Treatment of chronic active T cell‐mediated rejection after kidney transplantation: A retrospective cohort study of 37 transplants

Aim Data on the treatment of chronic active T cell‐mediated rejection (CA‐TCMR) are scarce, and therapeutical strategies for CA‐TCMR have not been established. We retrospectively evaluated the outcomes and effects of treatment on pathological and clinical findings in patients with CA‐TCMR. Methods This study comprised 37 patients who underwent kidney transplantation at our institute who were diagnosed with CA‐TCMR between January 2018 and December 2020. Patients were followed until October 2021. Results A total of 32 of the 37 patients were treated. During the observation period, two patients died (5%), and five patients developed allograft loss (13%). A univariate Cox proportional hazards model showed that indication biopsy, higher spot urine protein/creatinine ratio (UPCR) and Banff ci/ct scores were risk factors for allograft loss. Of the treated patients, 23 underwent follow‐up biopsies. The Wilcoxon signed‐rank test showed significant improvement in the Baff scores for “ti”, “i‐IFTA”, “t” and “t‐IFTA” after treatment. On pathology, 13 (57%) of the patients who underwent follow‐up biopsy improved to “no evidence of rejection” or “borderline change.” Assuming that improvement in pathology to “borderline change” or “no evidence of rejection” on follow‐up biopsy indicates response to treatment, multivariate logistic analysis showed that lower UPCR was a predictive factor for response to treatment. No specific effect of treatment type was observed. Conclusions Our results indicate that treatment could improve the pathological findings in CA‐TCMR. SUMMARY AT A GLANCE A total of 32 of the 37 patients with CA‐TCMR were treated. 13 (57%) of the 23 patients who underwent follow‐up biopsy after treatment improved to no evidence of rejection or borderline change on pathology. Lower UPCR was a predictive factor for response to treatment. No specific effect of treatment type was observed.