Psoriatic Arthritis Diagnosis
How Is Psoriatic Arthritis Diagnosed? continued...
When one or two large joints (such as knees) are inflamed, arthrocentesis can be performed. Arthrocentesis is an office procedure in which a sterile needle is used to withdraw (aspirate) fluid from the inflamed joints. The fluid is then analyzed for infection, gout crystals, and other inflammatory conditions.
X-rays may show changes of cartilage or bone injury indicative of arthritis of the spine, sacroiliac joints, or joints of the hands. X-ray findings include bony erosions resulting from arthritis although they tend not to look the same as in rheumatoid arthritis
The blood test for the genetic marker HLA-B27 can be found in more than 50% of patients with psoriatic arthritis who have spine inflammation.
Because psoriatic arthritis may lead to bone loss, a bone density scan may be taken to measure bone strength and to assess which patients may be at risk for osteoporosis and fractures.