幽门螺杆菌抗生素耐药机制研究进展

幽门螺杆菌(Helicobacter pylori,H.pylori)感染可引起消化性溃疡、胃粘膜相关淋巴组织淋巴瘤和胃癌。随着抗生素耐药性的问题越来越严重,耐药机制的研究也不断深入。分子检测方法,尤其是核酸检测技术,可高效、快速、准确地检测幽门螺杆菌抗生素耐药基因及突变,对幽门螺杆菌感染的临床治疗发挥重要的指导作用,同时也可对幽门螺杆菌抗生素耐药性进行大规模及时有效监控。本文讨论了关于幽门螺杆菌抗生素耐药机制并着重总结了相关耐药基因及突变。     

抗幽门螺杆菌药物的研究进展

幽门螺杆菌(Helicobacter pylori)是引起胃炎、胃和十二指肠溃疡乃至胃癌的主要致病菌。近年来,随着大量广谱抗生素的广泛应用使得耐药的幽门螺杆菌菌株呈不断上升趋势,开发高效和高选择性的抗幽门螺杆菌药物已经成为全球关注的课题。本文对近五年来文献报道的抗幽门螺杆菌药物和先导化合物分类进行简要综述,为研究开发幽门螺杆菌感染性疾病的治疗新药提供参考。     

48例消化性溃疡患者幽门螺杆菌的耐药性调查

对幽门螺杆菌 (Helicobacterpylori ,Hp)临床分离株进行药物敏感性试验及耐药性分析 ,为探求幽门螺杆菌感染的根除疗法提供依据。运用微需氧培养方法 ,从胃镜活检标本中分离幽门螺杆菌 ,利用琼脂稀释法测定幽门螺杆菌对抗生素的敏感性试验 ,将 2 1株Hp临床分离株进行 7种抗菌药物的敏感性及耐药性调查。从 4 8例消化性溃疡患者胃镜活检标本中分离出 2 1株幽门螺杆菌。 2 1株幽门螺杆菌对阿莫西林MIC范围 0 .5～ 8mg/L ,无耐药菌株 ;克拉霉素、替硝唑的MIC范围分别为 0 .12 5～ 0 .5mg/L和 4～ 8mg/L ,耐药率均为 4 .76 % ;四环素、利福平的MIC范围分别为 0 .5～ 1mg/L和 1～ 6 4mg/L ,耐药率分别为 4 .76 % ,9.5 2 % ;甲硝唑的MIC为 16～ 12 8mg/L ,红霉素的MIC为 0 .5～ 12 8mg/L ,耐药率较高 ,分别为 2 3.89%和5 7.15 %。此次分离的Hp对阿莫西林、克拉霉素、替硝唑有较高的敏感性 ;而对甲硝唑及红霉素耐药率高 ,应避免应用 ;阿莫西林、克拉霉素可作为本地区治疗Hp感染的主要药物 ;四环素、利福平可用于一线治疗失败后二线治疗 ;替硝唑可替代甲硝唑用于Hp的根除治疗。     

益生菌在根除幽门螺杆菌中的应用

随着幽门螺杆菌耐药率的上升,幽门螺杆菌根除率逐渐下降,如何提高根除率是目前临床治疗上遇到的重要问题。益生菌不但能提高幽门螺杆菌根除率,还能降低根除幽门螺杆菌治疗的不良反应,益生菌在根除幽门螺杆菌中的应用越来越引起重视。     

