Differential outcomes in 3 types of acute antibody-mediated rejection

Introduction: The aim of this study is to investigate the prevalence, predictors, and clinical outcomes of acute antibody-mediated rejection (AAMR). Methods: Retrospective analysis of 833 adult patients who received kidney transplantation between 1/1/2001 and 8/15/2007. Results: The prevalence of AAMR and acute cellular rejection was 2% and 8.2%, respectively. Eight patients had type I, seven type II, and two type III AAMR. All patients had at least one strong donor-specific anti-HLA antibodies (DSA) with a median fluorescence intensity (MFI) value of over 6000 and the mean number of strong DSAs was 2.0 ± 0.7. Fifteen of 17 patients received pre-transplant desensitization treatment. During a median 28 months of follow-up (range: 12-38 months), two patients died (88% patient survival), and nine lost their allografts (35% graft survival). While all type I AAMR patients responded to treatment, all type III patients, and four of seven patients with type II AAMR lost their allografts earlier, and three type II AAMR patients later due to transplant glomerulopathy. Conclusions: AAMR is mainly seen in patients with pre-transplant strong DSAs. There is a striking difference in clinical outcomes of AAMR that types II and III AAMR patients have poor prognosis compared to type I AAMR patients.