Antimicrobial resistance of Helicobacter pylori strains to five antibiotics, including levofloxacin, in Northwestern Turkey

Abstract

Introduction: Antibiotic resistance is the main factor that affects the effi cacy of current therapeutic regimens against Helicobacter pylori. This study aimed to determine the rates of resistance to effi cacy clarithromycin, amoxicillin, tetracycline, levofl oxacin and metronidazole among H. pylori strains isolated from Turkish patients with dyspepsia. Methods: H. pylori was cultured from corpus and antrum biopsies that were collected from patients with dyspeptic symptoms, and the antimicrobial susceptibility of H. pylori was determined using the E-test (clarithromycin, amoxicillin, tetracycline, metronidazole and levofl oxacin) according to the EUCAST breakpoints. Point mutations in the 23S rRNA gene of clarithromycin-resistant strains were investigated using realtime PCR. Results: A total of 98 H. pylori strains were isolated, all of which were susceptible to amoxicillin and tetracycline. Of these strains, 36.7% (36/98) were resistant to clarithromycin, 35.5% (34/98) were resistant to metronidazole, and 29.5% (29/98) were resistant to levofl oxacin. Multiple resistance was detected in 19.3% of the isolates. The A2143G and A2144G point mutations in the 23S rRNA-encoding gene were found in all 36 (100%) of the clarithromycin-resistant strains. Additionally, the levofl oxacin MIC values increased to 32 mg/L in our H. pylori strains. Finally, among the clarithromycin-resistant strains, 27.2% were resistant to levofl oxacin, and 45.4% were resistant to metronidazole. Conclusions: We conclude that treatment failure after clarithromycin-or levofl oxacinbased triple therapy is not surprising and that metronidazole is not a reliable agent for the eradication of H. pylori infection in Turkey.

Antibiotic resistance among <em>Helicobacter pylori</em> clinical isolates in Lima, Peru

“…An emerging appearance of H. pylori antibiotic resistance has also been reported from other parts of the world, including Asia, Europe, and the Americas 12,15–17,19,26–28. This observation, coupled with reports of H. pylori reinfection after successful antibiotic treatment,6,7 makes H. pylori treatment more challenging.…”

Prevalence of Primary Antimicrobial Resistance of H. pylori in Turkey: A Systematic Review

“…In a southern region study, the levofloxacin resistance rate was 18.2% in 2012 [11]. A western region study reported the prevalence of resistance to levofloxacin as 29.5% (breakpoint MIC ≥1 mg/L) [19].…”

“…In Turkey, there are very few studies for levofloxacin resistance rates for H. pylori, and the overall resistance of H. pylori to levofloxacin was detected in 31 (23.7%, 95% CI: 18-30.2) of 1059 total H. pylori strains isolated in Turkey. In a north region study (2014), the prevalence of primary resistance to levofloxacin was detected as 29.5%, and the MIC 90 value was >32 mg/L (breakpoint MIC ≥1 mg/L) [19]. In a north region study (2014), the prevalence of primary resistance to levofloxacin was detected as 29.5%, and the MIC 90 value was >32 mg/L (breakpoint MIC ≥1 mg/L) [19].…”

“…In clarithromycin resistance development, three point mutations may occur at the two nucleotide positions 2142 (A2142G and A2142C) and 2143 (A2143G) in the peptidyl transferase loop of the 23S rRNA gene. The point mutations responsible for the clarithromycin resistance were detected as A2143G and A2144G in Turkish studies [11,[17][18][19]. The point mutations responsible for the clarithromycin resistance were detected as A2143G and A2144G in Turkish studies [11,[17][18][19].…”

Current Status of H. pylori Infection Treatment 2017

“…At present, the eradication of H. pylori infection is main troubles antibiotic resistance, patients compliance and intolerance to therapeutic regimens (Niv et al, 2015). Antibiotic resistance is nowadays a major concern since one of the major causes of treatment failure against the H. pylori is drugs sensitive to this germ are getting resistant Caliskan et al, 2015;Filipa et al, 2011). The causes of resistance are poor drug penetration, low drug concentration, short gastric residence time and antibiotic resistance represent a significant health care burden on society.…”