幽门螺杆菌耐药机制研究进展

幽门螺杆菌耐药是一个全球性问题,由于耐药株的增多,给幽门螺杆菌感染的治疗带来困难,本文就该菌对常用抗生素的耐药机制作一综述。     

威海地区幽门螺杆菌耐药谱表型及遗传特征分析

目的研究威海地区的幽门螺杆菌对阿莫西林(AMX)、克拉霉素(CLA)、甲硝唑(MTZ)和四环素(TET)的耐药性表型和基因型。方法对172株分离自消化不良患者的幽门螺杆菌进行药敏试验检测,采用PCR法对甲硝唑耐药菌株进行rdx A和frx A基因的扩增。结果共检出耐4株阿莫西林耐药株(2.3%)、16株克拉霉素耐药株(9.3%),以及90株甲硝唑耐药株(52.3%)和6株四环素耐药株(3.5%)。所有甲硝唑耐药菌株中的rdx A基因发生了改变并直接导致Rdx A蛋白的氨基酸序列发生变化。在52株甲硝唑耐药株中发现frx A基因的错义突变,而在14株甲硝唑耐药株中检出了由于移码突变造成的frx A基因表达的提前终止。结论本地区的幽门螺杆菌对甲硝唑有较高的耐药率,与该类细菌染色体中rdx A和frx A基因的突变有关。     

耐药幽门螺杆菌的治疗新策略

幽门螺杆菌是一种常见的胃肠道细菌,与慢性胃炎、消化性溃疡、胃黏膜相关淋巴组织淋巴瘤和胃癌的发生密切相关。既然WHO已经将幽门螺杆菌归类为I类致癌物,那么根除幽门螺杆菌就显得尤为重要。然而,由于抗生素耐药、抗生素在胃低pH环境中活性降低以及在胃内停留时间不足,幽门螺杆菌的根除率正在逐年降低。本文通过回顾幽门螺杆菌的多重耐药情况,总结了有效的非抗生素抑制或者清除幽门螺杆菌的方法和策略,如益生菌、抗菌肽、纳米技术及中药等,并探讨相关的杀菌抑菌机制,为提高幽门螺杆菌的根除率及减少胃癌发生风险提供了新的理论依据和治疗策略。     

幽门螺杆菌STM文库重组质粒的构建

目的:应用信号标签突变技术(Signature tagged mutagenesis,STM)构建幽门螺杆菌突变体文库重组质粒。方法:采用平末端内切酶随机酶切幽门螺杆菌基因组DNA,并回收300～500bp片段(记作Fr),基因重组技术构建重组质粒pID700-Fr,电转化E.coliDH5α筛选阳性克隆,提取重组质粒酶切鉴定。结果:成功构建了1200个幽门螺杆菌STM文库重组质粒。结论:STM技术可用于幽门螺杆菌致病以及耐药相关基因的筛选,为幽门螺杆菌致病及耐药机理的研究奠定了基础。也将为幽门螺杆菌的治疗提供新的药物靶点。     

幽门螺杆菌根除疗法对肠道微生态的影响

幽门螺杆菌(Helicobacter pylori)感染是世界范围关注的焦点,进行幽门螺杆菌根除治疗是世界各国针对感染所采取的一项重要举措。但随着幽门螺杆菌耐药率,尤其是对大环内酯类药物耐药率的增加,标准三联疗法根除效果逐渐不能满足需求,更多的疗法得以推出。但是新推出的诸多疗法都应用了比以前更大剂量、更多种类甚至更长疗程的抗生素,这对于肠道微生物的微生态结构和数量都可能造成严重影响,甚至可能产生严重的副作用,同时也可能会对其耐药性产生影响。本文回顾了近20年来幽门螺杆菌根除治疗对肠道微生态的影响和一些新型实验疗法的研究结果,以对上述问题进行探讨。     

