Chronic antibody rejection in renal allograft: An underestimated cause of renal allograft dysfunction

Introduction: Chronic antibody-mediated rejection (CAMR) has now emerged as one of the most common causes of chronic graft failure. In this study, we tried to study the clinical details, morphological features, risk factors, and outcome of biopsy-proven CAMR. Materials and Methods: This was a retrospective study including 14 patients' with biopsy-proven CAMR. The clinical details, posttransplantation duration, risk factors, histomorphological features, immunohistochemical features, treatment protocol, and graft outcome of all the patients were studied. Results: There were 11 male and 3 female patients and the mean age at biopsy was 33 +/- 10 years. The mean transplant duration to the diagnosis of CAMR was 61 months. The mean serum creatinine levels and 24-h proteinuria at the time of biopsy were 5.3 +/- 4.5 mg/dl and 3.4 +/- 0.9 g/24 h, respectively. Four patients had a previous episode of rejection and three patients had a concurrent hepatitis C virus (HCV) infection. Transplant glomerulopathy (TG) was seen in all 14 biopsies and all were positive for C4D in the peritubular capillaries. Twelve of these progressed to graft failure. Conclusion: CAMR is an important cause of chronic graft rejection, with a majority of cases progressing to graft failure. TG is the most commonly observed histomorphological pattern and the severity of TG seems to be associated with poor graft survival. An associated HCV infection further hinders the graft survival.