Fibronectin Glomerulopathy: A Case Report of Membranoproliferative Glomerulonephritis.

Background. Fibronectin glomerulopathy (FNG) is a rare autosomal dominant glomerulopathy characterized by proteinuria, hematuria, hypertension, and gradual progression to end-stage renal disease (ESRD) over 15-20 years. The disease is caused by mutations in the FN1 gene. Currently, there is no specific treatment for FNG. Case Report. A 22-year-old female presented with sub-nephrotic proteinuria and microscopic hematuria. Renal biopsy revealed mesangial expansion and electron-dense deposits consistent with FNG. Genetic testing confirmed a mutation in the FN1 gene (c.5773T>A, W1925R). No kidney disease was observed in patient's parents; later genetic diagnosis was confirmed also in the patient's brother. She was treated with conservative therapy. Three years later, her kidney function remained stable, with a serum creatinine of 0.5 mg/dL and proteinuria reduced to 0.7 g/24h. Discussion. FNG is caused by mutations in the FN1 gene, leading to abnormal fibronectin deposition in the kidneys. No specific treatment exists, but conservative therapy with ACE inhibitors may help slow disease progression. Steroid therapy is controversial, with limited success in preventing ESRD. Conclusion. Early diagnosis and conservative treatment are crucial for managing FNG. Further research is needed to explore effective therapies and better understand the disease's progression.