Clinical Relevance of Xpert MRSA/SA in Guiding Therapeutic Decisions for Staphylococcal Infections: A Diagnostic Test Accuracy Analysis

Infect Dis Ther. 2022 Jun;11(3):1205-1227. doi: 10.1007/s40121-022-00632-w. Epub 2022 Apr 22.

Abstract

Introduction: Rapid identification of the causal organism and antibiotic resistance is crucial for guiding targeted therapy in patients with suspected staphylococcal infection. A meta-analysis was carried out to evaluate the diagnostic relevance of Xpert™ MRSA/SA (Xpert) from clinical samples of various origins for limiting the use of unnecessary empirical methicillin-resistant Staphylococcus aureus (MRSA) therapy.

Methods: Five databases, including the Cochrane Library, Scopus, PubMed, Web of Science, and Embase, were comprehensively inspected from inception to October 12, 2021. The pooled summary estimates were evaluated using a bivariate random-effects model.

Results: Our inclusion criteria were met by 49 publications containing 68 datasets out of 735 citations. A total of 21 studies (n = 4996) examined the accuracy of Xpert in detecting methicillin-sensitive S. aureus (MSSA), while 47 studies (n = 45,430) examined the accuracy of Xpert in detecting MRSA. As compared to MRSA, Xpert's diagnostic performance for MSSA detection was markedly higher [sensitivity: 0.97 (0.96-0.98), specificity: 0.97 (0.97-0.98), area under curve (AUC): 0.99 (0.99-1.0)]. Xpert's pooled sensitivity and specificity differed marginally across sample types, including screening of colonization, lower respiratory tract (LRT), osteoarticular, and bloodstream samples. Notably, the Xpert pooled specificity was consistently ≥ 92% against microbiological culture across all sample types. The diagnostic efficiency heterogeneity was not explained by a meta-regression and subgroup analysis of research design, sample conditions, and sampling methods (P > 0.05).

Conclusion: Our findings suggest that Xpert could be used as the favoured screening test for the early detection of staphylococcal infection in a variety of sample types, with the goal of guiding therapeutic decisions.

Keywords: Bacteremia; Osteoarticular infection; Respiratory infection; Staphylococcal infection; Xpert accuracy.