Clarithromycin‐resistance and point mutations in the 23S rRNA gene in Helicobacter pylori isolates from Japan

Umegaki, Noriko; Shimoyama, Tadashi; Nishiya, Daisuke; Suto, T; Fukuda, Shinsaku; Munakata, Akihiro

doi:10.1046/j.1440-1746.2000.02072.x

Cited by 29 publications

(29 citation statements)

References 16 publications

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“…Resistance to clarithromycin observed before the year 2000 in this study is probably due to the use of the antimicrobial agent for other infections. The reported prevalence of H. pylori resistance to clarithromycin in Japan is reported at 6-21% [11,13,16,24,25]. The reported prevalence in western countries is from 1 to 17% [9,10,15,19,26].…”

Section: Discussionmentioning

confidence: 99%

Characteristics and Trends of Clarithromycin-Resistant Helicobacter pylori Isolates in Japan over a Decade

et al. 2004

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Clarithromycin has been administered to patients in Japan since 1991. Clarithromycin-resistant Helicobacter pylori strains have been on the rise in Japan. We obtained H. pylori isolates between 1989 and 2000 and examined mutations of the 23S rRNA gene, which are closely associated with clarithromycin resistance. Isolates were obtained from 356 patients with H. pylori infection treated at the Hiroshima University. Sixty-one of the patients received clarithromycin-based H. pylori eradication therapy. Mutations of the 23S rRNA gene were examined by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) followed by sequencing analysis. Mutant strains were found in 42 of the 356 patients (11.8%). The prevalence of mutant strains increased from 0 to 20.4% during the 12-year study period. The prevalence increased to more than 10% by 1995 and then to more 20% after 1999. The H. pylori eradication rate was significantly higher in patients with wild-type strains than in patients with mutant strains (72.0 vs. 36.4%, p = 0.024). Our data indicate that clarithromycin-resistant H. pylori strains have increased rapidly since 1995 and that the effectiveness of clarithromycin-based H. pylori eradication therapies may soon be compromised. Other new therapies may be necessary as first-line treatments in Japan.

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Section: Discussionmentioning

confidence: 99%

Characteristics and Trends of Clarithromycin-Resistant Helicobacter pylori Isolates in Japan over a Decade

et al. 2004

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“…Chromosomal DNA of the isolates was extracted by the cetyltrimethylammonium bromide method. A 1,300-bp fragment of the 23S rRNA (bp 1627 to 2926; GenBank accession number U27270) was amplified with primers Cla1 (5Ј-G GCTCTTTGAGTCCTTTTAGGAC-3Ј) and Cla4 (5Ј GCAT TACTGCGCTCACACAT-3Ј) as described previously (21). The PCR product was purified with a Microcon centrifugal filter device (Millipore Corporation, Bedford, Mass.…”

Section: Eradication Ofmentioning

confidence: 99%

T2182C Mutation in 23S rRNA Is Associated with Clarithromycin Resistance in Helicobacter pylori Isolates Obtained in Bangladesh

