Trough Level of Mycophenolic Acid Did Not Affect De Novo DSA Development in Kidney Transplantation

Abstract

IntroductionMycophenolate mofetil has improved long-term outcomes of kidney transplantation. However, the impact of mycophenolic acid (MPA) trough level on the development of de novo donor-specific anti-HLA antibody (DSA) is unclear. We examined the relation between MPA trough level and de novo DSA development. MethodWe retrospectively studied 617 kidney recipients whose MPA trough level and de novo DSA data were available. All patients underwent primary kidney transplant from living donors from 2008 to 2014, and were chronically treated with a calcineurin inhibitor, mycophenolate mofetil, and +/- steroids. They were equally divided into 4 groups according to the mean trough level of MPA (mMPA) at 1 year post-transplantation: Group 1, mMPA < 2.14 ng/mL (n = 152); Group 2, mMPA 2.14-2.83 ng/mL (n = 157); Group 3, mMPA 2.83-3.57 ng/mL (n = 153); and Group 4, mMPA ≥ 3.57 ng/mL (n = 155). The groups were compared by incidence rate of de novo DSA, graft survival rate, and renal function. ResultsThe incidence rates of de novo DSA were 33.3% in Group 1, 23.7% in Group 2, 22.9% in Group 3, and 30.3% in Group 4 (P = .158). Although there was no significant difference in graft survival rates, a significant difference of renal functions was noted: the higher the renal function, the lower the MPA trough level. ConclusionThe mMPA trough level at 1 year post-transplantation was not statistically associated with the incidence rate of de novo DSA after kidney transplantation.