Abstract: PO2130
Chronic Active Antibody-Mediated Rejection: Response Rates to Treatment and Predictors of Graft Survival
Session Information
- Transplantation: Clinical - Underrecognized Risk Factors, Traditional Considerations, and Outcomes
November 04, 2021 | Location: On-Demand, Virtual Only
Abstract Time: 10:00 AM - 12:00 PM
Category: Transplantation
- 1902 Transplantation: Clinical
Authors
- Aziz, Fahad, University of Wisconsin System, Madison, Wisconsin, United States
- Parajuli, Sandesh, University of Wisconsin System, Madison, Wisconsin, United States
- Garg, Neetika, University of Wisconsin System, Madison, Wisconsin, United States
- Mohamed, Maha A., University of Wisconsin System, Madison, Wisconsin, United States
- Mandelbrot, Didier A., University of Wisconsin System, Madison, Wisconsin, United States
- Djamali, Arjang, University of Wisconsin System, Madison, Wisconsin, United States
Background
There is limited information on response rates to Rx and predictors of graft survival following chronic active antibody mediated rejection (cABMR).
Methods
We reviewed changes in kidney function, DSA, and histology in 3-month surveillance biopsies after initial therapy with pulse steroids/IVIG ± rituximab in kidney transplant recipients with cABMR between 01/2017 and 08/2020. Rx response was defined as 3M eGFR within 10% of baseline, proteinuria (UPC) decline by > 15%, DSA decline by > 50%, and MVI (ptc + g) score = 0.
Results
The study included 82 patients. 50% received rituximab. Mean time from Tx to cABMR was 10 yrs. Mean ptc, g, C4d, and cg Banff scores at index biopsy were 1.1, 2.1, 0.2, and 2, respectively. 47 patients (57%) had measurable circulating DSA. Mean eGFR and UPC were 38 mL/min and 1.6 g/g. Thirty (37%) patients lost their allograft during the mean follow-up of 2.4 yrs. At 3M, Rx with pulse steroids/IVIG was associated with eGFR, UPC, DSA, and MVI response in 27%, 49%, 7%, and 19% of patients. The addition of rituximab improved response to 66%, 61%, 20%, and 69%, respectively. On univariate analysis, rituximab use (HR=0.13, p=0.0001, 95%Cl 0.05 to 0.34) and a response in eGFR (HR=0.03, p=0.001, 95% Cl 0.004 to 0.26), UPC (HR=0.38, p=0.01, 95%Cl 0.18 to 0.82), and DSA (HR=0.11, p=0.004, 95%Cl 0.02 to 0.49) were associated with improved death-censored graft survival. Multivariate analysis only retained eGFR response (HR=0.12, p=0.01, 95%Cl 0.02 to 0.64).
Conclusion
Our study suggests that a return to baseline eGFR at 3M after initial biopsy is the best predictor of graft survival in patients with cABMR. Short-term histological and immunological response to treatment were not independently associated with graft survival.
Response Rate at Surveillance Biopsy
| Response | Steroids/IVIG | Steroids/IVIG/Rituximab | p-value | |
| eGFR | 11/41 (27%) | 27/41 (66%) | 0.004 | |
| UPC | 20/41 (49%) | 25/41 (61%) | 0.3 | |
| DSA | 4/21 (19%) | 18/26 (69%) | 0.007 |