 This study reports a case of a patient diagnosed with hepatitis B virus associated membranous nephropathy, HBVMN. The patient had a relapse of nephrodic syndrome when treated with lamivutine, but was remitted with entechovir. The authors found evidence of co-localized glomerular deposits of both hepatitis B surface antigen, HBSAG, and phospholipase A2 receptor, PLA2R, in the kidney biopsy. This suggests that the presence of HBVMN can be differentiated from other forms of MN by the presence of these two markers. Additionally, the authors observed that the relapse of nephrodic syndrome was correlated with the increase of HBSAG titers, which was reversed upon changing the antiviral agent. This article was authored by Yosuke Sasaki, Yoko Nagai, Tetsuo Mikami, and others.