Masahiko Nakamura1, Anders Øverby2, Hirofumi Michimae3, Hidenori Matsui4, Shinichi Takahashi5, Katsuhiro Mabe6, Tadashi Shimoyama7, Makoto Sasaki8, Shuici Terao9, Tomoari Kamada10, Akinori Yanaka11, Junichi Iwamoto12, Satoshi Tanabe13, Akira Tari14, Shinji Nasu15, Hidekazu Suzuki16, Somay Yamagata Murayama17. 1. School of Pharmacy, Kitasato University, Tokyo, Japan. 2. Center of Education in Kongsvinger, Kongsvinger, Norway. 3. Department of Clinical Medicine (Biostatistics), School of Pharmacy, Kitasato University, Tokyo, Japan. 4. Kitasato Institute for Life Sciences, Kitasato University, Tokyo, Japan. 5. School of Medicine, Kyorin University, Mitaka, Japan. 6. Department of Gastroenterology, National Hospital Organization Hakodate National Hospital, Hakodate, Japan. 7. Aomori General Health Examination Center, Aomori, Japan. 8. Department of Gastroenterology, Aichi Medical University, Nagakute, Japan. 9. Kakogawa Central City Hospital, Kakogawa, Japan. 10. Department of Health Care Medicine, Kawasaki Medical School, Kurashiki, Japan. 11. University of Tsukuba Hitachi Medical Education and Research Center, University of Tsukuda, Hitachi, Japan. 12. Department of Gastroenterology, Tokyo Medical University Ibaraki Medical Center, Amicho, Japan. 13. Department of Advanced Medicine Research and Development Center for New Medical Frontiers, Kitasato University School of Medicine, Sagamihara, Japan. 14. Sixth Department of Internal Medicine, Hiroshima Red Cross Hospital & Atomic-bomb Survivors Hospital, Hiroshima, Japan. 15. Department of Gastroenterology, Ikeikai Inobe Hospital, Oita, Japan. 16. Division of Gastroenterology and Hepatology, Department of Internal Medicine, Tokai University School of Medicine, Isehara, Japan. 17. Laboratory of Medical Microbiology, School of Pharmacy, Nihon University, Funabashi, Japan.
Abstract
BACKGROUND: The clinical significance of non-Helicobacter pylori Helicobacter (NHPH) is still unknown. There are many reports of NHPH-infected patients suffering from gastric diseases. Here, we investigated the polymerase chain reaction (PCR) positivity of NHPH infection in gastric disease patients who were negative for H. pylori (Hp) by the rapid urease test and by pathological observation. MATERIALS AND METHODS: We collected the 296 endoscopically obtained gastric mucosal samples of Hp-negative gastric disease patients diagnosed based on a rapid urease test and pathology from 17 hospitals in Japan from September 2013 to June 2019, and we analyzed the existence of Hp and NHPH by PCR. The samples were also treated by indirect immunohistochemistry using an anti-Helicobacter suis VacA paralog antibody and were observed by confocal laser microscopy. RESULTS: Among the 236 non-Hp-eradicated cases, 49 cases (20.8%) were positive for NHPH. Among them, 20 cases were positive for Helicobacter suis, 7 cases were positive for Helicobacter heilmannii sensu stricto/ Helicobacter ailurogastricus (Hhss/Ha), and the other 22 cases could not be identified. The regional differences in the infection rates were significant. Forty percent of the nodular gastritis cases, 24% of the MALT lymphoma, 17% of the chronic gastritis cases, and 33% of the gastroduodenal ulcer cases were NHPH positive. Forty-five patients had been treated with one of the four types of combinations of a proton pump inhibitor and two antibiotics, and in all of these cases, the NHPH diagnosed by PCR was successfully eradicated. Immunohistochemistry using the Helicobacter suis-specific HsvA antibody coincided well with the PCR results. Among the 29 post-Hp eradication cases, three were NHPH positive, including one Hhss/Ha-positive case. Thus, approx. 20% of the Hp-negative non-Hp-eradicated gastric disease patients treated at 17 hospitals in Japan were infected with NHPH.
BACKGROUND: The clinical significance of non-Helicobacter pyloriHelicobacter (NHPH) is still unknown. There are many reports of NHPH-infectedpatients suffering from gastric diseases. Here, we investigated the polymerase chain reaction (PCR) positivity of NHPH infection in gastric diseasepatients who were negative for H. pylori (Hp) by the rapid urease test and by pathological observation. MATERIALS AND METHODS: We collected the 296 endoscopically obtained gastric mucosal samples of Hp-negative gastric diseasepatients diagnosed based on a rapid urease test and pathology from 17 hospitals in Japan from September 2013 to June 2019, and we analyzed the existence of Hp and NHPH by PCR. The samples were also treated by indirect immunohistochemistry using an anti-Helicobacter suis VacA paralog antibody and were observed by confocal laser microscopy. RESULTS: Among the 236 non-Hp-eradicated cases, 49 cases (20.8%) were positive for NHPH. Among them, 20 cases were positive for Helicobacter suis, 7 cases were positive for Helicobacter heilmannii sensu stricto/ Helicobacter ailurogastricus (Hhss/Ha), and the other 22 cases could not be identified. The regional differences in the infection rates were significant. Forty percent of the nodular gastritis cases, 24% of the MALT lymphoma, 17% of the chronic gastritis cases, and 33% of the gastroduodenal ulcer cases were NHPH positive. Forty-five patients had been treated with one of the four types of combinations of a proton pump inhibitor and two antibiotics, and in all of these cases, the NHPH diagnosed by PCR was successfully eradicated. Immunohistochemistry using the Helicobacter suis-specific HsvA antibody coincided well with the PCR results. Among the 29 post-Hp eradication cases, three were NHPH positive, including one Hhss/Ha-positive case. Thus, approx. 20% of the Hp-negative non-Hp-eradicated gastric diseasepatients treated at 17 hospitals in Japan were infected with NHPH.