Plasma cell-rich rejection accompanied by acute antibody-mediated rejection in a patient with ABO-incompatible kidney transplantation

We report a case of plasma cell-rich rejection accompanied by acute antibody-mediated rejection in a patient with ABO-incompatible kidney transplantation. A 33-year-old man was admitted for an episode biopsy; he had a serum creatinine (S-Cr) level of 5.7mg/dL 1 year following primary kidney transplantation. Histological features included two distinct entities: (1) a focal, aggressive tubulointerstitial inflammatory cell (predominantly plasma cells) infiltration with moderate tubulitis; and (2) inflammatory cell infiltration (including neutrophils) in peritubular capillaries. Substantial laboratory examination showed that the patient had donor-specific antibodies for DQ4 and DQ6. Considering both the histological and laboratory findings, we diagnosed him with plasma cell-rich rejection accompanied by acute antibody-mediated rejection. We started 3 days of consecutive steroid pulse therapy three times every 2 weeks for the former and plasma exchange with intravenous immunoglobulin (IVIG) for the latter histological feature. One month after treatment, a second allograft biopsy showed excellent responses to treatment for plasma cell-rich rejection, but moderate, acute antibody-mediated rejection remained. Therefore, we added plasma exchange with IVIG again. After treatment, allograft function was stable, with an S-Cr level of 2.8mg/dL. This case report demonstrates the difficulty of the diagnosis of, and treatment for, plasma cell-rich rejection accompanied by acute antibody-mediated rejection in a patient with ABO-incompatible kidney transplantation. We also include a review of the related literature.