High prevalence of Helicobacter pylori infection in Japanese patients with membranous nephropathy T. MORIYAMA*  , T. KANEKO à , M. FUJII§, Y. TSUBAKIHARA à , S. KAWANO – & E. IMAI   *Health Care Center;  Department of Nephrology, Graduate School of MedicineàOsaka General Medical Center; §Osaka Koseinenkin Hospital; –School of Allied Health Science, Osaka University, Osaka, Japan Correspondence to: Dr T. Moriyama, Health Care Center, Osaka University, 1–17 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan. E-mail: moriyama@wellness.hss.osaka-u.ac.jp Publication data Accepted 15 February 2006 This article was originally published as: Moriyama T, Kaneko T, Fujii M, Tsubakihara Y, Kawano S, Imai E, Alimentary Pharmacology & Therapeutics symposium series 2006; 2(1), 189–193. Publication was supported by a grant from Taishotoyama Pharmaceutical Company Ltd, Tokyo, Japan. SUMMARY Background Membranous nephropathy is the most common cause of nephrotic syn- drome in Japanese adults, and is often precipitated by systemic diseases such as infection, neoplasm, and autoimmune conditions. Recently, the Helicobacter pylori antigen was detected histochemically in the glom- eruli of membranous nephropathy patients, raising the possibility that H. pylori may be the pathogen that causes. Aim To reveal the p1revalence of H. pylori infection in the Japanese mem- branous nephropathy population and to test the therapeutic efficacy of H. pylori eradication on the course of disease in membranous nephropa- thy patients. Methods The prevalence of H. pylori infection was investigated by the HM-CAP method in 32 membranous nephropathy patients and an age-matched control group (C: n ¼ 243). Results A significantly higher H. pylori infection rate was found in membra- nous nephropathy patients than in the control group (positive/total: membranous nephropathy 21/32 vs. C 108/243, P < 0.05 by chi-squared test). Eradication of H. pylori was achieved in four membranous nephropathy patients with proteinuria who were receiving glucocorti- coid therapy, three of whom experienced a reduction of proteinuria after eradication. Conclusions We found a higher prevalence of H. pylori infection in Japanese mem- branous nephropathy patients than in age-matched control subjects, which suggests the possible involvement of H. pylori infection in the pathogenesis of membranous nephropathy. Aliment Pharmacol Ther 24 (Suppl. 4), 189–193 Alimentary Pharmacology & Therapeutics ª 2006 The Authors 189 Journal compilation ª 2006 Blackwell Publishing Ltd doi:10.1111/j.1365-2036.2006.00044.x