Table 2.

Comparison of biopsies from discarded and paired control kidneys from the same donor

Biopsy CharacteristicKidney Discarded
for Biopsy Findings (n=83)Contralateral Kidney
Not Discarded (n=83)P Valuea
Wedge (versus needle)42/63 (66.7)47/63 (74.6)0.10
Frozen tissue (versus paraffin-embedded tissue)49/50 (98.0)49/50 (98.0)NE
Number of glomeruli assessed53.5±40.955.2±39.80.50
Percentage of global sclerosis17.1±15.39.0±6.6<0.001
Percentage of global sclerosis >20%27/83 (32.5)4/83 (4.8)<0.001
Biopsy findings, if reportedb
 Tubular atrophy (52 pairs)1.00±0.560.87±0.490.08
 Interstitial fibrosis (80 pairs)0.95±0.550.78±0.570.01
 Interstitial inflammation (37 pairs)0.81±0.570.65±0.540.07
 Vascular damage (75 pairs)1.01±0.730.87±0.620.04
 Arteriolar hyalinosis (35 pairs)0.63±0.600.69±0.72NE
 Acute tubular necrosis (32 pairs)0.72±0.810.69±0.640.85
Missing biopsy information
 Wedge versus needle biopsy18/83 (21.7)17/83 (20.5)0.66
 Tissue processing method not indicated29/83 (34.9)32/83 (38.6)0.22
 Tubular atrophy27/83 (32.5)29/83 (34.9)0.42
 Interstitial fibrosis2/83 (2.4)3/83 (3.6)NE
 Interstitial inflammation43/83 (51.8)39/83 (47.0)0.22
 Vascular damage6/83 (7.2)8/83 (9.6)NE
 Arteriolar hyalinosis44/83 (53.0)44/83 (53.0)1.00
 Acute tubular necrosis47/83 (56.6)50/83 (60.2)0.22
  • Data are presented as the fraction (%) or mean±SD. NE, not estimable due to too few discordant pairings.

  • a P values for binary data were generated from logistic regression for repeated measures using generalized estimating equations and taking into account the nested correlation induced by kidney laterality within donor (5). P values for parametric data were generated from a signed rank test on the matched case-control differences for clustered data (6). See Supplemental Table 2 for details.

  • b 0, none; 1, mild; 2, moderate; 3, severe.