布拉酵母菌补充三联疗法根除儿童幽门螺杆菌的疗效: 随机对照试验的Meta分析

目的探讨补充布拉酵母菌的三联疗法对儿童幽门螺杆菌根除率和治疗相关副作用的疗效。方法电子检索数据库,包括CNKI、VIP、WanFang、Embase、The Cochrane Library和PubMed。搜集布拉酵母菌补充三联疗法治疗儿童幽门螺杆菌感染的随机对照试验(RCT)。检索时间从建库到2019年8月。两名研究者独自完成文献筛选、提取资料和质量评价。采用RevMan 5.3软件进行Meta分析。结果共纳入6项研究,计1 114例患儿。Meta分析结果显示,布拉酵母菌组与对照组相比,可提高幽门螺杆菌根除率[OR=2.02,95%CI(1.48,2.76),P0.001]。补充布拉酵母菌显著降低了腹泻[OR=0.42,95%CI(0.29,0.60),P0.001]、便秘[OR=0.35,95%CI(0.23,0.52),P0.001]、口腔炎[OR=0.24,95%CI(0.13,0.43),P0.001]等的发生率。两组研究资料在恶心、呕吐、腹痛发生率方面差异均无统计学意义。结论现有证据表明,布拉酵母菌作为三联疗法的辅助手段,可以提高幽门螺杆菌的根除率,并减少儿童治疗相关腹泻、便秘、口腔炎的发生率。但受纳入样本量和质量限制,需进一步开展大规模高质量随机对照试验加以验证。     

The evolution of Helicobacter pylori antibiotics resistance over 10 years in Beijing, China

Objectives: To evaluate Helicobacter pylori antibiotics resistance evolution from 2000 to 2009 to amoxicillin, clarithromycin, metronidazole, tetracycline, levofloxacin and moxifloxacin in Beijing, China. Methods: A total of 374 H. pylori strains isolated from 374 subjects who had undergone upper gastrointestinal endoscopy from 2000 to 2009 were collected and examined by E‐test method for antibiotics susceptibility. Results: The average antibiotics resistance rates were 0.3% (amoxicillin), 37.2% (clarithromycin), 63.9% (metronidazole), 1.2% (tetracycline), 50.3% (levofloxacin) and 61.9% (moxifloxacin). Overall resistance to clarithromycin, metronidazole, and fluoroquinolone increased annually (from 14.8 to 65.4%, 38.9 to 78.8%, and 27.1 to 63.5%, in 2000 or 2006–2007 to 2009, respectively). The secondary resistance rates were much higher than primary rates to these antibiotics, which also increased annually in recent 10 years. Conclusions: The trend of clarithromycin, metronidazole, and fluoroquinolone resistance of H. pylori increased over time and the resistance to amoxicillin and tetracycline was infrequent and stable in Beijing. Clarithromycin, metronidazole, and fluoroquinolone should be used with caution for H. pylori eradication treatment.     

229例慢性胃炎患者幽门螺杆菌培养及耐药情况

目的了解慢性胃炎患者H.pylori感染及其耐药情况,为临床治疗提供参考。方法慢性胃炎患者胃镜活检标本培养分离H.pylori,对分离的H.pylori采用纸片扩散法进行耐药性检测。结果229例患者分离出97株H.pylori;H.pylori分离阳性率为42．36％（97／229）,其中男性分离率为43．79％（67／153）,女性分离率为39．47（30／76）;92株H.pylori对抗生素的耐药性分别为：甲硝唑8．7％,克拉霉素7．6％,阿莫西林1．1％、呋喃唑酮1．1％,阿奇霉素4．4％,左氧氟沙星0％。结论慢性胃炎患者H.pylori感染率较高,但与性别、年龄无关;慢性胃炎H.pylori对常用抗生素敏感,建议采用左氧氟沙星、阿莫西林、呋喃唑酮进行治疗。     

Alaska sentinel surveillance for antimicrobial resistance in Helicobacter pylori isolates from Alaska native persons, 1999-2003

