title: Limited diagnostic value of unilateral sacroiliitis in scintigraphy in assessing axial spondyloarthritis.
abstract: OBJECTIVE
  To assess the diagnostic value for axial spondyloarthritis (SpA) of unilateral sacroiliitis in scintigraphy in daily clinical practice.
  
  
  METHODS
  In 207 patients with chronic back pain, the diagnostic value of scintigraphy was assessed retrospectively. The diagnosis made by the rheumatologist (axial SpA vs no axial SpA) was the standard.
  
  
  RESULTS
  Sensitivities of scintigraphy for any (unilateral or bilateral), bilateral, and isolated unilateral sacroiliitis were 64.9%, 40.2%, and 24.7%, respectively. Respective specificities were 50.5%, 57.7%, and 92.8%, resulting in likelihood ratios of 1.3, 1.0, and 3.4.
  
  
  CONCLUSIONS
  Scintigraphy of the sacroiliac joints is of limited value for the diagnosis of axial SpA. Unilateral compared to bilateral sacroiliitis is slightly superior, but is associated with a low sensitivity.
authors.affiliation: Charité Medical University, Campus Benjamin Franklin, Medical Clinic I, Rheumatology, Hindenburgdamm 30, 12200 Berlin, Germany.
authors.forename: In-Ho
authors.initials: IH
authors.lastname: Song
authors.forename: Henning
authors.initials: H
authors.lastname: Brandt
authors.forename: Martin
authors.initials: M
authors.lastname: Rudwaleit
authors.forename: Joachim
authors.initials: J
authors.lastname: Sieper
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D016013:Likelihood Functions; D017116:Low Back Pain / Q000000981:diagnostic imaging / Q000209:etiology; D008297:Male; D011237:Predictive Value of Tests; D011877:Radionuclide Imaging; D012189:Retrospective Studies; D012446:Sacroiliac Joint / Q000000981:diagnostic imaging* / Q000473:pathology; D013167:Spondylitis, Ankylosing / Q000150:complications / Q000000981:diagnostic imaging* / Q000473:pathology