Background: High resistance to common antibiotics has become a huge global dilemma
in eradicating Helicobacter Pylori infection in both children and adults. The great concern
is about the resistance to different classes of antibiotics especially Clarithromycin because of its
Objectives: The present survey aimed to assess the resistance rate to Clarithromycin in Helicobacter
Pylori isolated in patients aged less than 15 years as compared to patients older than 15 years
Methods: In this cross-sectional study, total 72 patients with upper gastrointestinal symptoms requiring
diagnostic endoscopy referred to Rasoul-e-Akram Hospital in Tehran during one year
(August 2015 to August 2016). Helicobacter Pylori infection was diagnosed in patients using the
Rapid Urease Test. The antibiotics resistance was detected in genomes using the real-time polymerase
chain reaction (PCR) on 23S rRNA gene.
Results: In total 72 patients, 36 cases aged less than or equal to 15 years and 36 patients were
older than 15 years. Of all patients in this study, 17 cases were detected with gene mutations or
polymorphisms related to resistance to Clarithromycin. Overall prevalence rate of resistance was
reported 23.61%. Three polymorphisms on 23S rRNA gene including A2142G, A2142C, and
A2143G were revealed in 47.1%, 5.9%, and 47.1% of patients, respectively. The bacterial resistance
to Clarithromycin was observed more prevalent in patients that aged older than 15 years
compared to patients younger than 15 years of age. Also, frequent consumption of any type of antibiotics
was significantly associated with the higher resistance of bacterium to Clarithromycin.
Conclusion: The results of our study regarding the resistance of Helicobacter Pylori to
Clarithromycin were similar to findings of other studies around the world. But, the Clarithromycin
resistance rate was reported higher in patients older than 15 years of age and those patients who
repeatedly received different types of antibiotics regardless of their age. Of all mutations in bacterial
genome, the prominent mutations responsible for bacterial resistance to Clarithromycin included
A2142C, A2142G, and A2143G nucleotide polymorphism on 23S rRNA gene.