Khan

Nahar

Sultana

et al. 2004

Antimicrob Agents Chemother

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Twelve clarithromycin-resistant (MIC, >1 g/ml) Helicobacter pylori isolates were analyzed for point mutations in the 23S rRNA gene. Sequence analysis of all of the resistant isolates revealed a T-to-C transition mutation at position 2182. Transformation experiments confirmed that a single T-to-C transition mutation at position 2182 is associated with clarithromycin resistance. Eradication ofHelicobacter pylori infection by treatment with two antimicrobials (clarithromycin and amoxicillin or metronidazole) and a proton pump inhibitor is recommended by various consensus groups (5, 13). The prevalence of antimicrobial susceptibility of H. pylori varies with geographical regions, and clarithromycin resistance is the major cause of treatment failure (3,5,20). Alteration in either one or both copies of the H. pylori 23S rRNA gene is associated with resistance to clarithromycin, and the mechanism is a point mutation (an adenine-to-guanine transition at either position 2142 or 2143 or an adenine-to-cytosine transversion at position 2142) of the 23S rRNA (2,8,15,18,19,23). However, a T2182C mutation has also been proposed to be associated with clarithromycin resistance (10). In the present study we have examined clarithromycin-resistant (Cla r ) H. pylori (CRHP) isolates and characterized a T2182C mutation involved in clarithromycin resistance.Twelve CRHP isolates and three clarithromycin-susceptible H. pylori (CSHP) strains isolated from individual pretreatment patients attending the Dhaka Medical College hospital during 1999 to 2001 for routine endoscopy were examined. The bacteria were grown in brain heart infusion (BHIB) agar with 7% sheep blood and incubated at 37°C in 5% O 2 -10% CO 2 -85% N 2 for 3 to 6 days. A pure culture from a single colony was stored at Ϫ70°C until further study.The MICs of clarithromycin for the isolates were determined by the agar dilution method (MIC breakpoint, Ն1 g/ ml) and by the E-test strip (AB Biodisk, Solna, Sweden) as described elsewhere (11,12,16). All tests were repeated twice, and CSHP strain 26695 (MIC, 0.032 g/ml) was used as a control. Chromosomal DNA of the isolates was extracted by the cetyltrimethylammonium bromide method. A 1,300-bp fragment of the 23S rRNA (bp 1627 to 2926; GenBank accession number U27270) was amplified with primers Cla1 (5Ј-G GCTCTTTGAGTCCTTTTAGGAC-3Ј) and Cla4 (5Ј GCAT TACTGCGCTCACACAT-3Ј) as described previously (21). The PCR product was purified with a Microcon centrifugal filter device (Millipore Corporation, Bedford, Mass.), and a cycle sequencing reaction was performed with the same primers. DNA sequencing was performed under standard conditions with an ABI PRISM 310 automated sequencer (PerkinElmer Applied Biosystems, Foster City, Calif.). DNA sequence editing and analysis were performed by DNASTAR package 5.06 (DNASTAR Inc.) software. In order to confirm the role of the T2182C mutation, the 1,300-bp PCR fragment from CRHP isolate Gj50 (MIC, 4 g/ml) was transformed to CSHP strain DM26B as described earlier (19). Briefly, exponentially growing CSH...

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“…30) Some reports have associated A2143G mutation with higher MIC (Ͼ25 mg/l) to clarithromycin than A2144G mutation and that the frequency of later mutation is higher than former. 31) Contrarily, a recent report by Rimbara et al, suggested that not all A2143G mutations render high resistance to clarithromycin. 32) Infact, all nine CR strains analyzed in our study revealed the A2144G mutation in 23s rRNA gene, however MIC's of the all the strains had a wide variation (MIC: 8-Ͼ256 mg/l).…”

Section: Discussionmentioning

confidence: 99%

Potent Bactericidal Constituents from Mallotus philippinensis against Clarithromycin and Metronidazole Resistant Strains of Japanese and Pakistani Helicobacter pylori

Zaidi

Yoshida

Butt

et al. 2009

Biological & Pharmaceutical Bulletin

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In the quest for potent anti-Helicobacter pylori agents, we found 70% EtOH extract of Mallotus philippinensis (LAM.) MUELL. (MPM) with strong bactericidal activity at the concentration of 15.6-31.2 mg/l against eight H. pylori strains. Further fractionation and purification of 70% EtOH extract of MPM led to the isolation of 5 compounds, namely 5,7-dihydroxy-8-methyl-6-prenylflavanone (1), 3 -prenylrubranine (2), red compound (3), isorottlerin (4), and rottlerin (5) which were elucidated on the basis of nuclear magnetic resonance and mass spectroscopy. Among the isolated compounds, rottlerin exhibited most potent bactericidal activity with minimum bactericidal concentration (MBC) value of 3.12-6.25 mg/l against several clinical H. pylori isolates including Japanese and Pakistani strains, nine clarithromycin resistant (CR), and seven metronidazole resistant (MR) strains. Minimum inhibitory concentration (MIC) values of CR (8-Ͼ Ͼ256 mg/l) and MR (Ͼ Ͼ256 mg/l) strains were analyzed by E test. Moreover, the clarithromycin resistant strains were evaluated for A2143G and A2144G point mutations of 23s rRNA gene to correlate the MBC values with mutation type. Our results revealed the potent in vitro anti-H. pylori activity of MPM and rottlerin, specially against CR and MR strains, which could be gainfully utilized for the development of novel antimicrobials to prevent H. pylori related disorders.

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Clarithromycin‐resistance and point mutations in the 23S rRNA gene in Helicobacter pylori isolates from Japan

Cited by 29 publications

References 16 publications

Characteristics and Trends of Clarithromycin-Resistant <i>Helicobacter pylori</i> Isolates in Japan over a Decade

Characteristics and Trends of Clarithromycin-Resistant <i>Helicobacter pylori</i> Isolates in Japan over a Decade

T2182C Mutation in 23S rRNA Is Associated with Clarithromycin Resistance in Helicobacter pylori Isolates Obtained in Bangladesh

Potent Bactericidal Constituents from Mallotus philippinensis against Clarithromycin and Metronidazole Resistant Strains of Japanese and Pakistani Helicobacter pylori

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