title: Renal Biopsy in 2015--From Epidemiology to Evidence-Based Indications.
abstract: BACKGROUND
  Although the number of patients reaching end-stage kidney disease without a biopsy-proven diagnosis is increasing, the utility of renal biopsy is still an object of debate. We analyzed epidemiological data and the main indications for renal biopsy with a systematic, evidence-based review at current literature.
  
  
  CONCLUSIONS
  There is a high discrepancy observed in biopsy rates and in the epidemiology of glomerular diseases worldwide, related to the different time frame of the analyzed reports, lack of data collection, the different reference source population and the heterogeneity of indications. The evidence-based analysis of indications showed that renal biopsy should be crucial in adults with nephrotic syndrome or urinary abnormalities as coexistent hematuria and proteinuria and in corticosteroid resistant-children with severe proteinuria. The knowledge of renal histology can change the clinical management in patients with acute kidney injury significantly, after the exclusion of pre-renal or obstructive causes of kidney damage. Scarce evidence indicates that renal biopsy can be useful in patients with advanced chronic kidney disease and its use should always be considered after weighing the benefits and potential risks. Renal biopsy should be crucial in patients with renal involvement due to systemic disease. In patients with diabetes with atypical features, renal biopsy may be fundamental to diagnose an unexpected parenchymal disease mislabeled as diabetic nephropathy. Finally, in elderly patients, the indications and the risks are not different from those in the general population.
  
  
  CONCLUSIONS
  Renal biopsy still remains a concrete approach for managing a substantial percentage of renal diseases.
authors: Department of Emergency and Organ Transplantation, Nephrology, Dialysis and Transplantation Unit, University of Bari, Bari, Italy.
authors: Marco
authors: M
authors: Fiorentino
authors: Davide
authors: D
authors: Bolignano
authors: Vladimir
authors: V
authors: Tesar
authors: Anna
authors: A
authors: Pisano
authors: Wim
authors: W
authors: Van Biesen
authors: Graziella
authors: G
authors: D'Arrigo
authors: Giovanni
authors: G
authors: Tripepi
authors: Loreto
authors: L
authors: Gesualdo
mesh_terms: D001706:Biopsy; D019317:Evidence-Based Medicine; D006417:Hematuria / Q000473:pathology; D006801:Humans; D015994:Incidence; D007668:Kidney / Q000473:pathology*; D015995:Prevalence; D011507:Proteinuria / Q000473:pathology; D051436:Renal Insufficiency, Chronic / Q000453:epidemiology* / Q000473:pathology*