Arthritis, Psoriatic
Basics
A chronic, destructive, seronegative arthropathy in patients with long-standing psoriasis
Description
- Psoriatic arthritis (PsA) is a seronegative spondyloarthropathy characterized by inflammatory arthritis and enthesitis.
- Five patterns of arthritis in PsA:
- Asymmetric oligoarthritis: <5 joints
- Distal interphalangeal (DIP) joint predominant: osteoarthritis-like, associated with nail psoriasis
- Symmetric polyarthritis: may be indistinguishable from rheumatoid arthritis (RA)—typically milder
- Spondyloarthritis: asymmetric and discontinuous, unlike ankylosing spondylitis (AS)
- Arthritis mutilans: destructive, resorptive arthritis; produces “opera-glass” or “telescoping” digit
- Psoriasis may be limited in extent.
- Course of arthritis and extent of psoriasis do not correlate.
- Other extra-articular features, such as iritis, are less common.
- Damaging joint disease may occur in 40–60%. Characteristic radiologic changes include “pencil-in-cup” deformity and periostitis.
- Rheumatoid factor (RF) and anti–cyclic citrullinated peptide (anti-CCP) antibody are usually negative. HLA-B27 may be positive.
Epidemiology
- Peak onset age: 30 to 50 years
- Predominant gender: female = male
- Polyarthritis is more common in women.
- Spondylitis in up to 25%, more common in males
- Psoriasis precedes arthritis in most patients by an average of 12 years. Arthritis preceding psoriasis occurs in up to 15% of patients, usually children. Arthritis and psoriasis may present simultaneously.
- Psoriasis occurs in 2–3% of the U.S. population; 6–42% will develop PsA (1).
Prevalence
Prevalence: 1 to 2/1,000 population (1)
Etiology and Pathophysiology
- CD4+/CD8+ T cells; tumor necrosis factor α (TNF-α); interleukin 1 (IL-1), IL-6, IL-8, IL-10, IL-17 and IL-23; and matrix metalloproteases present in synovial fluid
- Osteoclast precursor cell upregulation
- Unknown. Probably multifactorial: immunologic, genetic, environmental factors
Genetics
- 30–40% concordance in identical twins
- HLA-B27 in 15–50% with PsA (spondylitis pattern) versus 90% in AS
- Other HLA associations in PsA: HLA-B7, HLA-B38, HLA-B39, HLA-Cw6
Risk Factors
- Psoriasis
- Family history of PsA
- Obesity
General Prevention
No known prevention strategies; unknown whether early treatment of psoriasis prevents onset of PsA
Commonly Associated Conditions
Psoriasis
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Citation
Domino, Frank J., et al., editors. "Arthritis, Psoriatic." 5-Minute Clinical Consult, 33rd ed., Wolters Kluwer, 2025. Medicine Central, im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/1688464/all/Arthritis_Psoriatic.
Arthritis, Psoriatic. In: Domino FJF, Baldor RAR, Golding JJ, et al, eds. 5-Minute Clinical Consult. Wolters Kluwer; 2025. https://im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/1688464/all/Arthritis_Psoriatic. Accessed October 13, 2024.
Arthritis, Psoriatic. (2025). In Domino, F. J., Baldor, R. A., Golding, J., & Stephens, M. B. (Eds.), 5-Minute Clinical Consult (33rd ed.). Wolters Kluwer. https://im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/1688464/all/Arthritis_Psoriatic
Arthritis, Psoriatic [Internet]. In: Domino FJF, Baldor RAR, Golding JJ, Stephens MBM, editors. 5-Minute Clinical Consult. Wolters Kluwer; 2025. [cited 2024 October 13]. Available from: https://im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/1688464/all/Arthritis_Psoriatic.
* Article titles in AMA citation format should be in sentence-case
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T1 - Arthritis, Psoriatic
ID - 1688464
ED - Domino,Frank J,
ED - Baldor,Robert A,
ED - Golding,Jeremy,
ED - Stephens,Mark B,
BT - 5-Minute Clinical Consult, Updating
UR - https://im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/1688464/all/Arthritis_Psoriatic
PB - Wolters Kluwer
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DB - Medicine Central
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