Noguchi Norihisa, Rimbara Emiko, Kato Ayami, Tanaka Akifumi, Tokunaga Kengo, Kawai Takashi, Takahashi Shin'ichi, Sasatsu Masanori
Department of Microbiology, School of Pharmacy, Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
Third Department of Internal Medicine, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo 181-8611, Japan.
J Med Microbiol. 2007 Sep;56(Pt 9):1174-1180. doi: 10.1099/jmm.0.47302-0.
The major cause of chemotherapy failure in patients with chronic gastritis and peptic ulcers caused by Helicobacter pylori is clarithromycin (CAM) resistance due to a mutation in the 23S rRNA gene. This study describes a non-invasive and accurate method for the detection of mixed CAM-resistant and -susceptible H. pylori by sequencing of the H. pylori 23S rRNA gene. Faeces were crushed with beads and the 23S rRNA gene was amplified using a nested PCR on the extracted DNA. Mutation analysis of this gene using this method showed that 20.4 % of patients carried mixed CAM-susceptible (wild type) and -resistant (A2142G or A2143G mutant) H. pylori. Furthermore, it was found that 66.6 % of patients who had been treated unsuccessfully carried one of these mutations in the 23S rRNA gene (including the mixed type), whilst standard culture detected CAM-resistant isolates in only 22.2 % of patients with unsuccessful treatment. These data suggest that, for successful therapy, the diagnosis method described here would more accurately detect CAM-resistant H. pylori, including mixed infections.
幽门螺杆菌引起的慢性胃炎和消化性溃疡患者化疗失败的主要原因是23S rRNA基因突变导致的克拉霉素（CAM）耐药。本研究描述了一种通过对幽门螺杆菌23S rRNA基因进行测序来检测混合性CAM耐药和敏感幽门螺杆菌的非侵入性准确方法。粪便用珠子研磨，提取的DNA通过巢式PCR扩增23S rRNA基因。使用该方法对该基因进行突变分析表明，20.4%的患者携带混合性CAM敏感（野生型）和耐药（A2142G或A2143G突变体）幽门螺杆菌。此外，发现66.6%治疗失败的患者在23S rRNA基因中携带这些突变之一（包括混合型），而标准培养仅在22.2%治疗失败的患者中检测到CAM耐药菌株。这些数据表明，为了成功治疗，本文所述的诊断方法能更准确地检测出CAM耐药幽门螺杆菌，包括混合感染。
