New 4-item scale helps detect psoriatic arthritis

Access to the full content of this site is available only to registered healthcare professionals. Access to the full content of this site is available only to registered healthcare professionals.

Takeaway

  • The Psoriatic arthritis UnclutteRed screening Evaluation (PURE)-4 scale, based on 4 symptoms, has high diagnostic value for psoriatic arthritis (PsA) in patients with psoriasis.

Why this matters

  • Up to 15.5% of patients with psoriasis have undiagnosed PsA, suggesting need for a short and easy-to-perform screening tool.

Key results

  • Evocative signs of dactylitis (OR, 23.1; P=.050), inflammatory heel pain (OR, 12.7; P=.0003), bilateral buttock pain (OR, 9.9; P=.008), and peripheral joint pain with swelling in patients aged
  • ≥1 positive item on PURE-4 was associated with 85.7% sensitivity, 83.6% specificity, positive predictive value of 48.7%, negative predictive value of 97.0%, and area under the receiver operating curve of 87.6% for diagnosis of PsA.

Study design

  • 137 patients with psoriasis (15.3% with PsA) were analyzed by the PURE-4 scale to determine its diagnostic utility.
  • The 4 items included in PURE-4 were selected by multivariate logistic regression from an initial group of 23 items identified from the literature review.
  • Funding: MSD France.

Limitations

  • Small patient sample size.
  • No external validation.