Renal Biopsy Unexplained Elevated Serum Creatinine

Renal biopsy samples will be obtained by a percutaneous method using a spring-loaded Trucut® biopsy needle under real time ultrasound guidance. Biopsy samples will be processed for light microscopy with special staining will be done: Schiff periodic acid, Masson trichrome and methenamine silver.and immunofluorescence studies to evaluate IgA, IgG, IgM, complement C1q and C3, fibrin, and kappa and lambda light chain deposits.