CASPAR criteria for Psoriatic arthritis
What are the current classification criteria for Psoriatic arthritis?
Always keep in mind that the purpose of classification criteria in rheumatology is to standardize patients for clinical trials. Nonetheless, they can be useful in making the diagnosis of PsA. The most widely used criteria are the Classification of Psoriatic Arthritis (CASPAR) criteria. The Moll and Wright criteria and European Spondyloarthropathy Study Group criteria are also used, but CASPAR has the highest sensitivity. CASPAR presumes a clinical assessment of inflammatory arthritis.
The CASPAR criteria are:
- 1. Evidence of psoriasis (current, past, family): two points if current history of psoriasis, one point others.
- 2. Psoriatic nail dystrophy: one point
- 3. Negative rheumatoid factor: one point.
- 4. Dactylitis (current, past history): one point.
- 5. Radiographic evidence of juxtaarticular new bone formation: one point.
Three or more points have 99% specificity and 92% sensitivity for diagnosis of PsA.