Impact of therapeutic dose monitoring of mycophenolic acid on the outcome of live-donor kidney transplant recipients - A prospective controlled study

Abstract

Immunosuppressive therapy is the backbone to renal transplantation. Although an adequate level of immunosuppression is required to dampen the immune response to the allograft, the level of chronic immunosuppression is slowly decreased over time (as the risk of acute rejection decreases) to help lower the overall risk of infection and malignancy. Several studies have discussed the clinical use of therapeutic drug monitoring of mycophenolic acid (MPA) in kidney transplant recipients. This prospective single-center study included 88 patients with endstage renal disease who were transplanted in Mansoura Urology and Nephrology Center from living related donors, from the beginning of February 2016 to the end of December 2016. Eight patients were excluded, the remaining 80 patients were divided into two groups; the study group (40 patients) who were followed up using therapeutic trough level monitoring of MPA and, control group (40 patients) who were followed up using the fixed-dose of Mycophenolate according to our local immunosuppressive protocol. These patients were followed up for one year posttransplantation with regard to graft function, rejection episodes, gastrointestinal (GI), and hematological side effects, the incidence of infection or malignancy, patient survival, and graft survival. Fifteen patients from the study group (37.5%) needed dose reduction of MPA, no patients needed to increase the dose. Our study showed insignificant differences regarding the patients' characteristics and demographic data. Significantly higher incidence of GI manifestations was noted in the control group (P = 0.001). Although the higher frequency of incidence of infection, anemia, leukopenia and thrombocytopenia was seen in the fixed- dose group, the difference was statistically insignificant. Regarding proteinuria and post-transplant diabetes mellitus, comparable data were obtained. Significantly higher percentage of recipients in the study group is still having normally functioning grafts (P = 0.02). Furthermore, higher percent of recipients in the control group died with functioning graft after one year of follow-up (P = 0.04). There were insignificant differences as regarding patient and graft survival. The decrease in the dose of MPA reduced the annual cost by around six thousand US dollars. Our results suggest that adopting therapeutic dose monitoring strategy during follow-up of kidney transplant recipients is adequate. Longer-term studies with a larger sample size may be needed to support this policy.