Gout: Symptoms, Causes, Treatment, Prevention
Gout: what is it? :
Gout is a disorder of purine metabolism characterized by deposition of uric acid crystal in joints and periarticular tissue. Gout is one of the 3 crystal deposition disorders. Other crystal deposition disorders are ‘pseudo gout’ and ‘calcium hydroxyapatite deposition disorder’.
Types of gout:
Gout is of 2 types.
- Primary gout (95%)
- Secondary gout (5%)
Gout is also classified as:
- Acute gout
- Chronic gout
Causes of gout:
Primary gout has no known definite cause. It has some predisposing factors:
- Age: specially between 2nd and 4th decade of life
- Sex: male:female ratio is 15:1
- Alcohol (more lactic acid→ more uric acid→ gout)
- Drugs: hydrochlorothiazide, cyclosporine, ethambutol, pyrazinamide etc.
- Over eating
- Renal failure
Sources of uric acid which is responsible for gout:
Endogenous (70%): from purine metabolism
Exogenous (30%): from purine rich diet such as liver, brain, kidney, heart (in short, all organ meats).
Pathogenesis of gout:
- Disorder of purine metabolism causing hyperuricemia.
- Deposition of sodium urate crystals in articular and periarticular structures.
- Crystals produce inflammatory reaction.
- There is erosion of bones and cartilages.
- Pannus (Granulation tissue) formation within joint cavity.
- Fibrous ankylosis of joint.
- Irregularity of articular surface may lead to secondary osteoarthritis.
Symptoms of gout:
- Sudden onset of severe sharp pain in affected joint. Usually gout appears first in metacarpophalangeal joint of great toe. Pain lasts for hours to weeks.
- Pain is so severe that patient may not allow even to touch the affected area.
- Tophus formation in various areas of body. Size of tophi may be 2-20 cm.
- Stiffness of joint.
Investigations for gout:
- TC, DC, ESR (increases)
- Blood uric acid (increased)
- Arthrocentesis and examination of joint fluid under polarized microscope to see urate crystals which are small rod or pin shaped.
- X ray: at first stage of gout, there is no findings, later, joint space is seen reduced, erosion of bone and cartilage is seen (as in osteoarthritis)
Treatment of gout:
General treatment of gout:
- Bed rest
- Purine diet restriction
- Alcohol restriction
- Plenty of water intake
Drugs for gout:
- Intra articular steroid injection
- High dose aspirin (5-6 gm/day)
- Sulphin pyrazone
Operative treatment for gout:
- Excision of gout lesion
- Arthrodesis in functional position
Prevention of gout:
- Plenty water intake
- Less taking purine diet
- Control blood pressure
- Control obesity
- Avoid alcohol
- Diuretics should be used stealthily
- Kidney care