rheumatology dermatology

CASPAR Criteria (Psoriatic Arthritis)

Classification criteria for psoriatic arthritis (PsA) using the CASPAR criteria. Score >=3 with inflammatory articular disease = PsA.

Inflammatory articular disease (joint, spine or entheseal) — required*

Psoriasis — highest that applies: current (+2); else personal history (+1); else family history in a first- or second-degree relative (+1)*

Typical psoriatic nail dystrophy (onycholysis, pitting, hyperkeratosis) on current examination*

Rheumatoid factor negative (any method except latex; ELISA or nephelometry preferred)*

Dactylitis — current swelling of an entire digit, or a history recorded by a rheumatologist*

Juxta-articular new bone formation on hand or foot X-ray (excluding osteophytes)*

Score interpretation

Not Applicable — No Inflammatory Articular Disease -1

CASPAR applies only to established inflammatory articular disease (joint, spine or entheseal).

→ Assess for inflammatory arthritis first; dermatology review if psoriasis suspected.

PsA Not Classified 0–2

Score < 3: does not meet CASPAR criteria for PsA

→ Consider seronegative RA, reactive arthritis, or gout; dermatology review if psoriasis suspected

Psoriatic Arthritis Classified 3–6

Score ≥ 3: meets CASPAR criteria for psoriatic arthritis

→ Rheumatology referral; DMARDs (methotrexate first-line); consider biologic if inadequate response; dermatology co-management for skin disease

Interpretation bands for the CASPAR / PsA. Apply clinical judgement and local guidance.

Curated clinical cross-links plus same-class fallbacks.

Drugs

Pathways

Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.