NELL1-Positive Membranous Nephropathy in Renal Allografts: A Series of Six Patients

Abstract

Membranous nephropathy (MN) is a major cause of nephrotic syndrome and neural epidermal growth factor-like 1 protein (NELL1) is the second most common inciting antigen. An increasing number of exposures and diseases have been associated with NELL1+ MN. There is limited data on NELL1 following kidney transplantation with only one prior reported case. Here, we describe 3 cases of recurrent and 3 cases of de novo NELL1+ MN. None of the patients in this series had known triggers of MN, such as malignancy or associated medications (including lipoic acid, bucillamine, tiotropin, or indigenous medicines). This suggests that NELL1, though not a podocyte antigen, may present as an idiopathic disease or transplantation may serve as an exposure for the development of NELL1+ MN.

Keywords: Membranous nephropathy; NELL1; case study; kidney biopsy; neural epidermal growth factor-like 1.