MTOR and viral infectious disease: Risk factors associated with the development of post-transplant de novo TMA include antibody-mediated rejection (ABMR), viral infections (CMV, BK virus, parvovirus B19), ischemic-reperfusion injury, immunosuppressive drugs (calcineurin inhibitors, mTOR inhibitors), ABO-incompatible transplant, and marginal kidneys [4-6].