#12 Serum cystatin C: a novel biomarker for CKD detection—a meta-analysis

Abstract Background and Aims Chronic kidney disease (CKD) is a major public health concern. Early and accurate diagnosis is crucial for effective management and improved patient outcomes. Serum cystatin C has been proposed as a promising biomarker for CKD, offering advantages over traditional serum creatinine-based methods. This meta-analysis aims to evaluate the diagnostic accuracy of serum cystatin C for detecting CKD. Method A comprehensive literature search was conducted in public databases, including PubMed, Scopus, Cochrane, Embase, and Web of Science. Studies focusing on the sensitivity, specificity, and diagnostic odds ratio (DOR) of serum cystatin C in diagnosing CKD were included. Data were extracted and analyzed using a random-effects model. Heterogeneity was assessed and explored through subgroup analyses and meta-regression. Results A total of 25 studies involving 18,000 participants were included in this meta-analysis. The pooled sensitivity of serum cystatin C for diagnosing CKD was 88% (95% CI: 85–91%), and the specificity was 90% (95% CI: 87–92%). The diagnostic odds ratio was 50 (95% CI: 35–70), indicating high diagnostic accuracy. The area under the summary receiver operating characteristic (SROC) curve was 0.94 (95% CI: 0.92–0.96), confirming the robust diagnostic performance of serum cystatin C. For diabetic patients with CKD, the DOR was 60 (95% CI: 30–120), with sensitivity and specificity of 90% and 89%, respectively. Subgroup analysis revealed that serum cystatin C exhibited better diagnostic value in Western populations compared to Asian populations. Additionally, diagnostic accuracy was higher when serum cystatin C was measured using particle-enhanced nephelometric immunoassay (PENIA) compared to particle-enhanced turbidimetric immunoassay (PETIA). Conclusion This updated evidence, building on the last meta-analysis conducted in 2015, supports the high diagnostic accuracy of serum cystatin C for CKD. Its use as a diagnostic biomarker can facilitate early detection and management of CKD, ultimately improving patient outcomes.