Research On Probiotic-Assisted Genotypic Resistance Guided Therapy In Refractory Helicobacter Pylori Infection

Objective:To analyze the incidence of spherical transformation,the polymorphism of cytochrome P450 isoenzyme 2C19(CYP2C19)gene of acid suppressant drugs,drug resistance,and the mutation of antibiotic-related drug resistance genes in patients with refractory Helicobacter pylori infection,speculate the reason why Hp is difficult to be treated,and further improve the Hp resistance epidemiology in this region.To develop individualized eradication programs for patients with refractory Helicobacter pylori infection.To evaluate the feasibility of fluorescent quantitative PCR method instead of traditional drug sensitivity test to detect the resistance of Hp to amoxicillin,levofloxacin,furazolidone,clarithromycin,tetracycline and metronidazole.To evaluate the safety and efficacy of probiotic-assisted bismuth-containing quadruple regimen compared with conventional quadruple regimen.Methods:Prospective observational cohort study.Sixty patients with refractory Helicobacter pylori infection admitted to the multidisciplinary joint clinic of our hospital from January 2021 to December 2022 were selected and randomly divided into individualized treatment group(20cases),improved individualized treatment group(20 cases)and conventional empirical treatment group(20 cases).(1)The individualized treatment group received gastroscopy biopsy,Hp culture,pathological staining and immunohistochemistry to observe the occurrence of spherical Hp,disk diffusion method to detect the sensitivity of 6 antibiotics.The polymorphism of host CYP2C19 gene and the mutation sites of antibiotic resistance genes were detected by PCR combined with Taqman fluorescence probe technique.According to the results of drug sensitivity and gene detection,the consistency of two drug resistance detection methods was evaluated,and individualized eradication program was developed with probiotics.(2)The modified empiric treatment group was empirically treated with bismuth-containing quadruple regimen supplemented with probiotics;(3)The conventional empiric treatment group was empirically given a quadruple regimen containing bismuth.Medication,eradication results,incidence of adverse reactions and symptom relief were followed up in all three groups.Results:A total of 20 patients with refractory Hp infection were included in the individualized treatment group,among which 10 patients had spherical Hp changes in different proportions,among which 6 patients had about 5% spherical Hp,2 patients had about 20% spherical Hp,and2 patients had occasional spherical Hp.CYP2C19 genotype: 13 cases(65%)were fast metabolizers,7 cases(35%)were medium metabolizers,and no slow metabolizers were detected.The results of drug sensitivity showed that 14 cases(70%)were resistant to clarithromycin,20 cases(100%)were resistant to metronidazole,19 cases(95%)were resistant to levofloxacin,and no resistance was found to tetracycline,furazolidone and amoxicillin.Multiple drug resistance: Among 20 patients in the individualized treatment group,14 patients(70%)had triple drug resistance to clarithromycin,Levofloxacin and metronidazole,and 5patients(25%)had double drug resistance to levofloxacin and metronidazole.The mutation rates of metronidazole,clarithromycin,levofloxacin,furazolidone,tetracycline and amoxicillin resistance genes were 100.0%,100.0%,95.0%,95.0%,30.0% and 100.0%,respectively.In addition to the low consistency of clarithromycin resistance gene mutation and drug sensitivity test results,sensitivity: 70%(14/20),the remaining 5 antibiotics and two drug resistance test results,high consistency: 100%(20/20).The eradication rates of ITT and PP in the three groups were as follows: individualized treatment group: 95%,95%;Improved experiential treatment group: 70%,82.35%;Conventional empiric treatment group: 60%,80%.The incidence of adverse reactions in the three groups were as follows: individualized treatment group: 2cases(10%);Modified empiric therapy group: 4 cases(20%);Conventional empiric therapy group: 4 cases(20%).The effective rates of symptom improvement were 88.24% and 80.0% in the modified empiric treatment group and the conventional empiric treatment group,respectively,and the difference was statistically significant(P < 0.05).Conclusion:The main reason for the failure of eradication of refractory Helicobacter pylori is multiple antibiotic resistance,followed by CYP2C19 gene polymorphism,and Hp sphericity may be the potential cause of individualized treatment failure.The drug resistance rate of amoxicillin,furazolidone and tetracycline was significantly lower than that of other antibacterial drugs.For RHPI patients,genotypic resistance guided therapy is a more effective eradication regimen than empirical remedial therapy.Probiotics can reduce the occurrence of adverse reactions and improve the eradication rate in the bismuth-containing quadruple regimen,which is worth promoting.