Kidney Week

Abstract: PO2268

Standardized Grading of Chronicity in Native Renal Biopsies: A Single-Center Experience

Session Information

• Pathology and Lab Medicine: Clinical
  October 22, 2020 | Location: On-Demand
  Abstract Time: 10:00 AM - 12:00 PM

Category: Pathology and Lab Medicine

• 1602 Pathology and Lab Medicine: Clinical

Authors

• Huang, Yuan, University of Cincinnati, Cincinnati, Ohio, United States

Yuan Huang,

• Lee, Paul J., University of Cincinnati, Cincinnati, Ohio, United States

Paul J. Lee,

• Wang, Diping, University of Cincinnati, Cincinnati, Ohio, United States

Diping Wang,

Background

Chronic changes in native kidney biopsies are important in predicting prognosis and guiding treatment. In this retrospective single-center study, we investigated the applicability of histological chronicity grading in native kidney biopsies, using a newly proposed standardized grading system by Sethi et. al. and with modifications.

Methods

52 consecutive patients (46.8 ± 16.1 yrs, 53.8% F) from January 2017 to December 2019 were recruited and 44 cases were deemed adequate. 9 categories of histopathology were evaluated and scored independently and blindly by two renal pathologists. An accumulated score (Sum1) was obtained from 4 categories the paper proposed. The other 5 categories were included to provide additional histopathologic information, which generated Sum2 score (Figure). Interrater agreement was measured by kappa statistics. eGFR levels both at the time of biopsy and at the end of 12 to 18-month follow-up were obtained from electronic medical records. The correlations between the calculated total scores and continuous variables were determined by bivariate correlation analysis.

Results

Interrater agreement was almost perfect based on the Landis and Koch scale with a kappa value 0.89. Among the 44 analyzed cases, mean baseline eGFR was 39.6 ± 29.7 mL/min/1.73m² . At the end of follow-up, eGFR was 47.8 ± 29.3 mL/min/1.73m². Sum1 and Sum2 scores were significantly correlated with both baseline eGFR levels (R=-0.34, p<0.05, and R=-0.44, p<0.01, respectively) and those at the end of follow-up (R=-0.56, p<0.01 and R=-0.44, p<0.01, respectively).

Conclusion

We demonstrated that the modified criteria were comparable to the original criteria; both had good interrater agreement and correlated well with eGFR levels. The modified criteria could provide standardized grading of additional clinically relevant histopathology. Application of standardized chronicity grading will benefit prognosis evaluation and clinical management of renal diseases.

Funding

• Clinical Revenue Support