Ultrasonographic evaluation of lower limb enthesis in patients with early spondyloarthropathies

The enthesopathy of seronegative spondyloarthropathies (SpA) is the hallmark of these diseases, the ultrasound examination of these entheses confirms the frequency of their involvement. To detect entheseal abnormalities with ultrasound (US) in the lower limb of patients with early spondyloarthropathy (SpA) and to evaluate US as a valuable tool in detecting early enthesis. A total of 45 patients with early disease duration of 11.7 ± 8.5 months, including 10 patients with psoriatic arthritis (PsA), 10 patients with ankylosing spondylitis (AS), 10 patients with reactive arthritis (ReA), eight patients with ulcerative colitis (UC) and seven patients with Crohn’s disease and 20 healthy controls of matched age and sex underwent ultrasonographic evaluation of Achilles, quadriceps, patellar entheses and plantar aponeurosis. Ultrasonographic findings were scored according to the Glasgow Ultrasound Enthesitis Scoring System (GUESS). On US examination a total of 290/450 (64.4%) of the entheseal sites were abnormal. Mean GUESS score was significantly higher in patients with SpA as compared with controls (p < 0.001), with a higher mean value in patients with PsA, ReA and AS. The mean thickness of all tendons examined was significantly higher in SpA patients than in controls (p < 0.0001) as well as the mean number of enthesophytes and bursitis in all sites examined (p = 0.002, p = 0.003), with a higher prevalence amongst patients with PsA and ReA. The GUESS score was correlated to duration of the disease and the anti-tumour necrosis factor alpha medications. Enthesis involvement occurs early in spondyloarthritis, the enthesis US score appears to be reliable and useful for improving the diagnostic accuracy of early SpA, further studies are needed as US is an evolving technique.