BACKGROUND: Previous studies in Alaska have demonstrated elevated proportions of antimicrobial resistance among Helicobacter pylori isolates. MATERIALS AND METHODS: We analyzed H. pylori data from the Centers for Disease Control and Prevention (CDC)'s sentinel surveillance in Alaska from July 1999 to June 2003 to determine the proportion of culture-positive biopsies from Alaska Native persons undergoing routine upper-endoscopy, and the susceptibility of H. pylori isolates to metronidazole [minimum inhibitory concentration (MIC) of > 8 g metronidazole/mL), clarithromycin (MIC > or = 1), tetracycline (MIC > or = 2) and amoxicillin (MIC > or = 1)] using agar dilution. RESULTS: Nine-hundred sixty-four biopsy specimens were obtained from 687 participants; 352 (51%) patients tested culture positive. Mean age of both culture-positive and culture-negative patients was 51 years. Metronidazole resistance was demonstrated in isolates from 155 (44%) persons, clarithromycin resistance from 108 (31%) persons, amoxicillin resistance from 8 (2%) persons, and 0 for tetracycline resistance. Metronidazole and clarithromycin resistance varied by geographic region. Female patients were more likely than male subjects to show metronidazole resistance (p < .01) and clarithromycin resistance (p = .05). CONCLUSIONS: Resistance to metronidazole and clarithromycin is more common among H. pylori isolates from Alaska Native persons when compared with those from elsewhere in the USA.     

Prevalence of Primary Fluoroquinolone Resistance Among Clinical Isolates of Helicobacter pylori at a University Hospital in Southern Taiwan

Background:  Fluoroquinolone-containing therapy is effective in eradicating Helicobacter pylori . However, the resistance rate of H. pylori to fluoroquinolones in Taiwan has not yet been reported. In this study, we aimed to investigate the susceptibility to antibiotics commonly used in eradication schedules and fluoroquinolones in H. pylori .
Methods:  A total of 210 clinical isolates of H. pylori were collected from April 1998 to September 2007 from patients in southern Taiwan. The in vitro activities of six antimicrobial agents were determined by the agar dilution method and Etest. The mutations in quinolone resistance-determining regions of gyrA and gyrB were investigated by direct sequencing.
Results:  Overall, 5.7% of the isolates were resistant to ciprofloxacin and levofloxacin. The resistance rate to amoxicillin, clarithromycin, metronidazole, and tetracycline was 1.0% (two of 210), 9.5% (20 of 210), 27.6% (58 of 210), and 0.5% (one of 210), respectively. The resistance rate to either ciprofloxacin or to levofloxacin increased from 2.8% (1998–2003) to 11.8% (2004–2007). The mutations in gyrA at N87 or D91 had an impact on primary fluoroquinolone resistance in H. pylori . Garenoxacin, but not moxifloxacin, had a good in vitro inhibitory effect against ciprofloxacin/levofloxacin-resistant strains compared with objective minimal inhibitory concentration values.
Conclusions:  Drug resistance to ciprofloxacin and levofloxacin in H. pylori collected from 2004 to 2007 increased significantly compared with resistance level observed during 1998–2003. The continuous surveillance of quinolone resistance among H. pylori is important in this area.     

上海市某三甲医院幽门螺杆菌耐药性和毒力与其生物膜形成能力的相关性研究

为探讨复旦大学附属华东医院(以下简称本院)分离培养的幽门螺杆菌(Helicobacter pylori,H. pylori)的耐药性、毒力和感染特征与其生物膜形成能力的相关性,收集2014年12月-2015年6月于本院消化内镜中心的胃活检组织标本及相应临床病例资料,分离培养获得幽门螺杆菌,分析菌株的耐药性、毒力基因型、临床病例特征。结果显示,从胃活检组织样本中共分离培养28株幽门螺杆菌,对左氧氟沙星(levofloxacin,LEV)、甲硝唑(metronidazole,MTZ)和克拉霉素(clarithromycin,CLA)的耐药率分别为32%、75%和11%,未发现阿莫西林(amoxicillin,AMX)耐药。单一药物耐药17株(17/28,61%),双重耐药10株(10/28,36%)。毒力基因cagA、oipA和vacAs1检出率为100%,未检出vacAs2。基因型vacAs1m1占39%(11/28),vacAs1m2占61%(17/28);iceA1占54%(15/28),iceA2占21%(6/28),iceA1A2占25%(7/28);dupA^＋占36%(10/28)。28株菌株均能形成生物膜,但能力不尽相同。单因素及独立样本t检验分析显示,45～59岁、iceA1^＋dupA^－基因型和甲硝唑敏感菌株形成生物膜的能力较强。结果提示,本院分离的幽门螺杆菌对甲硝唑耐药率最高,双重耐药不容忽视。菌株主要毒力基因型为cagA、oipA、vacAs1m2。幽门螺杆菌的生物膜形成能力与患者年龄有关,45～59岁组较强;携带毒力基因iceA1的菌株生物膜形成能力强;dupA基因型及甲硝唑耐药与菌株生物膜形成呈负相关。     

