Antibody-mediated rejection in pediatric kidney transplantation: pathophysiology, diagnosis, and management.

Kidney transplant is the preferred treatment of pediatric end-stage renal disease. One of the most challenging aspects of pediatric kidney transplant is the prevention and treatment of antibody-mediated rejection (ABMR), which is one of the main causes of graft dysfunction and early graft loss. Most challenges are similar to those faced in adult kidney transplants; however, factors unique to the pediatric realm include naivety of the immune system and the small number of studies and randomized controlled trials available when considering pharmacological treatment options. Here, we present a case of ABMR in a pediatric patient and a review of the pathophysiology, diagnosis, and management of ABMR. ABMR in pediatric kidney transplant continues to be a frustrating condition to treat because (1) there still remain many unidentified potential antigens leading to ABMR, (2) children and adults are at different stages of their immune system development, and, thus, (3) the full pathophysiology of alloimmunity is still not completely understood, and (4) the efficacy and safety of treatment in adults may not be directly translated to children. As we continue to gain a better understanding towards the precise alloimmune mechanism that drives a particular ABMR, we can also improve pharmacotherapeutic choices. With continued research, they will become more precise in treating a particular mechanism versus using a broad scope of immunosuppression such as steroids. However, there is much more to be uncovered, such as identifying more non-human leukocyte antigens and their role in alloimmunity, determining the exact mechanism of adults achieving complete operational tolerance, and understanding the difference between pediatric and adult transplant recipients. Making strides towards a better understanding of these mechanisms will lead to continued efficacy and safety in treatment of pediatric ABMR.