Primary antibiotic resistance of Helicobacter pylori strains isolated from patients with dyspeptic symptoms in Beijing: A prospective serial study

AIM:To determine the resistance patterns of Helicobacter pylori(H.pylori) strains isolated from patients in Beijing and monitor the change of antibiotic resistance over time.METHODS:In this prospective,serial and crosssectional study,H.pylori cultures were successfully obtained from 371 and 950 patients(never receiving eradication) during 2009-2010 and 2013-2014,respectively.Resistance to amoxicillin,clarithromycin,metronidazole,levofloxacin,tetracycline,and rifampicin was determined by Epsilometer test.RESULTS:The resistance rates of isolates obtained during 2009-2010 were 66.8%,39.9%,34.5%,15.4%,6.7%,and 4.9% to metronidazole,clarithromycin,levofloxacin,rifampicin,amoxicillin and tetracycline,respectively; and the corresponding rates for isolates during 2013-2014 were 63.4%,52.6%,54.8%,18.2%,4.4% and 7.3%,respectively.The resistance rates to clarithromycin and levofloxacin were significantly increased after four years.In 2009-2010,14.6% of H.pylori isolates were susceptible to all tested antibiotics,with mono(33.7%),double(28.3%),triple(16.7%),quadruple(6.2%),quintuple(0.3%) and sextuple resistance(0.3%) also being detected.In 2013-2014,9.4% were susceptible to all tested antibiotics,and mono(27.6%),double(28.4%),triple(24.9%),quadruple(7.3%),quintuple(2.3%) and sextuple resistance(0.1%) was also observed.More multiple resistant H.pylori isolates were found during 2013-2014.Gender(to levofloxacin and metronidazole),age(to levofloxacin) and endoscopic findings(to clarithromycin) were independent factors influencing antibiotic resistance.CONCLUSION:H.pylori resistance to commonly used antibiotics in Beijing is high with increased multiple antibiotic resistance.