Diagnosis of Psoriatic arthritis

There are no definitive Laboratory tests for psoriatic arthritis.

  • Elevated ESR and CRP
  • anti-CCP antibodies
  • Uric acid level may be elevated
  • HLA-B27 (mostly found in the Axial Pattern of Disease)
  • pencil-in-cup appearance in x-ray
  • whiskering
  • telescoping digits
  • asymmetric sacroiliitis

The Caspar (Classification Criteria for Psoriatic Arthritis) Criteria

a patient must have inflammatory articular disease (joint, spine, or entheseal) with 3 points from any of the following:

  • Evidence of current psoriasis (2 points), a personal history of psoriasis (1 point), or a family history of psoriasis (1 point)
  • psoriatic nail dystrophy on current physical examination (1 point)
  • A negative RF(1 point)
  • Current dactylitis or history of dactylitis recorded by a rheumatologist(1 point)
  • Radiographic evidence of juxtaarticular new bone formation in the hand or foot(1 point)