Biomarkers for monitoring therapeutic side effects or various supratherapeutic confounders after kidney transplantation.

Although the development of novel immunosuppressants dramatically decreased the incidence of acute allograft rejection episodes, long-term allograft survival has not improved due to various postoperative confounders. These confounders include heterologous immunity by cytomegalovirus (CMV) infection, nephrotoxicity of immunosuppressants, ureteral complications, and onset of the original renal disease in the graft, which can mislead physicians from the actual diagnosis. Early and precise discrimination of these complications by using noninvasive biomarkers will benefit the patients at high-risk and be instructive in directing effective and timely therapies whenever necessary.