Retrospective Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Oct 7, 2015; 21(37): 10669-10674
Published online Oct 7, 2015. doi: 10.3748/wjg.v21.i37.10669
Five-year sequential changes in secondary antibiotic resistance of Helicobacter pylori in Taiwan
I-Ting Wu, Seng-Kee Chuah, Chen-Hsiang Lee, Chih-Ming Liang, Lung-Sheng Lu, Yuan-Hung Kuo, Yi-Hao Yen, Ming-Luen Hu, Yeh-Pin Chou, Shih-Cheng Yang, Chung-Mou Kuo, Chung-Huang Kuo, Chun-Chih Chien, Yu-Shao Chiang, Shue-Shian Chiou, Tsung-Hui Hu, Wei-Chen Tai
I-Ting Wu, Seng-Kee Chuah, Chih-Ming Liang, Lung-Sheng Lu, Yuan-Hung Kuo, Yi-Hao Yen, Ming-Luen Hu, Yeh-Pin Chou, Shih-Cheng Yang, Chung-Mou Kuo, Chung-Huang Kuo, Shue-Shian Chiou, Tsung-Hui Hu, Wei-Chen Tai, Division of Hepatogastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833, Taiwan
Chen-Hsiang Lee, Division of Infectious Diseases, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833, Taiwan
Chun-Chih Chien, Yu-Shao Chiang, Department of Laboratory Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 833, Taiwan
Author contributions: Wu IT wrote the paper; Chuah SK, Lee CH, Liang CM, Lu LS, Kuo YH, Yen YH, Hu ML, Chou YP, Yang SC, Kuo CM, Kuo CH, Chien CC, Chiang YS, Chiou SS, Hu TH and Tai WC designed the concept, drafted and revised the article; Tai WC approved the final paper.
Institutional review board statement: This retrospective chart review study was approved by both the Institutional Review Board and the Ethics Committee of Chang Gung Memorial Hospital, Taiwan (IRB-104-1245B).
Informed consent statement: The Ethics Committee waived the requirement for informed consent, and each patient’s medical records were anonymized and redacted prior to access.
Conflict-of-interest statement: The authors declare no conflicts of interest.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Wei-Chen Tai, MD, Division of Hepatogastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, 123, Ta-Pei Road, Niao-Sung Hsiang, Kaohsiung 833, Taiwan. luketai1019@gmail.com
Telephone: +886-7-7317123-8301 Fax: +886-7-7322402
Received: July 5, 2015
Peer-review started: July 7, 2015
First decision: July 19, 2015
Revised: August 8, 2015
Accepted: September 2, 2015
Article in press: September 2, 2015
Published online: October 7, 2015
Processing time: 85 Days and 4.9 Hours
Abstract

AIM: To determine changes in the antibiotic resistance of Helicobacter pylori (H. pylori) in southern Taiwan after failure of first-line standard triple therapy.

METHODS: We analyzed 137 H. pylori-infected isolates from patients who experienced eradication failure after standard first-line triple therapy from January 2010 to December 2014. The H. pylori strains were tested for susceptibility to amoxicillin, clarithromycin, levofloxacin, metronidazole and tetracycline using the E-test method. The minimal inhibitory concentration (MIC) was determined by the agar dilution test. MIC values of ≥ 0.5, ≥ 1, ≥ 1, ≥ 4 and ≥ 8 mg/L were considered to be the resistance breakpoints for amoxicillin, clarithromycin, levofloxacin, tetracycline and metronidazole, respectively.

RESULTS: A high resistance rate was found for clarithromycin (65%-75%) and metronidazole (30%-40%) among patients who failed first-line standard therapy. The resistance levels to amoxicillin and tetracycline remained very low; however, levofloxacin resistance was as high as 37.5% in 2010 but did not increase any further during the past 5 years. The rates of resistance to these antibiotics did not show a statistically significant upward or downward trend.

CONCLUSION: Antibiotic resistance of H. pylori remains a problem for the effective eradication of this pathogen and its associated diseases in Taiwan. High clarithromycin resistance indicated that this antibiotic should not be prescribed as a second-line H. pylori eradication therapy. Moreover, levofloxacin-based second-line therapy should be used cautiously, and the local resistance rates should be carefully monitored.

Keywords: Helicobacter pylori; Antibiotic resistance; Five-year sequential changes; Failed first-line therapy; Southern Taiwan

Core tip: Antibiotic resistance of Helicobacter pylori (H. pylori) is one of the major causes of eradication therapy failure. This study was designed to assess the 5-year sequential changes in antibiotic resistance of H. pylori in southern Taiwan after the failure of first-line standard triple therapy. The rates of resistance to antibiotics did not show a statistically significant upward or downward trend. Antibiotic resistance of H. pylori has remained a problem in the effective eradication of this type of bacteria in Taiwan. High clarithromycin resistance indicated that this antibiotic should not be prescribed as a second-line therapy for H. pylori eradication. Therefore, levofloxacin-based second-line therapy should be used cautiously, and the local resistance rates should be carefully monitored.