Diagnostic accuracy of the Xpert MTB/RIF assay for bone and joint tuberculosis: A meta-analysis

Background This study aimed to evaluate the accuracy of the Xpert MTB/RIF assay for the diagnosis of bone and joint tuberculosis. Methods We searched databases from their inception to May 7,2019 for published articles and reviewed them to assess the accuracy of Xpert MTB/RIF with respect to a composite reference standard (CRS) and mycobacterial culture. Meta-analyses were performed using a bivariate random-effects model, and the sources of heterogeneity were assessed via subgroup analysis and meta-regression. Results Nineteen independent (9 prospective, 5 retrospective, and 5 case-control) studies that compared Xpert MTB/RIF with the CRS and 14 (6 prospective, 7 retrospective, and 1 case-control) studies that compared it with culture were included. The pooled sensitivity and specificity of Xpert MTB/RIF were 81% (95% confidence interval [CI], 77-84) and 99% (95% CI, 97-100) compared to the CRS, respectively, and 96% (95% CI, 90-98) and 85% (95% CI, 57-96) compared to culture, respectively. The pooled sensitivity and specificity using pus samples vs. the CRS were 82% (95% CI, 76-86) and 99% (95% CI, 95-100), respectively. The proportions obtained while working with tissue samples vs. the CRS were 84% (95% CI, 76-90) and 98% (95% CI, 94-99), respectively. There was no significant difference in diagnostic accuracy among the types of specimens. Conclusions Xpert MTB/RIF demonstrates good diagnostic accuracy for bone and joint tuberculosis, the results of which are not related to the type of specimen.