Biopsy is commonly done when glomerular problems are likely, or when acute renal failure is unexplained.
Local anesthetic is used.
Examine glomeruli, tubules, and interstitium.
Look for areas devoid of tubules, suggesting scarring
PAS Stain demonstrates cellularity.
Silver staining..
IgA - can depict IgA nephropathy
IgG
Percutaneous biopsy is most commonly done and is relatively safe, though can lead to hematuria, hematoma, vascular lasceration and AV fistula formation, and biopsy of other tissues.