Verification of Berlin algorithm for diagnosing undifferentiated spondyloarthropathy patients in Chinese population

ObjectiveTo evaluate the diagnosing value of the Berlin algorithm, comparing to that of the established ESSG and Amor criteria in Chinese patients with undifferentiated spondyloarthropathy.MethodsA total of 92 clinically diagnosed undifferentiated spondyloarthropathy patients with axial involvement were compared to 123 patients with other kinds of rheumatic diseases by using the parameters listed in the Berlin algorithm, ESSG criteria, and Amor criteria.ResultsIn the 92 undifferentiated spondyloarthropathy patients with axial involvement, the prevalence rate of HLA-B27 was 71.76% (61/85). Elevated ESR and/or CRP was found in 40.96% (34/83) SpA patients and abnormal MRI manifestation of sacroiliac joint was found in 91% (39/43) SpA patients. The specificity of HLA-B27 was 78% and similar with the Berlin study. The sensitivity/specificity of ESSG, Amor criteria and Berlin algorithm on diagnosing USpA was 72.83%/92.68%, 64.13%/93.50% and 67.39%/95.93%, respectively. The coincidence between the three diagnosing criteria and the rheumatologist's opinion was moderate.ConclusionOur study showed the new Berlin algorithm has important value of diagnosing undifferentiated spondyloarthropathy in China, which has the similar diagnosing capacity comparing to the traditional criteria ESSG and Amor criteria.