Diagnostic accuracy of biomarkers for irritable bowel syndrome: a systematic review and meta-analysis

This study aimed to systematically assess the diagnostic performance of multiple biomarkers for irritable bowel syndrome (IBS). Systematic electronic searches were conducted in PubMed, Cochrane Central Register of Controlled Trials, Embase, and Web of Science, with the search updated through May 18, 2025. Studies were evaluated in accordance with the Diagnostic Test Accuracy systematic review manual and the PRISMA-DTA reporting guidelines. Methodological quality of included studies was assessed using the QUADAS-2 and QUADAS-C tools. We synthesized summary sensitivity and specificity using a bivariate random-effects model within a hierarchical summary receiver operating characteristic framework. Of 9,078 initially identified studies, 24 eligible studies involving 9,343 participants were ultimately included in the meta-analysis. Pooled analysis revealed that urinary metabolic markers exhibited high diagnostic accuracy, with a pooled sensitivity of 0.988 (95% CI: 0.804-1.000) and a pooled specificity of 0.934 (95% CI: 0.629-0.993). In biomarker-type subgroup analyses, fecal peptidase activity yielded a sensitivity of 0.905 (0.438-0.990) and specificity of 0.883 (0.513-0.978), while RAID-IBS showed a sensitivity of 0.935 (0.548-0.994) and specificity of 0.919 (0.444-0.986). When stratified by comparator groups, urinary metabolites exhibited a sensitivity of 0.981 (0.800-0.999) and specificity of 0.803 (0.271-0.981) against healthy controls, compared to a sensitivity of 0.995 (0.926-1.000) and specificity of 0.996 (0.944-1.000) against inflammatory bowel disease. These results suggest that urinary metabolites, fecal peptidase activity, and RAID-IBS may achieve high sensitivity and specificity in the studies available.