Gout (basic)
What is gout?
Gout refers to joint pain and inflammation associated with the accumulation of crystalline uric acid in the body.
With proper treatment, gout is manageable.
Without treatment, gout can cause permanent damage to the joints as well as the kidneys.
What causes gout?
Gout can occur when uric acid levels in the body are too high (hyperuricemia).
Typically, uric acid is formed as a byproduct of specific metabolic processes. Uric acid produced by the body dissolves in the bloodstream.
Kidneys filter the blood, removing metabolic wastes (including uric acid) and excess fluids and salts to form urine. Urine is eliminated, excreting uric acid from the body. Thus, uric acid does not accumulate in the blood.
In certain circumstances, however, uric acid levels in the body can increase, resulting in hyperuricemia.
Although most people with hyperuricemia do not develop gout, gout can occur when hyperuricemia leads to the crystallization of uric acid in the bloodstream. Once formed, needle-like uric acid crystals can accumulate in joint spaces, causing pain and inflammation.
What are the risk factors associated with hyperuricemia and gout?
- Family history of gout
- Overweight/obesity
- Alcohol abuse
A diet high in purine-rich foods:
- Dried beans and peas
- Anchovies
- Sardines
- Brains
- Liver
- Kidneys
- Gravies
- Environmental or occupational exposure to lead
Use of certain medications:
- Diuretics
- Salicylates (such as aspirin)
- Nicotinic acid
- Cyclosporine (used to prevent organ transplant rejection)
- Levodopa (used in the treatment of Parkinson's disease)
What are the symptoms of gout?
Gout occurs in four stages, each with characteristic symptoms:
- Asymptomatic hyperuricemia
- Acute gout/acute gouty arthritis
- Interval/inter-critical gout
- Chronic tophaceous gout
What is asymptomatic hyperuricemia?
With asymptomatic hyperuricemia, high blood levels of uric acid (hyperuricemia) are present.
No other symptoms occur, and treatment usually is not necessary.
What are the symptoms of acute gout?
Gout reaches the acute stage after uric acid has crystallized and accumulated in the joints.
Accumulation of uric acid crystals leads to the occurrence of acute gouty attacks.
Acute attacks:
- Are characterized by sudden intense joint pain and inflammation (swelling, warmth, tenderness)
- Often occur at night
- It often affects the joints of the big toe first, but it also may affect the instep, ankles, heels, knees, wrists, fingers, or elbows
Symptoms of the first attack may improve without treatment for 3 to 10 days. Months or years may pass before a second attack occurs.
In many cases, second and future attacks grow:
- More frequent
- More severe/prolonged
- More destructive to the joints
What is the inter-critical stage?
During the inter-critical stage (between attacks):
- No symptoms are present
- Joint function is normal
What are the symptoms of chronic tophaceous gout?
If left untreated for an extended period (10 or more years), gout can advance to a chronic, disabling stage.
Symptoms of chronic gout include:
- Tophi (singular, tophus): hard or gritty uric acid deposits under the skin. Tophi occur most often around the joints and at the rim of the ear
- Kidney stones
- Permanent joint damage
- Permanent kidney damage
With proper treatment, gout rarely progresses to the chronic stage.
How is gout diagnosed?
Sudden symptoms of joint inflammation can suggest gout.
Diagnosis is confirmed by examining fluid from the affected joint (synovial fluid) to check for uric acid crystals.
How is gout treated?
Treatment of gout can include both:
- Behavior modifications
- Medications