Psoriatic arthritis: clinical spectrum and diagnostic procedures.

Psoriatic arthritis presents with a broad clinical spectrum of symptoms. Symmetrical polyarthritis with joint pain and joint swelling is one pattern of clinical manifestations that often indicates erosive progressive disease. Unlike in rheumatoid arthritis, the distal interphalangeal joints are regularly involved. Sometimes, the disease focuses on the larger joints of the lower extremities; iliosacral and intervertebral joints and tendons can also be involved. Thus, inflammatory back pain as well as any other prolonged joint pain in a patient with psoriasis is suspicious of psoriatic arthritis. This article reviews the clinical spectrum and diagnostic procedures that can lead to the diagnosis of psoriatic arthritis.