Renal biopsy

Most acute renal failure is due to pre-renal causes or acute tubular necrosis, and recovery of renal function typically occurs over the course of a few weeks.

Renal biopsy should be performed only if knowing histology will influence management.

Once chronic renal failure is established, the kidneys are small, there is a higher risk of bleeding from biopsy, and the results are usually unhelpful.