Time Trends of Helicobacter pylori Resistance to Antibiotics in Children Living in Vienna,Austria

Background: Increase of antibiotic resistance is a worldwide problem. Within the 4 years before the turn of the millennium Helicobacter pylori strains isolated in children living in Vienna, Austria, showed a primary clarithromycin and metronidazole resistance of 20% and 16%, respectively. The aim of this retrospective follow‐up survey was to assess the further development and current antimicrobial resistance status. Methods: Children having undergone upper endoscopy between March 2002 and March 2008 at the same two co‐operating pediatric gastroenterology units which had also been collaborating on the prior assessment were included. H. pylori infection was diagnosed by rapid urease test, histology, and culture. If the latter was positive, susceptibility testing to amoxicillin, clarithromycin and metronidazole by E‐test followed. From March 2004 onwards, susceptibility to levofloxacin, tetracycline and rifampin was additionally assessed. Results: Out of 897 children, 153 had a proven infection with H. pylori and no history of prior eradication treatment. Their median age was 11.5 years (range 0.5–20.9 years). Primary resistance to clarithromycin and metronidazole were 34% and 22.9%, respectively; dual resistance was found in 9.8% of the strains; 0.9% was resistant to tetracycline and rifampin, respectively. No case of amoxicillin resistance was detected. The only independent risk factor for clarithromycin resistance turned out to be the origin of a child from Austrian parents. Conclusions: In the last decade, the rate of primary resistance of H. pylori to clarithromycin continued to rise. No significant change was found regarding primary resistance to metronidazole or dual resistance to metronidazole and clarithromycin, respectively.     

Comparison of amoxicillin-metronidazole plus famotidine or lansoprazole for amoxicillin-clarithromycin-proton pump inhibitor treatment failures for Helicobacter pylori infection

BACKGROUND: Proton pump inhibitor-amoxicillin-metronidazole is recommended as second-line Helicobacter pylori therapy in Japan. The authors assessed the efficacy and safety of second-line eradication using the H2-receptor antagonist famotidine as a substitute for proton pump inhibitor. MATERIALS AND METHODS: Sixty-one patients who failed in first-line H. pylori eradication using proton pump inhibitor-clarithromycin-amoxicillin were randomly assigned to either second-line therapy including metronidazole: a 7-day course of lansoprazole 30 mg, amoxicillin 750 mg, and metronidazole 250 mg, b.i.d. (lansoprazole group); or a 7-day course of famotidine 40 mg, amoxicillin 750 mg, and metronidazole 250 mg, b.i.d. (famotidine group). Eradication was assessed for each group at least 4 weeks after completing eradication therapy. Drug susceptibility test was performed using 57 strains in pretreatment to clarithromycin, metronidazole, and amoxicillin. RESULTS: Prior to second-line H. pylori eradication, the rate of resistance to clarithromycin was high at 84% (48/57). Similarly, resistance to metronidazole was low at 5.3% (3/57); however, no amoxicillin-resistant strains were found. The eradication rates for both lansoprazole and famotidine treatment groups were high at 97% (29/30) and 94% (29/31), respectively. CONCLUSIONS: Famotidine treatment including metronidazole-amoxicillin as second-line therapy provided a high eradication rate similar to lansoprazole therapy. Famotidine is therefore expected to serve as a useful H. pylori eradication regimen in patients with proton pump inhibitor allergy, an economic benefit in terms of reduced health-care costs is also anticipated.     

