Similar Microvascular Inflammation and Tubulointerstitial Injury in ABO-Incompatible and Matched ABO-Compatible Kidney Allografts

ABO-incompatible (ABOi) kidney transplantation represents a viable tool to increase the donor pool for kidney transplantation, however, increased alloimmune response has been debated. The early outcomes of 25 low-risk ABOi kidney transplant recipients were compared with thoroughly matched 50 ABO-compatible (ABOc) ones. The matching process was based on gender and age of recipients and immunologic parameters, such as panel reactive antibodies, number of human leukocyte antigen mismatches, and transplantation era. Three-month protocol kidney graft biopsy Banff scores and 1-year clinical outcomes were compared. Apart from C4d positivity, no statistically significant differences were found regarding the Banff scores between the two groups. Similarly, microvascular inflammation and tubulointerstitial injury revealed no differences either. The eGFR at 3 months and 1 year was similar in both groups. In conclusion, blood group incompatibility yields no additional microvascular and tubulointerstitial graft injury if desensitization protocol was applied to low-risk kidney transplant recipients.