Novel CUBN Gene Mutations of an adolescentwith nephrotic syndrome, A Case Report and Review of the Literature
Mutations in the cubilin (CUBN) gene commonly cause Imerslund-Grasbeck syndrome, accompanied with isolated non-nephrotic range proteinuria. The renal biopsy findings are mainly minimal, non-specific, or absent. However, we identified one patient with massiveproteinuria triggered by compound heterozygous CUBN mutations. The renal biopsy demonstrated alterations in podocytes and the basement membrane, with deposition of immunoglobulin A (IgA) along the mesangial region. The identification of three novel mutation sites has expanded the spectrum of renal manifestations and the genotypic spectrum of CUBN variations. This is the first reported case of IgA nephropathy in an adolescent with novel CUBN mutations. We provide an extensive analysis of the etiology, pathogenesis, clinical manifestations, and treatment options to offer guidance for clinical management.