Glomerular C4d Deposition and Kidney Disease Progression in IgA Nephropathy: A Systematic Review and Meta-analysis
Yuanyuan Jiang, Jincan Zan, Sufang Shi, Wanyin Hou, Wenjing Zhao, Xuhui Zhong, Xujie Zhou, Jicheng Lv, Hong Zhang
Abstract
BACKGROUND: Glomerular deposition of C4d is a widely used biomarker for activation of the lectin pathway in the complement system and is reported to be associated with kidney progression in immunoglobulin A nephropathy (IgAN). The aim of this study was to evaluate whether glomerular C4d deposition, as a new biomarker, improves the prediction of kidney prognosis in IgAN. STUDY DESIGN: Systematic review and meta-analysis. SETTING & POPULATION: Patients with biopsy-proven primary IgAN without age limitations.Selection Criteria for Studies: Cross-sectional or cohort studies reporting the prevalence of glomerular C4d deposition or evaluating its association with IgAN progression. PREDICTOR: Glomerular C4d deposition. OUTCOME: Composite progression event of a >30% decline in estimated glomerular filtration rate or end-stage kidney disease. RESULTS: < 0.001) without evidence of heterogeneity. LIMITATIONS: The definition of positive C4d was not uniform and not all studies provided data about kidney outcomes. CONCLUSIONS: Glomerular C4d deposition is associated with an adverse prognosis and may be a useful biomarker of disease prediction in IgAN.