The Diagnostic Utility of Ki-67 Staining in Acute Renal Tubular Injury
Cynthia X Zhao, Xin Gu, Stephen M Bonsib. Louisiana State University Health Science Center, Shreveport, LA; Nephropath, Little Rock, AR
Background: Acute tubular injury (ATI) is one of the most common structural changes that can lead to acute renal failure. However, renal histological abnormalities are often subtle and may not be detectable. A reliable marker is needed to support the clinical findings of ATI. Ki-67 is a nuclear non-histone protein expressed in all phases of active proliferating cells. Renal tubular cell proliferation is increased following ATI. Thus, we hypothesize to use Ki-67 proliferation index (percentage of proliferating cells) to aid the diagnosis of ATI.
Design: Twenty kidney biopsies with the diagnosis of ATI and 20 kidney biopsies with no light microscopic tubular injury or glomerular abnormalities (18 thin basement membrane disease and 2 minimal change disease) were retrospectively selected. Ki-67 stain was performed on all 40 cases and the proliferation indices were calculated to evaluate tubular epithelial cell proliferative activities. Two-proportion Z-test was utilized to test the statistical significance between the two groups.
|Marked Increased (>10/HPF)||Increased (5-10/HPF)||Rare (<5/HPF)||Negative|