Diagnostic accuracy of fluorine-18 fluorodeoxyglucose positron emission tomography for suspected primary and postoperative pyogenic spondylitis

Abstract

Objective Fluorine-18 fluorodeoxyglucose positron emission tomography (18F-FDG PET) and PET/CT have been suggested for confirming or excluding musculoskeletal infection but the diagnostic value of this tool for pyogenic spondylitis remains to be confirmed. This meta-analysis was performed to verify the accuracy of 18F-FDG PET and PET/CT in diagnosing suspected pyogenic spondylitis by performing a systematic review and meta-analysis. Methods We conducted a comprehensive literature search of PubMed, Embase and Cochrane Library to retrieve diagnostic accuracy studies in which suspected pyogenic spondylitis was assessed with 18F-FDG PET or PET/CT. The pooled sensitivity, specificity, likelihood ratios, diagnostic odds ratio (DOR), summarized receiver operating characteristic curve (sROC) and the area under the sROC (AUC) were calculated by using Stata software. Results A total of 18 eligible studies (660 patients) with suspected pyogenic spondylitis were included in the quantitative analysis. 18F-FDG PET and PET/CT illustrated relatively high sensitivity (0.91, 95% CI: 0.84–0.95) and specificity (0.90, 95% CI: 0.79–0.95) for the diagnosis of pyogenic spondylitis. The pooled DOR and AUC were 86.00 (95% CI, 31.00–240.00) and 0.96 (95% CI, 0.94–0.97), respectively. For diagnosing pyogenic spondylitis without previous spine surgery, the pooled sensitivity, specificity, DOR and AUC were 0.93 (95% CI, 0.85–0.97), 0.91 (95% CI, 0.77–0.97), 136 (95% CI, 35–530) and 0.97 (95% CI, 0.95–0.98), respectively. For diagnosing postoperative pyogenic spondylitis, the pooled sensitivity, specificity, DOR and AUC were 0.85 (95% CI, 0.71 to 0.93), 0.87 (95% CI, 0.66 to 0.96), 38 (95% CI, 9 to 167) and 0.92 (95% CI, 0.89 to 0.94), respectively. Conclusion 18F-FDG PET and PET/CT presented satisfactory accuracy for diagnosing pyogenic spondylitis. The diagnostic effect of this nuclear imaging method for pyogenic spondylitis without previous spine surgery seems to be better than that for the postoperative ones. However, whether 18F-FDG PET and PET/CT could become a routine in patients with suspected pyogenic spondylitis remains to be confirmed. Level of evidence Level I evidence, a summary of meta-analysis.