PURPOSE: This study aimed to determine the relation between CD38+ B-cell infiltration and outcome of transplant recipients diagnosed with chronic active antibody mediated rejection (caABMR). METHODS: A total of 67 patients transplanted from April 2003 and July 2021 with biopsy-proved caABMR were included. The density of CD3+ , CD20+ and CD38+ cells were quantified by immunohistochemical staining and baseline information, estimated glomerular filtration rate (eGFR) and 24 h urine quantitative protein at diagnose were collected. Receiver operating characteristic (ROC) curves were used to calculate the cut-off values in the prediction of graft loss and prognosis factors were further analyzed by Cox proportional-hazards analysis. Kaplan-Meier death-censored graft survivals of subgroups divided by CD38+ B-cell infiltration or urine quantitative protein were compared. RESULTS: The median density of CD3+ , CD20+ and CD38+ cells was 278, 167 and 89 (per mm CONCLUSION: A threshold of CD38+ B cell infiltration ≥ 93/mm