The goals with testing are to identify gout, to distinguish it from other conditions, such as other types of arthritis that may have similar symptoms, and to investigate the cause of increased uric acid concentrations in the blood.
- Synovial fluid analysis – used to detect the needle-like crystals derived from uric acid, other crystals that may be present, and to look for signs of joint infection.
- Uric acid – to detect elevated levels in the blood; if a diagnosis of gout is made, uric acid testing may be performed regularly to monitor levels.
- Basic Metabolic Panel (BMP) – this group of tests or just the components BUN and creatinine may be used to evaluate and monitor the person's kidney function.
- Complete blood count (CBC) – to determine if there is an abnormally large increase in the number of white blood cells (leukocytosis) in the blood, to help differentiate between septic arthritis and gout.
- Sometimes other tests, such as an RF (rheumatoid factor) or an ANA (anti-nuclear antibody) test may be ordered to rule out other causes of arthritis symptoms. A blood culture and/or synovial fluid culture may be ordered if septic arthritis is suspected.
- X-rays of the affected joints may show uric acid deposits and damage indicative of gouty arthritis.