RESUMEN
BACKGROUND: There are few reports about the clinical course and prognosis of monoclonal gammopathy of undetermined significance (MGUS) in long-term immunosuppressed patients. Our aim was to study the association and evolution of MGUS and renal transplantation. METHODS: Subjects submitted to renal transplantation between 1996 and 2011 who presented MGUS before or after immunosuppressive treatment was established were selected. RESULTS: Patients (N = 587) underwent kidney transplantation in our center during the selected period. MGUS was detected in 17 (2.9%) patients (10 men and 7 women with a mean age of 69.9 ± 10.07 years), with a median follow-up of 6 years. All patients had a functioning graft. Nine had MGUS before transplantation. One patient had multiple myeloma, and 8 remained stable. Eight patients had development of MGUS after transplantation. Six patients remained stable, 1 showed no MGUS, and 1 displayed an increased monoclonal component in further controls. CONCLUSIONS: In our study, renal transplantation is not a risk factor for the development of malignant processes in patients with MGUS before transplantation. There is a group of patients who tend to have MGUS after transplantation; nevertheless, they had a benign evolution during a 6-year follow-up.
