Genome Analysis of Helicobacter pylor by Pulsed-field Gel Electrophoresis

作者研究了幽门螺杆菌的分子流行病学使用脉冲场凝胶电泳基因分型。在研究的第一年，作者尝试将该技术应用于根除治疗的疗效评价，使用了以下三种样品：1）来自不同患者的77株菌株，2）根除治疗前后的4例菌株，3）来自幽门前庭和胃体大弯的18例菌株。在1）中的77株中，75株显示不同的基因型，只有2株具有相同的基因型。这两种菌株是从两名在同一科室接受内窥镜检查的患者身上收集的，两名患者间隔10天，疑似通过医疗保健医生、内窥镜设备或工具交叉感染。1例来自B的病例根除治疗前后基因型不同，提示再次感染。在另外三个病例中，基因型p ...更多信息 发现再治疗和治疗后相同或高度相似;作者确定根除不完全。3）中18例中15例基因型相同。在3例病例中，一名50多岁的男性，一名60多岁的女性和一名60多岁的男性，观察到不同的基因型，并存在两个以上H. pylori建立。多个克隆的感染表明，每次感染的机会都受到重复感染，这被认为是感染率随年龄增长而增加的原因之一。观察AMPC、CAM和MNZ三种药物对幽门螺杆菌根除治疗的疗效。对每种药物的耐药性增加率与其他研究所的报告几乎相同。根除失败的病例中有一半感染了原发性耐药菌株。3例胃前庭和胃体大弯的菌株中有1株在两个部位表现出不同的敏感性，这些结果表明，联合使用基因分型和脉冲-现场凝胶电泳和药敏试验有助于评价根除治疗的疗效。少

The authors investigated the molecular epidemiology of Helicobacter pylori using genotyping with pulsed-field gel electrophoresis. In the first year of the investigation, the authors attempted to apply this technique to evaluation of the efficacy of eradication therapy.The following three strains of samples were used : 1) 77 strains from different patients, 2) strains from before and after eradication therapy in 4 cases, and 3) strains from the pyloric vestibule and greater curvature of the gastric body in 18 cases. Of the 77 strains in 1), 75 displayed a different genotype and only two had the same genotype. These two strains were collected from two patients who received an endoscopic examination at the same division with 10 days of one another, and cross infection via health-care physicians, the endoscopic device, or tools was suspected. The genotype pre- and post- eradication therapy in one case from B was different, which suggested re-infection. In three other cases, the genotype p … More re- and post-therapy was the same or a high degree of similarity was found ; the authors determined that the eradication was incomplete. Of the 18 cases in 3), the genotype was the same in 15. In 3 cases - a male in his 50s, a female in her 60s, and a male in his 60's - different genotypes were observed and existence of multi- infection with more than two clones of H. pylori was established. The infection by multiple clones suggests that repeated infection was received with each opportunity for infection and is thought to be one reason for the increase in the rate of infection with advancing age.After the second year, the authors investigated the correlation between sensitivity patterns of H. pylori for the three drugs AMPC, CAM, and MNZ and the efficacy of eradication therapy. The rate of increased resistance to each drug was almost identical to that in reports from other institutes. Half of the cases with failed eradication were infected with a primary resistant strain. One strain in the strains from the gastric vestibule and greater curvature of the gastric body in 3 cases displayed a different sensitivity pattern in two locations, and it established the existence of multi-infection with more than two clones with differing eradication drug sensitivity.These results demonstrated that combined use of genotyping with pulsed-field gel electrophoresis and sensitivity examination is helpful for evaluation of efficacy of eradication therapy. Less