Psoriasis, a Skin Disease, can also be Arthritis

Dr. Norman B. Gaylis

Many people are surprised to hear that a condition, namely psoriasis, that has been historically always associated with affecting the skin only, may in fact also be one of the more common causes of arthritis. It is known as psoriatic arthritis.

This is a condition that may be seen with either the typical skin changes of psoriasis with associated pain and swelling of the joints or alternatively may in fact at times present itself with pain and swelling of the joints without the skin lesions being present. It is only after evaluating the patients fairly typical joint presentation, 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 much more beneficial and is capable of reversing the joint damage, is not utilized.

In the characteristic cases there may well be a family history of psoriasis, particularly on the male side passed from males to males. However, it is not specific to males only, as many females may also be subject to developing psoriasis and psoriatic arthritis.

The condition may occur at any age. It is often present at a very young age and usually has manifested itself by the time the patient reaches middle age. There is an association of a specific gene called HLA B27. This in particular is in the type of psoriasis 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 affect primarily the joints involving the toes and the 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 typical nail changes in the hands and the feet which help the physician to make a diagnosis. The condition can be very painful, cause severe damage of the joints if not treated early enough and result in crippling disabilities.

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 is in its own way a diagnostic feature because in conditions such as rheumatoid arthritis one will usually have positive blood tests that support the diagnosis of rheumatoid arthritis.

The joints that are involved in the hands are usually the ones closest to the nail bed, the distal interphalangeal joint as opposed to the findings in rheumatoid arthritis where you may well have more involvement of the joints further away from the nail bed. In both conditions, the distribution of the disease can be called “bilateral and symmetrical”, in other words, affecting both hands in almost a mirror image like fashion. The condition is often aggravated by stress and worsens in the presence of other co-existing diseases.

It is critical to make an early diagnosis and start conventional treatment using the so-called nonsteroidal antiinflammatory drugs. The use of these drugs still forms a basis for the reduction in pain that is required. The nonsteroidals that one would use today are the Cox-2 specific group of anti-inflammatories, which have fewer side effects than the older traditional nonsteroidal antiinflammatory drugs.

Unfortunately, these drugs do nothing to affect the course of the disease, nor do they reverse the disease. In order to do this we have used other medications. In particular, for many years we have used Methotrexate, which is a drug used for rheumatoid arthritis predominately and types of cancer. This drug in low doses does help both the skin and the joint disease in psoriatic arthritis. Careful monitoring of the patient during use of Methotrexate is needed to prevent unexpected side effects especially on the liver.

Recently, a tremendous exciting breakthrough has introduced the use of biologic anti-TNF Alpha Blocking drugs. This new group of drugs is revolutionizing the treatment of arthritis. In this category in particular, we have Enbrel, which already has been approved for psoriatic arthritis.

Remicade and Humira which are about to be approved and are currently being used in clinical research studies in our office are showing outstanding results. The use of these three drugs has allowed 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.

At this point in time I believe psoriatic arthritis is a condition that should be treated early and intensively. But it is never too late to begin therapy. We are currently conducting a clinical trial for psoriatic arthritis in our office. If you would like more information or have any questions, please don’t hesitate to call our office for an evaluation and suggestions.