Ankylosing spondylitis: the challenge of early diagnosis.

Ankylosing spondylitis can present a difficult diagnostic challenge. Not only is its etiology unknown, but its clinical manifestations are myriad and sometimes precede classic low back pain by years. The foremost aid in diagnosis is an awareness of these manifestations, coupled with a willingness to make a tentative (possible or probable) diagnosis of the disease. HLA-B27 positivity and radiologic evidence of sacroiliitis cannot be considered more than nonspecific findings. The earlier the diagnosis, the earlier therapy can be instituted to prevent or minimize disabling deformities. Patient education is integral to therapy and should stress proper posture and exercise in addition to realistic expectations. Medication, particularly the nonsteroidal antiinflammatory drugs, to relieve pain and timely surgical intervention, such as total hip replacement, to relieve pain and/or improve function may also be necessary.