The diagnostic value of scintigraphy in assessing sacroiliitis in Ankylosing Spondylitis - a systematic literature research
- IH Song ( )
- M Rudwaleit ( )
- J Sieper ( )
- Published Online First 29 January 2008
Background: The diagnostic value of scintigraphy in detecting sacroiliitis in patients with spondyloarthritis is not clear.
Objective: To assess the diagnostic value of scintigraphy in detecting sacroiliitis in ankylosing spondylitis (AS) and in patients with clinically probable sacroiliitis without x-ray changes. Material and methods: A systematic literature research was performed in the pubmed and medline database up to August 2007. Articles in English and German on patients with established AS and clinically probable sacroiliitis without x-ray changes were selected. In addition, studies including patients with mechanical low back pain (MLBP) as a control group were searched. Pooled sensitivity, specificity and positive and negative likelihood ratios (LRs) were calculated.
Results: In total 99 articles about scintigraphy were found. 25 articles were included into the analysis. Overall sensitivity for scintigraphy to detect sacroiliitis was 51.8% for patients with established AS (N= 361) and 49.4% for patients with probable sacroiliitis (N= 255). Sensitivity of scintigraphy in AS patients with inflammatory back pain (indicating ongoing inflammation) was 52.7% (N= 112) and in patients with AS and suspected sacroiliitis with magnetic resonance imaging showing acute sacroiliitis (as a gold standard) was 53.2% (N= 62). In controls with MLBP specificity was 78.3% (N= 60) resulting in LRs not higher than 2.5-3.0.
Conclusion: These data as a result of a literature research suggest that scintigraphy of the sacroiliac joints is at the most of limited diagnostic value for the diagnosis of established AS including the early diagnosis of probable / suspected sacroiliitis.