With the introduction of biological agents, effective systemic treatments are available for psoriatic arthritis. The dermatologist or rheumatologist will evaluate the patient’s psoriatic arthritis to determine the most suitable treatment on a case to case basis.
Diagnosis of Psoriatic Arthritis
The first step would be diagnosis of the psoriatic arthritis:
- Typical clinical signs and symptoms
- Rule out the main joint diseases that come into differential diagnosis of Psoriatic arthritis: Rheumatoid arthritis, Reiter’s syndrome.
- Perform relevant laboratory tests like X rays, blood tests etc. to confirm the diagnosis
Goals of Treatment in Psoriatic Arthritis
- Control the joint pain and swelling
- Reduce the joint damages
- Minimize or prevent disability
Treatment Options for Psoriatic Arthritis
- Nonsteroidal anti-inflammatory drugs(NSAIDs) such as ibuprofen and naproxen help in symptomatic relief of pain, swelling and stiffness of the joints
- Disease-modifying anti-rheumatic drugs(DMARDs) such as methotrexate and cyclosporine relieve severe symptoms and attempt to slow or stop joint and tissue damage. These drugs are immunomodulators and have to be used under the supervision of a dermatologist.
- Oral methotrexate is one of the most effective treatments for psoriatic arthritis. It is toxic to liver after a cumulative total dose of 1.5 gm, especially so in alcoholics, obese individuals and those on intravenous drug abuse. While using methotrexate, lab tests for liver, kidney and bone marrow functions should be carried out every 3 months and liver biopsy done after every 1.5 gm cumulative dose. Usual dosage of methotrexate in psoriasis is 7.5mg (total)weekly in three 12 hourly divided doses. Some patients responds well to this dosage, if not, the dosage is doubled after 2-4 weeks. 80% improvement is seen with methotrexate. Once the joint inflammation responds and the swelling and pain disappear the dosage is gradually reduced for a minimum effective dosage.
- Cyclosporine, though not as effective as methotrexate, is effective at a dosage of 3-5 mg per kg body weight per day. Hepatotoxicty is less, but it is toxic to kidneys, hence continuous monitoring of blood pressure and serum creatinine levels are mandatory.
- Systemic Retinoids, acitretin and isotretinoin,are also effective in treating psoriatic arthritis.
- Biologic agentsare a new group of medications whichtarget specific immune system pathways. Etanercept is highly effective for psoriatic arthritis, but less so for psoriasis plaques. Infliximab is proving very effective for treating both psoriatic arthritis and psoriasis, but may activate latent tuberculosis in patients. Alefacept is moderately effective but provide longer remissions than others. Efalizumab is effective in both, but rebounds are common. These agents have provided much relief to patients with severe and long standing psoriasis and psoriatic arthritis, but long term safety is yet to be determined.
- Sulfasalazine is more effective in joint disease than psoriasis skin disease. Gold salts and intramuscular sodium thiomalate have also been proven to be effective in controlling the disease activity in psoriasis joint disease.
- Associated treatments likelocal applications and massage, phototherapy , exercise and physiotherapy programs are used in conjunction for the treatment of psoriatic arthritis. Surgery may be required when joint mobility is compromised.
Prognosis of Psoriatic Arthritis
A 10 year follow up study suggested that psoriatic arthritis produced less pain and disability compared to rheumatoid arthritis. In a Canadian study of 220 patients with psoriatic arthritis, however, deforming erosive joint disease was found in 40% of cases. Indicators of poor prognosis of psoriatic arthritis include young age of onset, extensive skin involvement, HIV infection, large number of joint involvement and association with certain genes at HLA B27, B39 and DLW3.
Early recognition and early institution of suitable therapy, then, is the watch word in the treatment of psoriatic arthritis.
Next: How To Avoid Psoriasis Flare Ups
Related Reading
Reference
- Psoriasis, in Rook’s Textbook of Dermatology, 7th Edition, 2004
- Philip M, Bernard SG. Diagnosis and Treatment of Psoriatic Arthritis.J Am Acad Dermatol 2005;52:1-19.
Disclaimer
The information given in this article is for educational purpose only so that patients are aware of the options available. No diagnosis should be made or treatment undertaken without first consulting your doctor. If you do so, the author or suite101 will not be responsible for any consequences. The images provided are for illustration purpose only.
