Psoriatic arthritis (psoriasis arthropathica) is a chronic arthritis that occurs in association with psoriasis (psoriasis). Often psoriatic arthritis affects the finger or toe joints. These cause pain and show inflammatory thickening. About one in five people with psoriasis suffer from psoriatic arthritis. When psoriasis is associated with nails (nail psoriasis), the risk of developing psoriatic arthritis is doubled. Read more about psoriatic arthritis here.
Psoriatic Arthritis: Different forms
Four out of five sufferers have had psoriasis for several years prior to the onset of psoriatic arthritis (psoriasis arthropathica). As a rule, psoriasis skin inflammation spreads to parts of the joints causing psoriatic arthritis. These may be the skin of the joint, the bone, the periosteum and the appendages of joint capsules, tendons or ligaments. In about every fifth case, however, psoriatic arthritis already occurs before the skin symptoms or completely without skin symptoms.
The exact relationship between psoriasis of the skin and psoriatic arthritis has not yet been clarified. Physicians distinguish three sub-forms of psoriasis arthropathica, which differ in terms of frequency, preferably affected joints and complications of each other:
- Peripheral asymmetric type
- Peripheral symmetric type
- Axial type
Psoriatic arthritis – Symptoms: Peripheral asymmetric type
Many psoriatic arthritis suffer from an asymmetric, painful swelling and movement inhibition of the finger and toe joints. The symptoms associated with psoriatic arthritis are often confused with rheumatism or gout and usually appear years after the first skin lesions. Men and women are about equally affected in this form. Often the eyes (inflammation of conjunctiva or iris) are involved.
Psoriatic arthritis – Symptoms: Peripheral symmetric type
Less frequently, doctors observe the form of psoriatic arthritis, the symptoms of which appear symmetrically (bilaterally) on the larger joints from the clavicle to the ankle joint. Mostly skin and joint symptoms occur at the same time. Even with this form of psoriasis arthropathica, the eyes can also get sick.
Psoriatic Arthritis – Symptoms: Axial type
In this rare form of psoriatic arthritis, inflammatory symptoms occur in the spine or in the pelvic sacral joints of the pelvis. This can lead to a stiffening of these joints. Often, this form of psoriasis joint arthritis is mistaken for ankylosing spondylitis.
Diagnosis of psoriatic arthritis
It often takes a long time for the final diagnosis of psoriatic arthritis. Often the diagnosis is considered to be certain only if characteristic skin and nail changes of psoriasis are present and the so-called rheumatism factor can not be detected in the blood. If the rheumatism factor is present, this indicates rather a rheumatoid arthritis.
As part of the diagnosis doctors use mostly imaging techniques such as X-ray and ultrasound, magnetic resonance imaging (MRI) or joint scintigraphy. However, especially at the beginning of psoriatic arthritis, these often do not show any conspicuous findings. Nevertheless, the recordings can be helpful in the further course: they can be used to document and evaluate the changes that have caused psoriatic arthritis.
Therapy of psoriatic arthritis
In mild cases, cortisone-free anti-inflammatory and analgesic medications may be used in psoriatic arthritis (non-steroidal anti-rheumatic drugs, NSAIDs). In some cases physicians also prescribe physiotherapy or orthopedic aids for arthropathic psoriasis. If a joint is acutely inflamed, they often prescribe cortisone tablets and / or ointments. In some cases, cortisone is also injected directly into the affected joint. However, cortisone is only suitable for long-term use in exceptional cases.
People with psoriatic arthritis often receive DMARDs (Disease Modifying Antirheumatic Drugs) as basic therapy. These include methotrexate, leflunomide, ciclosporin A and sulfasalazine. They dampen the excessive response of the immune system, which is (partly) responsible for the symptoms of psoriatic arthritis. Very often, doctors use methotrexate (MTX) because this drug is already used in the treatment of Psoriatic arthritis has proven.