How successful is the kidney transplant if the donor has a different blood group? does the graft have chancesof failing early?

Great if compatible: Excellent outcomes occur for kidney donors with different blood groups than their recipients if the pair is compatible (don a-recip ab; don b - recip ab; don o-recip a, b orab). Incompatible paired kidney transplants are subject to antibody based rejection due to the difference in blood types. Prevention with plasmapheresis, use of Rituxan (rituximab) is good not perfect. Yes, early failure can still happen.

These can work well: Blood group incompatable transplants (for example donor is a, recipient is o) can be done quite well with the addition of plasmapheresis prior to and after the transplant procedure. The main issue is what is called the "antibody titer" in the recipient. If the titer is low enough, a blood group incompatable transplant can be done. Many centers in the us offer this option.