Kidney transplant after hematopoietic cell transplant in pediatrics: Infectious and immunosuppressive considerations.

Pediatric patients requiring kidney transplant after hematopoietic cell transplant receive multiple courses of immunosuppression placing them at risk for infection. To elucidate potential risk factors for infection, we compared the immunosuppressive regimens and infectious complications of pediatric kidney transplant recipients at a single institution who had previously undergone hematopoietic cell transplant from different donors to similar patients reported in the literature. Among the initial four post-hematopoietic cell transplant kidney transplant patients reviewed, viremia episodes were universal, including BK virus, Epstein-Barr virus, and human herpesvirus-6, with one death from presumed BK virus encephalitis. No viremia was reported in five similar cases in the literature. Risk factors for increased infection include use of lymphodepleting serotherapy in HCT conditioning, multiple HCTs, limited immune reconstitution time between transplants, increased pre-KTx viral burden, and use of T-cell-depleting versus -suppressive induction immunosuppression for KTx. These findings suggest that pediatric post-HCT KTx recipients are at increased risk for viral infections, likely benefitting from thorough pre-KTx evaluation of immune reconstitution and preferential use of non-T-cell-depleting induction therapy for KTx. We applied these recommendations to one subsequent post-HCT patient requiring KTx at our institution with excellent outcomes one year post-KTx.