Can Aminoglycosides Be Used as a New Treatment forHelicobacter pylori?In vitroActivity of Recently IsolatedHelicobacter pylori

Background: Smectite can serve as a drug delivery system and gentamicin-intercalated smectite hybrids are expected to supersede the standard therapy for Helicobacter pylori eradication. The aim of this study was to confirm whether the minimum inhibitory concentration (MIC) of aminoglycosides applied as smectite hybrids remained low against recently isolated H. pylori strains. Materials and Methods: A total of 140 strains were collected for a minimum period of 3 years. Antimicrobial susceptibility tests were performed, and the MICs of eight antibiotics (amoxicillin, clarithromycin, metronidazole, tetracycline, levofloxacin, gentamicin, netilmicin, and tobramycin) were determined by using the Epsilometer test and following the European Committee on Antimicrobial Susceptibility Testing recommendations. Results: The resistance rate of clarithromycin was high, up to 30.7%, although it is a major antimicrobial agent used in standard therapy. The MIC 50 and MIC 90 of gentamicin (0.25 mg/L and 0.75 mg/L) and netilmicin (0.19 mg/L and 0.75 mg/L) were lower than other alternative therapies for H. pylori eradication. In clarithromycin-resistant strains, the MIC 50 was 0.25 mg/L and the MIC 90 was 1 mg/L for gentamicin; for netilmicin, the values were 0.25 mg/L and 0.75 mg/L, respectively. Conclusion: Through the use of gentamicin and netilmicin, which have low MICs for H. pylori, aminoglycoside-intercalated smectite hybrids are expected to emerge as a new standard therapy for H. pylori eradication.