Recurrent membranous nephropathy and leiomyosarcoma in the renal allograft of a lupus patient

The frequency of membranous lupus nephritis recurrence (World Health Organization (WHO) class V) in the allograft after renal transplantation is unknown, but it appears uncommon (only two reported cases in the literature). Despite the increased incidence of sarcomas in organ transplant recipients (compared to the general population), non-Kaposi's sarcoma is an uncommon malignancy, and primary tumor involvement of a renal allograft is a rare occurrence. Our patient is a 28-year-old female with end-stage renal disease (ESRD) secondary to membranous lupus nephritis who received a living related transplant from her mother. At 26 months post-transplant, she presented with proteinuria and a rise in creatinine (Cr). Allograft biopsy was consistent with recurrent membranous nephropathy. Five weeks later, she was found to have a high-grade leiomyosarcoma originating within the allograft. We reviewed the literature on recurrent post-transplant membranous nephropathy and the possible role of the Epstein-Barr virus (EBV) infection in smooth muscle tumors occurring in organ transplant recipients. We also considered the association of membranous nephropathy and malignancy.