Many people are surprised to hear that psoriasis, a condition that has historically always been associated with affecting the skin only, may in fact also be part of one of the more common causes of arthritis, known as psoriatic arthritis. Psoriatic arthritis is a condition that can be seen either with the typical skin changes of psoriasis and with associated pain and swelling of the joints or, alternatively, may present with pain and swelling of the joints without the skin lesions being present. It is only after evaluating the patient’s fairly typical joint presentations, performing further blood tests and X-rays that the diagnosis of psoriatic arthritis is made. If the correct diagnosis is missed, the patient is given more than one diagnosis and the treatment, which in recent times has become more beneficial and is capable of reversing the joint damage, is not utilized.
In many cases, there may well be a family history of psoriasis, especially in males, but females may also be subject to developing psoriasis and psoriatic arthritis. The condition may occur at any age, but it is often present at a very young age and usually presents by the time the patient reaches middle age. There is an association of a specific gene called HLA-B27, which when present causes the type of psoriasis arthritis that affects the spine in a similar way to ankylosing spondylitis. These patients present more commonly with neck and back pain rather than involvement of the peripheral joints. Another form of psoriatic arthritis mimics the arthritis seen in rheumatoid arthritis and will primarily affect the joints in the toes and hands. Classically, these patients may develop what we call “sausage toes” as their toes swell up like small cocktail sausages and very often there will be nail changes in the hands and the feet which help the physician to make the diagnosis. The condition is often aggravated by stress and worsens in the presence of other co-existing diseases.
The diagnosis is confirmed by typical X-ray findings. The X-rays show fairly specific abnormalities that are not necessarily seen in other forms of arthritis. The blood tests are nonspecific which in its own way is a diagnostic feature because in conditions such as rheumatoid arthritis one will usually have positive blood tests that support the diagnosis of rheumatoid arthritis. It is critical to make an early diagnosis and start conventional treatment using the so-called nonsteroidal anti-inflammatory drugs. The use of these drugs still forms a basis for the reduction in pain that is required, although they do not reverse the disease. In order to stop the disease from worsening, we use biologic therapies which allow us to dramatically reverse both the skin changes and the joint disease. We have made many patients with psoriatic arthritis much more functional and much less symptomatic.
Author: Norman B. Gaylis, M.D., F.A.C.P., M.A.C.R.