The Heartbreak of Psoriasis - And Other Worries

People often complain about arthritis as if it were one disease. Untrue. Arthritis is a term used to describe more than 100 different conditions involving joint disease.

Some diseases are relatively mild. Others can be quite serious, involving other organ systems, and leading to potential disability as well as the possibility of a shortened life span.

One disease that is not well understood by both the general public as well as many physicians is psoriatic arthritis. This is the form of arthritis that often accompanies psoriasis, an autoimmune skin disease.

Psoriatic arthritis (PsA) is not rare. According to one study (Gelfand J, et al. J AM Acad Dermatol 2005; 534: 573-577), as estimated 520,000 people in the United States have the condition.

It is not an easy disease to diagnose because it may present in a dizzying array of fashions.

The primary symptoms of PsA are joint pain and stiffness. However, other modes of presentation are almost as common. These include enthesitis (inflammation where tendons joint bones), dactylitis (swelling of a finger or toe so that it looks like a "sausage"), and skin psoriasis.

Enthesitis causes inflammation where tendons or ligaments attach to bone. Common sites for symptoms to occur are the Achilles tendon, the plantar fascia (bottom of the heel), medial knee, patellar tendon, (where the patellar tendon inserts into the patella), iliac crest, triceps tendon, and lateral epicondyle. In essence, enthesitis can occur at pretty much any point where a tendon, ligament or even joint attaches to bone.

Approximately, 30 per cent of patients with PsA have enthesitis. Because the symptoms can be widespread and vague and not confined to joints, the clinical picture can be confusing. Other conditions associated with widespread pain such as fibromyalgia may be considered in the list of diagnostic possibilities. The isolated presentation of what appears to be typical plantar fasciitis may be a sign of PsA.

The other symptom that is classic is dactylitis- the "sausage digit." The sausage appearance is due to inflammation of the tendon sheath in the finger or toe. Dactylitis also occurs in about 30 per cent of patients.

The importance of dactylitis is that it is a good indicator of disease severity. It also tells the doctor that the disease is active and not well-controlled. Dactylitis is also a harbinger of severe disease that can ultimately lead to joint destruction.

Fortunately, there are medications which are extremely effective in controlling PsA. A combination of disease-modifying anti-rheumatic drugs (DMARDS) and biologics usually results in excellent disease control and remission.