Gout

Gout (also called gouty arthritis, Greek name: podagra, from pod - foot and agra - trap) is a form of arthritis caused by the accumulation of uric acid crystals in joints. It is an intensely painful disease, which in most cases affects only one joint (monoarthritis), most commonly the big toe.

Diagnosis

The diagnosis is generally made on a clinical basis, although tests are required to confirm the disease.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Hyperuricemia is a common feature; however, urate levels are not always raised (Sturrock 2000). Hyperuricemia is defined as a plasma urate (uric acid) level greater than 420 μmol/L (7.0 mg/dL) in males ( the level is around 380 μmol/L in females ); despite the above, high uric acid level does not necessarily mean a person will develop gout. Additionally, urate falls to within the normal range in up to 2/3 of cases (Siva et al 2003). If gout is suspected, the serum urate should be repeated once the attack has subsided.Other blood tests commonly performed are full blood count, electrolytes, renal function and erythrocyte sedimentation rate (ESR). This serves mainly to exclude other causes of arthritis, most notably septic arthritis.

Related Topics:
Plasma - Uric acid - Full blood count - Electrolyte - Renal function - Erythrocyte sedimentation rate - Arthritis - Septic arthritis

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

A definitive diagnosis of gout is from light microscopy of joint fluid aspirated from the joint (this test may be difficult to perform) to demonstrate intracellular monosodium urate crystals in synovial fluid polymorphonuclear leukocytes. The urate crystal is identified by strong negative birefringence under polarised microscopy, and their needle like morphology. A trained observer does better in distinguishing them from other crystals.

Related Topics:
Diagnosis - Light microscopy - Intracellular - Synovial fluid - Polymorphonuclear leukocytes

~ ~ ~ ~ ~ ~ ~ ~ ~ ~