Culture yield of repeat percutaneous image-guided biopsy after a negative initial biopsy in suspected spondylodiscitis: a systematic review

OBJECTIVE: To systematically review the published data on the culture yield of a repeat (second) percutaneous image-guided biopsy after negative initial biopsy in suspected spondylodiscitis. MATERIALS AND METHODS: A systematic search was performed of the PubMed/Medline and Embase databases. The methodological quality of the studies included was assessed. The proportions of positive cultures among all initial biopsies and second biopsies (after a negative initial biopsy) were calculated for each study and assessed for heterogeneity (defined as I(2) > 50%). RESULTS: Eight studies, comprising a total of 107 patients who underwent a second percutaneous image-guided biopsy after a culture-negative initial biopsy in suspected spondylodiscitis, were included. All eight studies were at risk of bias and were concerning with regard to applicability, particularly patient selection, flow of patients through the study, and timing of the biopsy. The proportions of positive cultures among all initial biopsies ranged from 10.3 to 52.5%, and were subject to heterogeneity (I(2) = 73.7%). The proportions of positive cultures among all second biopsies after negative initial biopsy ranged from 0 to 60.0%, and were not subject to heterogeneity (I(2) = 38.7%). CONCLUSION: Although a second percutaneous image-guided biopsy may have some value in patients with suspected spondylodiscitis, its exact value remains unclear, given the available poor-quality evidence. Future well-designed studies are needed to determine the role of a second percutaneous image-guided biopsy in this setting. Such studies should clearly describe the spectrum of patients that was selected for a second percutaneous image-guided biopsy, the method of biopsy, and differences compared with the first biopsy, if any.