Antibiotics resistance of Helicobacter pylori in children with upper gastrointestinal symptoms in Hangzhou,China

Background

The decreasing eradication rate of Helicobacter pylori is mainly because of the progressive increase in its resistance to antibiotics. Studies on antimicrobial susceptibility of H. pylori in children are limited. This study aimed to investigate the resistance rates and patterns of H. pylori strains isolated from children.

Materials and Methods

Gastric mucosa biopsy samples obtained from children who had undergone upper gastrointestinal endoscopy were cultured for H. pylori, and susceptibility to six antibiotics (clarithromycin, amoxicillin, gentamicin, furazolidone, metronidazole, and levofloxacin) was tested from 2012‐2014.

Results

A total of 545 H. pylori strains were isolated from 1390 children recruited. The total resistance rates of H. pylori to clarithromycin, metronidazole, and levofloxacin were 20.6%, 68.8%, and 9.0%, respectively. No resistance to amoxicillin, gentamicin, and furazolidone was detected. 56.1% strains were single resistance, 19.6% were resistant to more than one antibiotic, 16.7% for double resistance, and 2.9% for triple resistance in 413 strains against any antibiotic. And the H. pylori resistance rate increased significantly from 2012‐2014. There was no significant difference in the resistance rates to clarithromycin, metronidazole, and levofloxacin between different gender, age groups, and patients with peptic ulcer diseases or nonulcer diseases.

Conclusions

Antibiotic resistance was indicated in H. pylori strains isolated from children in Hangzhou, and it increased significantly during the 3 years. Our data strongly support current guidelines, which recommend antibiotic susceptibility tests prior to eradication therapy.     

A Randomized Clinical Trial to Determine the Efficacy of Regimens Containing Clarithromycin, Metronidazole, and Amoxicillin Among Histologic Subgroups for Helicobacter pylori Eradication in a Developing Country

Background: Most treatments deemed effective for Helicobacter pylori eradication in developed countries are less effective in developing countries. Regimens containing clarithromycin, metronidazole, and amoxicillin seem efficacious despite antibiotic resistance, and may be a viable option in developing countries. Materials and Methods: We evaluated the efficacy of a 14‐day regimen with 500 mg clarithromycin b.i.d., 500 mg metronidazole t.i.d., and 500 mg amoxicillin t.i.d. (with and without a proton pump inhibitor), and a 10‐day regimen containing 500 mg clarithromycin b.i.d., 1 g amoxicillin b.i.d., and 20 mg omeprazole b.i.d. in Pasto, Colombia, using a randomized, single‐blind design stratified by presence of atrophic gastritis. Results: H. pylori was eradicated in 86.8% and 85.3% of the participants randomized to a clarithromycin‐metronidazole‐amoxicillin and clarithromycin‐amoxicillin‐omeprazole regimens, respectively (p = .79). Per‐protocol analyses indicated greater efficacy for the clarithromycin‐metronidazole‐amoxicillin regimen (97%) versus the clarithromycin‐amoxicillin‐omeprazole regimen (86%) (p = .04), particularly for participants with atrophic gastritis (clarithromycin‐metronidazole‐amoxicillin = 100%, clarithromycin‐amoxicillin‐omeprazole = 81%; p = .02). Adverse events were mild, but adverse event‐related non‐compliance was reported more often for regimens containing clarithromycin, metronidazole, and amoxicillin. Conclusions: Our results suggest that an eradication rate of > 85% can be achieved with 14‐day clarithromycin, metronidazole, and amoxicillin and 10‐day clarithromycin, amoxicillin, and omeprazole regimens in Pasto, Colombia. The regimens containing clarithromycin, metronidazole, and amoxicillin appear to be superior to the clarithromycin, amoxicillin, and omeprazole regimen for compliant participants and those with atrophic gastritis. Our findings provide treatment options for a population in a developing country with a high prevalence of H. pylori infections and antibiotic resistance.