Abstract
Background: Helicobacter pylori might become highly resistant to antibiotics taken through the life time of patients. This study
examined the change in antibiotic resistance of H. pylori by time.
Methods: Out of 985 dyspeptic patients who were referred to the endoscopy unit of Shariati hospital during 2010-2017, 218
patients with gastric biopsies positive for rapid urease test (RUT) and H. pylori culture were recruited in the study. H. pylori isolates
were examined for resistance to 8 currently used antibiotics by the disc diffusion method. Results were compared with those from
our three previous studies. The frequency of multidrug resistance (MDR) was also assessed.
Results: The highest resistance rate was to metronidazole (MTZ) (79.4%) followed by ofloxacin (OFX) (58.7%), ciprofloxacin
(CIP) (46.8%), levofloxacin (LVX) (45%), tetracycline (TET) (38.5%), clarithromycin (CLR) (34.4%), amoxicillin (AMX) (27.1%) and
furazolidone (FRZ) (23.9%). No significant difference was found between resistance of H. pylori isolates from male and female <40
and >40 years old and patients with gastritis and peptic ulcer. The highest rates of MDR were to MTZ+OFX (4.6%), MTZ+OFX+TET
(2.8%), MTZ+OFX+CIP+LVX (6.4%) and MTZ+OFX+TET+ CIP+LVX (5%).
Conclusion: Resistance to MTZ increased from 33%–55.6% in previous studies to 79.4% by time, to CLR increased from 1.4–7.3%
to 34.4%, to TET increased from 0–38.1% to 38.5%, to AMX increased from 1.4%–7.3% to 27.1% and to FRZ increased from
0%–4.5% to 23.9%. Resistance to FQs was 45%–58.7%. Increase in H. pylori antibiotic resistance indicates antibiotic misuse.
In Iran, with a considerable number of H. pylori- infected patients, antibiotic therapy should be saved for high risk patients and
according to local antibiotic resistance patterns.