Evaluation for joint disease now part and parcel of psoriasis patient care

Dermatologists have the opportunity to make an early diagnosis of psoriatic arthritis, and so it is incumbent upon them to be evaluating all psoriasis patients for signs and symptoms of joint disease, says Craig L. Leonardi, M.D.

"Seventy percent of patients with psoriatic arthritis present initially with skin disease and another 15 percent develop skin and joint symptoms in the same year. Looking for joint disease in psoriasis patients was not part of my training in dermatology almost 20 years ago, but the standard of care is shifting and I believe it is now our obligation," says Dr. Leonardi, associate clinical professor of dermatology, St. Louis University, St. Louis.

Patients with psoriatic arthritis will present with plaque psoriasis and often have nail lesions as well as simultaneous flaring of skin disease and joint symptoms. The physical exam should look for signs of joint disease, particularly distal interphalangeal joint involvement and swelling of the fingers.

Questions to ask to identify early or emerging psoriatic arthritis should aim to elicit problems with stiffness in the morning or following other prolonged periods of inactivity, such as after a long car ride, as well as the presence of inflammatory pain in the neck or back.

When a biologic is being used to treat psoriasis and the patient also has psoriatic arthritis, dermatologists should be aware those agents differ dramatically in their efficacy for treating joint disease.

"Efalizumab (Raptiva) failed in a phase 2 trial of psoriatic arthritis and while alefacept (Amevive) achieved positive results, I doubt it would be a first-line choice of any rheumatologist. Adalimumab (Humira), infliximab (Remicade) and etanercept (Enbrel) appear to be similar when outcomes are analyzed using percentage of ACR20 and ACR50 responders as the endpoint. However, using the more stringent ACR70 response rate, adalimumab and infliximab clearly outperform etanercept," he says.