Plasma Cell-Rich Rejection Processes in Renal Transplantation: Morphology and Prognostic Relevance

Abstract

Renal transplantation is the most effective therapy in end-stage renal disease. The prognosis of transplant survival is still determined by rejection. Morphologically, this involves interstitial rejection with potential development of vascular rejection (VR) and/or glomerular rejection processes, designated as transplant glomerulopathy (TGP). The cellular infiltrates are usually dominated by lymphocytes and macrophages in differing quantity, characterizing the severity of the rejection processes. In 14% of the renal transplant biopsies and explants in our investigation (n = 399) plasma cells (PR) predominate in the cellular infiltrate. To determine whether the enrichment of PR has an impact on graft function or could even constitute an independent parameter for transplant survival, we analyzed 109 cases of transplanted patients matched for AR and CR and divided them into those rich and those nonrich in PR. In the group rich in PR, PR comprised 30% of all infiltrates in comparison to 5% in the group non-rich in PR. VR and TGP appeared significantly more often in PR-rich rejections (P = 0.0044). The group rich in PR had a significantly more adverse prognosis (P = 0.0024), especially if PR enrichment was observed in the chronic rejection processes (P = 0.0148). In the Cox proportional hazard model the occurrence of VR was the only independent factor. In itself, plasma-cell enrichment is not a prognostic marker, but it is an indicator of a more adverse outcome because it is often accompanied by the appearance or subsequent development of VR +/- TGP. The detection of PR-rich rejection processes should therefore encourage the clinician to intensify the immunosuppressive schedule.