58-P

Abstract

Aim A study case. Methods A 50 years old man received living related renal allograft from his son on 20 Mar 2011. Patient HLA type was: HLA-A ∗ 31, B ∗ 51, C ∗ 15, DRB1 ∗ 13, DQB1 ∗ 06. Donor HLA type was: HLA-A ∗ 02, A ∗ 31, B ∗ 07, B ∗ 51, C ∗ 07,C ∗ 15, DRB1 ∗ 13, DRB1 ∗ 15, DQB1 ∗ 06. Thus sharing one haplotype with his donor (three A:B: DR mismatches). Historic PRA was negative. Flow and CDC cross matches were negative. Induction immunosuppression with basliximab, maintained on prednisolone, tacrolimus and mycophenolate moftiel. Results For six months post transplantation, his creatinine was less than 100, it reached 160 umol/L by September 2011. A biopsy, Luminex PRA and flow cross match were done. Single antigen Luminex PRA revealed the following specificities: DR103, DR9, DR10 (5-10,000 MFI) which are non-DSA and two specificities with DSA, HLA-A2 = 3674 MFI and HLA-DR51 = 9108 MFI. Flow cross match was negative. Biopsy showed the following pattern: Acute T-cell mediated (cellular) rejection, type IB (Banff update ‘09 – Acute tubulointerstitial rejection). Plus diffused linear and circumferential C4d staining in the majority of the cortical peritubular capillaries, suspicious for concurrent acute antibody-mediated rejection. Rescue treatment included methylprednisolone plus plasmapheresis and IVIG. During the last five months his creatinine went back to normal. Conclusions DSA in the presence of negative flow cross match may still cause damage to the graft.