Successful treatment of occult hepatitis B virus infection related membranous nephropathy after entecavir therapy.

We have reported a case of occult hepatitis B virus infection (OBI) associated membranous nephropathy (MN) with complete remission under an ongoing 3·5-year entecavir monotherapy. A 59-year-old man with a 3-year history of liver cirrhosis was introduced to our department because of oliguria, proteinuria and microscopic haematuria. He, with negative serum HBV surface antigen, was not detected HBV DNA in his serum. Renal biopsy was performed and was compatible with a diagnosis of hepatitis B virus-related membranous nephropathy (HBV-MN). The patient was prescribed diuretics and intravenous albumin, and his ascites and oedema remitted gradually. At the same time, entecavir 0·5 mg per day was started. Entecavir treatment was continuing for 3·5 years and finally resulted in complete remission of proteinuria. This suggests that entecavir monotherapy may induce and maintain complete remission of MN associated with OBI.