[1366] Inter-Observer Agreement between Surgical and Renal Pathologist on Interpretation of Renal Donor Biopsies for Transplant Suitability

M Cox, C Pennington, SG Sharma, HJ Spencer, N Gokden. University of Arkansas for Medical Sciences, Little Rock, AR

Background: Microscopic evaluation of donor kidney biopsies is required to determine donor kidney suitability for transplant in selected cases. In our institution, frozen section interpretations are performed routinely by the surgical pathologist on call. Most specimens are wedge biopsies. After the tissue is snap-frozen, two hematoxylin and eosin-stained frozen sections are evaluated. To our knowledge, there are no data on inter-observer agreement between surgical pathologist (SP) and renal pathologist (RP) on interpretation of kidney donor biopsies.
Design: Retrospectively, 60 kidney donor wedge biopsies were retrieved from surgical pathology files in our institution and were reviewed by a renal pathologist (NG). The percent ratios (%) of glomeruli with global sclerosis, glomeruli and arterioles with fibrin thrombi, acute tubular necrosis (ATN), interstitial inflammation and fibrosis, the amount of arterial and arteriolar intimal fibrosis, and the presence/absence and extent of cortical necrosis were tabulated for each case. Results were compared with original reports signed out by ten different SP and kappa statistics were used to assess inter-observer agreement. P values less than 0.05 were considered statistically significant.
Results: Inter-observer agreement on interpretation of donor kidney biopsy by SP and RP was between moderate and substantial agreement with kappa values ranging between 0.42 and 0.71. The agreement was moderate for % glomeruli with thrombi (=0.48; p= 0.03), % of ATN (=0.46; p<0.001), % of interstitial fibrosis (=0.43; p=0.003) and the amount of arteriolar intimal fibrosis (=0.49; p=0.003). Substantial agreement was observed for % of globally sclerosed glomeruli (=0.70; p<0.001), % of interstitial inflammation (=0.63; p<0.001), and the amount of arterial intimal fibrosis (=0.72; p<0.001).
Conclusions: Our data show that SP as a group provide similar interpretations as RP on donor kidney biopsies for transplant suitability.
Category: Kidney (does not include tumors)

Tuesday, March 10, 2009 1:00 PM

Poster Session IV # 181, Tuesday Afternoon