Psoriatic arthritis
Psoriatic arthritis: Excerpt from Handbook of Diseases
Psoriatic arthritis is a rheumatoid-like joint disease associated with psoriasis of the skin and nails. Although the arthritis component of this syndrome may be clinically indistinguishable from rheumatoid arthritis, the rheumatoid nodules are absent, and serologic tests for rheumatoid factor are negative. Some patients develop a more asymmetrical oligoarthritis affecting large or small joints. Psoriatic arthritis is usually mild, with intermittent flare-ups; however, in rare cases it may progress to crippling arthritis mutilans. This disease affects men and women equally; onset usually occurs between ages 30 and 35.
CLINICAL TIP: To help differentiate between psoriatic and rheumatoid arthritis, keep in mind that in psoriatic arthritis, the disease may be asymmetrical, psoriasis is pres-ent, and bone erosion with areas of “fluffy” new bone growth may be seen on X-ray films. Rheumatoid arthritis, however, is usually symmetrical, and X-ray films don’t show new bone formation.
Causes
Evidence suggests that predisposition to psoriatic arthritis is hereditary; 20% to 50% of patients are human leukocyte antigen-B27-positive. However, its onset may be precipitated by streptococcal infection or trauma.
Signs and symptoms
Psoriatic lesions usually precede the arthritic component; however, when the full syndrome is established, joint and skin lesions may recur simultaneously. Arthritis may involve one joint or several joints asymmetrically or symmetrically. Spinal involvement occurs in some patients. Peripheral joint involvement is most common in the distal interphalangeal joints of the hands, which have a characteristic sausage-like appearance. Nail changes include pitting, transverse ridges, onycholysis, keratosis, yellowing, and destruction. The patient may experience general malaise, fever, and eye involvement.
Diagnosis
Inflammatory arthritis in a patient with psoriatic skin lesions suggests psoriatic arthritis. X-rays confirm joint involvement and show:
❑ marginal erosion at interphalangeal joints with areas of thin, “fluffy” new bone formation
❑ “whittling” of the distal end of the terminal phalanges
❑ “pencil-in-cup” deformity of the distal interphalangeal joints
❑ relative absence of osteoporosis
❑ sacroiliitis
❑ atypical spondylitis with syndesmophyte formation, resulting in hyperostosis and paravertebral ossification, which may lead to vertebral fusion.
Blood studies indicate negative rheumatoid factor and elevated erythrocyte sedimentation rate and uric acid levels.
Treatment
In mild psoriatic arthritis, treatment is supportive and consists of immobilization through joint rest or splints, isometric exercises, paraffin baths, heat therapy, and aspirin and other non-steroidal anti-inflammatory drugs. Some patients respond well to low-dose systemic corticosteroids; topical steroids may help control skin lesions. More severe arthritis requires treatment with more powerful drugs called disease-modifying antirheumatic drugs.
Special considerations
❑ Explain the disease and its treatment to the patient and his family.
❑ Reassure the patient that psoriatic plaques aren’t contagious. Avoid showing revulsion at the sight of psoriatic patches — doing so will only reinforce the patient’s fear of rejection.
❑ Encourage exercise, particularly swimming, to maintain strength and range of motion.
❑ Teach the patient how to apply skin care products and medications correctly; explain possible adverse reactions.
❑ Stress the importance of adequate rest and protection of affected joints.
❑ Encourage regular, moderate exposure to the sun.
❑ Refer the patient to the Arthritis Foundation for self-help and support groups.
Book Source Details
- Book Title: Handbook of Diseases
- Author(s): Springhouse
- Year of Publication: 2003
- Copyright Details: Handbook of Diseases, Copyright © 2003 Lippincott Williams & Wilkins.
More About Osteoarthritis
More Medical Textbooks Online about Osteoarthritis
Review other book chapters online related to Osteoarthritis:
Copyright notice for book excerpts: Copyright © 2008 Lippincott Williams & Wilkins. All rights reserved.
|
|
More About This Book:
Title: Handbook of Diseases
Authors: Springhouse
Publisher: Lippincott Williams & Wilkins
Copyright: 2003
ISBN: 1-58255-266-5
|
|
» Next page: Rheumatoid arthritis (Handbook of Diseases)
Rate This Website
What do you think about the features of this website?
Take our user survey and have your say:
Website User Survey
Medical Tools & Articles:
Next articles:
Tools & Services:
Medical Articles:
Forums & Message Boards
- Ask or answer a question at the Boards:
