Lcatic acidosis
• Drugs such as thiazide diuretics and loop diuretics, Aspirin, Cyclosporine and pyrazinamide
• Red meat
• Sea food
• Vegetables containing high purine content such as spinach, asparagus, peas, dried beans, cauliflower etc
3.Overproduction of uric acid
• Myeloproliferative and lymphoproliferative disorder
• High fructose intake
• Glycogen storage disease
• Inherited disorder; Lesh -Nyhan syndrome (HPRT mutations)
Signs and Symptoms
Gout has classic presentation of acute, sudden and severe pain in first MTP joint (big toe) usually come without warning, during the attack the joint or area becomes hot, red, swollen and extremely tender.
Most common joint involved is MTP, other sites are ankle, mid foot, knee, elbow, wrist.
Clinical features of pain
Rapid and acute onset, reaching maximum severity within 2 – 6 hours.
Pain usually awakens the patient in the early morning.
Patient often describes it as worst pain ever.Pain feels like volcano fire
Extreme tenderness, such that patient is unable to touch feet on the ground or anywhere, he can’t wear his socks on.
Marked swelling with overlying red and shiny skin.
Self-limiting, takes 10 -14 days in complete resolution
Apart from severe pain patient may have mild fever, malaise and confusion.
Gout may be
• Acute gout – Because of increasing level of uric acid, acute attack of severe pain is known as acute gout.
• Chronic gout – Chronic inflammation of one or more joints because of increasing deposition of uric acid crystals known as tophi.
Tophi may be deposited in joints and in soft tissues. Common places of deposition of tophi are extensor surfaces of fingers, hands, forearm, elbows, Achilles tendons and sometimes the helix of the ear. Tophi are white in color. Tophi can ulcerate, discharging white gritty material, become infected or induce a local inflammatory response, with erythema and pus in the absence of secondary infection.
How to diagnose?
Characteristic feature of pain usually indicate Gout but for confirmation and to rule out other types of arthritis some investigations are necessary.
Aspiration of fluid from the joint space – Aspirate will show crystals of uric acid under microscope, bursa or tophi.
In acute attack fluid shows increased turbidity due to high neutrophils.
In chronic gout fluid may be white due to high crystal load.
Blood test to measure high level of uric acids.
Biochemical screen which include renal function test, lipid profile and uric acid to know any metabolic syndrome.
Elevated ESR, CRP and neutrophilia in acute gout.
Radiographs are usually normal in acute gout, but well demarcated erosions in patients with chronic gout or tophaceous gout may be seen.
X ray, ultrasound and MRI are useful to see the soft tissue swelling and any destruction if it is.
Aim of management is to relieve pain during gout attack and maintaining uric acid level below 6mg/dl by giving urate lowering drugs.
1. NSAIDS are simple pain reliever usually prescribed to relieve pain during acute attack of gout.
2. Local ice packs also suggested to relieve pain.
3. For recurrent episodes Colchicine is effective but it has some side effects such as nausea, vomiting and diarrhea.
4. Joint aspiration and intraarticular injection of steroids followed by early mobilization are very effective in acute attacks of gout.
5. Urate lowering therapy for patients who have high level of uric acid crystals with recurrent attacks of gout. Allopurinol is a xanthine oxidase inhibitor; starting dose should be 100mg per day and in older patients 50 mg per day. The dose of Allopurinol should be increased by 100mg every four weeks and 50 mg in elderly and those with renal impairment.
Febuxostat is a xanthine oxidase inhibitor which is useful in patients who fail to respond with allopurinol. Because of hepatic metabolism of this drug, no need to adjust the dose in patients with renal problems. It is more effective than allopurinol and starting dose is 80 mg per day.
6. Pegloticase is a biological treatment which is indicated for the treatment of tophaceous gout resistant to standard therapy and is administered as intravenous infusion every 2 weeks for up to six months. Side effects are infusion reactions (which can be treated by antihistamines and steroids) and flares of gout during first three months.
Annual monitoring of uric acid is recommended to prevent the attack of gout and to adjust the dose of urate lowering drug.
In addition to drug treatment predisposing /triggering factors should be avoided such as
Drink plenty of water to remove uric acids from the body.
Diet with high purine content should be avoided such as meats, seafood, vegetables like spinach, mushroom, asparagus, cauliflowers, oatmeal, dried beans, lentils, should be taken in limited amount.
Alcoholic beverages should be avoided.
Add low fat dairy products in your diet.
Follow healthy lifestyle with diet plan and exercise. (Read health tips)
Please note: Any medical information published on this website is not intended as a substitute for informed medical advice and you should not take any action before consulting with a health care professional.
Content source – Davidson’s Principles and Practice of Medicine(22nd edition), gout .com