musculoskeletal and connective tissue disorders
Psoriatic Arthritis
Symptoms and Signs of Psoriatic Arthritis
Psoriasis of the skin or nails may precede or follow joint involvement. Severity of the joint and skin disease is often discordant. Also, skin lesions may be hidden in the scalp, ears, gluteal folds, or umbilicus and go unrecognized by the patient. Peripheral psoriatic arthritis may involve small, medium, and large joints with a high tendency to affect distal interphalangeal joints of fingers and toes. It may manifest in different patterns such as asymmetric oligoarthritis, symmetric polyarthritis (which can be confused with rheumatoid arthritis), and arthritis mutilans that is characterized by rapid destructive arthritis with telescoping of the digits. Joint and skin symptoms may lessen or worsen simultaneously. Inflammation of the flexor tendons of fingers, toes, or both may lead to sausage-shaped deformities (dactylitis), which are not present in patients with Rheumatoid Arthritis (RA) . Rheumatoid nodules are absent. Arthritic remissions tend to be more frequent, rapid, and complete than in rheumatoid arthritis, but progression to chronic arthritis and crippling may occur. Enthesopathy (inflammation at tendinous insertion into bone—eg, Achilles tendinitis, patellar tendinitis, elbow epicondyles, spinous processes of the vertebrae) can develop and cause pain and swelling. Axial involvement may be present, especially in male patients with positive HLA-B27, and usually manifests as asymmetric involvement of the sacroiliac joints. This image shows swelling of right fourth distal interphalangeal joint in a patient with psoriatic arthritis. Image courtesy of Kinanah Yaseen, MD. This photo shows sausage-shaped deformities (dactylitis) of the fingers in a patient with psoriatic arthritis. Also apparent are pitting of the nails and salmon patches on the skin. © Springer Science+Business Media This photo shows red, flaky, and thickened skin on the scalp of a patient with psoriasis. DR P. MARAZZI/SCIENCE PHOTO LIBRARY This photo shows erythematous plaques covered with silvery-white scales on the extensor surface of the elbows. This appearance is typical of plaque psoriasis. SCIENCE PHOTO LIBRARY 