(see also: Spondyloarthropathies)
- psoriasis affects 1-2 % of U.S. population & typically presents w/ well-defined erythematous scaly plaques;
- only a minority of pts with psoriasis develop arthritis;
- when arthritis develops, it most often is an asymmetrical oligoarthritis, which at times may be quite destructive;
- some patients may develop spondylitis (usually will have HLA-B27 antigen);
- incidence of MV prolapse is high ( > 50%);
- clinical course of psoriasis is long-term, w/ characteristic relapses & remissions;
- age: presents in 3rd-4th decade;
- gender: men and women are affected in equal numbers;
- circumscribed erythrematous maculopapules or silver scaling;
- activity of skin lesions may or may not correlate w/ of peripheral arthritis;
- skin lesions may appear similar to Reiter's Syndrome;
- subcutaneous nodules are absent;
- nail deformities: 80% of patients will have nail lesions, including nail pits and onycholysis;
- involves the small joints of feet and hands more than any other joint;
- dactylitis may involve degree of tenosynovitis as well;
- severe cases may progress to arthritis mutilans, w/ widespread destruction;
- calcaneal spurs, sclerosis, & periarticular erosions of MP joints;
- spontaneous fusions do not occur;
hand & wrist
- may have fusiform swelling of digits & nail changes;
- asymmetric joint involvement which affects terminal IP joints;
- DIP joint involvement.
- marked tendency for hand joints to becomes stiff;
- MP joints: become stiff in extension, rather than stiff in flexion as in RA;
- cartilage loss & erosions resemble changes seen in RA;
- symmetrical bony involvement with a predilection for DIP joints;
- erosive damage in the IP joints (presence of pencil-in-cup change);
- jonit destruction, widened joint spaces, & well defined adjacent bony surfaces;
- advanced cases reveal a "pencil in cup" deformity, tuft resorption, and eventual ankylosis;
- interphalangeal joint of the great toe is often involved;
- there is generally a lack of juxta-articular osteopenia;
- erosions are often para-marginal (where as in RA erosions are marginal);
Spine & SI Joint
- beaklike nonmarginal syndesmophytes are found (also seen in Reiter's);
- bilateral sacroilitis occurs in 10-30% of pts;
- paraspinal ligamentous calcification or ossification may occur similar to AS;
- non-steroidals and occasionally methotrexate or oral colchicine;
- sulfasalazine 1-2 gm per day has excellent efficacy;
- systemic steroids should be used with caution since these may cause skin lesions to become pustular;
- topical treatments:
- anthralin, corticosteroids, keratolytic agents;
- DIP joints are frequently spontaneously fused;
- nail deformity:
- w/ pitting, longitudinal ridging, consider intralesional corticosteroids;
- triamcinolone acetonide 5 mg/ml injected into nail fold q3-4 weeks;
- postoperative infection rates are higher than seen w/ RA
- Total knee arthroplasty in patients with psoriasis.
- Psoriatic arthritis in the hand.
- The psoriatic hand.
- Sulphasalazine in the management of psoriatic arthritis.
- Comparison of sulfasalazine and placebo in the treatment of psoriatic arthritis. A Department of Veterans Affairs Cooperative Study.
- Psoriatic arthritis: a quantitative overview of therapeutic options. The Psoriatic Arthritis Meta-Analysis Study Group.
- Sulphasalazine in psoriatic arthritis: a randomized, multicentre, placebo controled study.