Fibronectin Glomerulopathy Without Typical Renal Biopsy Features in a 4-Year-Old Girl with Incidentally Discovered Proteinuria and a G417V Gene Mutation.

Fibronectin glomerulopathy (FG) is caused by fibronectin 1 () gene mutations. A renal biopsy was performed on a 4-year-old girl with incidentally discovered proteinuria (150 mg/dL); her family history of renal disease was negative. Markedly enlarged glomeruli (mean glomerular diameter: 196 μm; age-matched controls: 140 μm), α-SMA-positive and Ki-67-positive mesangial cell proliferation (glomerular proliferation index 1.

The Apical Endocytic-Lysosomal Apparatus in CLCN5 Mutations with Phenotypic-Genotypic Correlations in Three Cases.

Dent disease type 1 is characterized by pathogenic gene variants and impaired receptor-mediated endocytosis in proximal tubules. However, mutation-related abnormalities in proximal tubules have not yet been described. Here, we present three patients with CLCN5 alterations and distinct morphological changes of the apical endocytic-lysosomal apparatus.

Phenotype-Genotype Correlations in Three Different Cases of Adult-Onset Genetic Focal Segmental Glomerulosclerosis.

This study highlights the importance of a combined diagnostic approach in the diagnosis of rare diseases, such as adult-onset genetic FSGS. We present three adult patient cases evaluated with kidney biopsy for proteinuria, chronic kidney disease, and hypertension, which were suggestive of adult-onset genetic FSGS. Renal biopsy samples and formalin-fixed, paraffin-embedded fetal kidneys were evaluated using standard light microscopical stainings, direct immunofluorescence on cryostat sections, and electron microscopy.

[A rare tubulopathy: Dent's disease in the background of focal segmental glomerular sclerosis].

Dent's disease is a proximal tubulopathy with heterogeneous genetical background. The typical clinical finding is characterized by low molecular weight proteinuria, hypercalciuria, nephrocalcinosis/nephrolithiasis and progressive chronic kidney failure. The underlying cause of the disease is the genetic defect (most commonly CLCN5 mutation) of the receptor-mediated endocytosis in the structure of proximal tubules.