Is HLA B27 determination useful in Reactive Arthritis?
A sufficient number of patients with ReA will not be HLA-B27-positive, thus rendering HLA-B27 determination a poor diagnostic test in screening patients for ReA, especially because 7% of the normal white population will be positive. Patients with ReA can usually be successfully diagnosed and managed without HLA-B27 determination. However, many rheumatologists find it useful to classify patients as having either “HLA-B27-associated” or “nonassociated” forms of ReA since HLA-B27 positivity correlates with an increase in disease severity, chronicity, and frequency of exacerbations as well as development of aortitis, uveitis, and spondylitis.
