Spondyloarthropathies: Using Presentation to Make the Diagnosis

Spondyloarthropathy is a family of arthritides that includes:

•Ankylosing spondylitis

•Reactive arthritis (including Reiter syndrome)

•Psoriatic arthritis

•Enteropathic spondyloarthropathy (ie, spondyloarthropathy associated with inflammatory bowel disease)

•Undifferentiated spondyloarthropathy (forms that fail to meet the clinical criteria for the other categories).(1)

The spondyloarthropathies are linked by association with the class 1 human leukocyte antigen (HLA)-B27 and by a common clinicopathologic lesion-enthesitis.

There is no serologic test to aid in the diagnosis. Rather, the diagnosis is made by analyzing a constellation of factors, such as axial and peripheral joint and skeletal involvement, associated clinical features, and genetic predisposing factors.(2)

Treatment has been focused on the relief of symptoms with drugs such as nonsteroidal antiinflammatory drugs. The new tumor necrosis factor inhibitors may have a role in modifying the course of this family of conditions, but experience with these drugs is limited.

In this article, we review the clinical presentation of the spondyloarthropathies to help guide the clinician through diagnosis and treatment.

Epidemiology
An epidemiologic assessment of blood donors in Berlin, Germany,3 found that 1.9% had a spondyloarthropathy: 0.86% had ankylosing spondylitis, 0.67% had undifferentiated spondyloarthropathy, and 0.29% had psoriatic arthritis. Reactive arthritis and enteropathic spondylitis were much less common.(3)

The prevalence of spondyloarthropathy, particularly of ankylosing spondylitis, correlates most strongly with the prevalence of HLA-B27 in the general population. The percentage of spondyloarthropathy patients with this gene varies from about 90% in those with ankylosing spondylitis to 20% in those with psoriatic arthritis or undifferentiated spondyloarthropathy (Table 1).(4-9) Ankylosing spondylitis and reactive arthritis are more common in men, but are likely underdiagnosed in women. The mean age at diagnosis is generally in the 30s and 40s. Most people with the HLA-B27 gene do not develop ankylosing spondylitis. Table 1 (3-11) provides the key demographic characteristics of the spondyloarthropathies.

Table 1: Demographic Features of the Spondyloarthropathies

*Based on the European Spondyloarthropathy Study Group data from seven rheumatology centers, including 403 patients diagnosed with spondyloarthropathy.

Cleveland Clinic Journal of Medicine
Volume 71, Number 3, March 2004

This paper discusses therapies that are experimental or are not approved by the U.S. Food and Drug Administration for use under discussion.