*Purpose: Multiple studies have shown acceptable deceased donor transplant (DDT) outcomes from A2 and A2B donors into B recipients; however, concerns remain for acute rejection and thrombotic microangiopathy. Per UNOS, transplant centers interested in participating in A2/A2B to B DDT are required to define and adhere to their own acceptable IgG anti-A2 titers. There is no cut off value required for IgM. IgM is a pentamer and can be easily cleared from circulation by plasmapheresis (TPE). At our center we have a IgG anti-A2 titre cut off limit of 1:8 for a potential B recipient. Here, we share our experience.

*Methods: Since the change in renal allocation policy in December 2014, we have performed 22 DDT from A2/A2B donors into B recipients. We performed peri-operative TPE in all these patients. All patients received thymoglobulin induction (4-6 mg/kg) and are maintained on Mycophenolate Mofetil and Tacrolimus. We use a Column Agglutination Technique with and without DTT (dithiothreitol) for Isoagglutinin testing at 2 separate occasions and then acceptable titers are updated in UNOS listing every 90 days. Our patients underwent 1 session of TPE pre- and at least one post-transplant.

*Results: From 2015 to 2019, twenty two A2/A2B into B, DDT were performed. Mean recipient age was 47 years and the majority were male (89%). The mean PRA was 18.5 and the mean donor KDPI was 56. Eighty nine percent of the deceased donors were A2 and the remaining were blood type A2B. Recipient anti-A2 untreated (IgM) ranged from 1:4 to 1:32 dilution. Four patients (21%) had rejection within 30 days of TX; one patient was noted to have Thrombotic microangiopathy on biopsy, which recovered with continuation of TPE. At 1 year, median serum creatinine was 1.3 mg/dl. At mean follow up of 18 months the patient and graft survival is 100%, and 96% respectively. One kidney allograft was lost due to post biopsy bleeding.

*Conclusions: Our data indicate that A2B/A2 to B renal transplantation can be done safely from the deceased donor. The addition of TPE is effective in lowering any potential immunological complication that may occur from IgM antibodies. IgM titers should be taken into consideration when planning for such ABO “incompatible” transplantation.

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