Neural Epidermal Growth Factor-Like 1–Positive Membranous Nephropathy With Rheumatoid Arthritis

Abstract

Neural epidermal growth factor-like 1 (NELL1) is a recently described target antigen in membranous nephropathy (MN). NELL1-associated MN accounts for 1.5% to 8% of MN cases1-3,S1 and was reportedly associated with malignant diseases,2 lipoic acid supplementation,4 and consumption of traditional indigenous medicine containing mercury.5 Therefore, NELL1 may be an important antigen in secondary MN. Rheumatoid arthritis (RA) is an autoimmune inflammatory disease occasionally accompanied by MN. Complications of drugs, including gold salts, D-penicillamine, and bucillamine, are common causes of MN in patients with RA.