Are molecular methods helpful for the diagnosis of Helicobacter pylori infection and for the prediction of its antimicrobial resistance?

Abstract

Infections produced by Helicobacter pylori (H. pylori), a spiral Gram-negative bacterium, can cause chronic gastritis, peptic ulcer, and gastric cancer. Antibiotic therapy is the most effective treatment for H. pylori infection at present. However, owing to the increasing antibiotic resistance of H. pylori strains, it has become a serious threat to human health. Therefore, the accurate diagnosis of H. pylori infections and its antibiotic resistance markers is of great significance. Conventional microbiological diagnosis of H. pylori is based on culture; however, successful isolation of H. pylori from gastric biopsy specimens is a challenging task affected by several factors and has limitations in terms of the time of response. To improve conventional methods, some molecular techniques, such as PCR, have been recently used in both invasive and non-invasive H. pylori diagnosis, enabling simultaneous detection of H. pylori and point mutations responsible for frequent antibiotic resistance. The advantages and disadvantages of molecular methods, mainly PCR, versus conventional culture for the H. pylori identification and the detection of antibiotic resistance are discussed. As expected, the combination of both diagnostic methods will lead to the most efficient identification of the H. pylori strains and the resistance patterns.

Tailored therapy guided by genotypic resistance of clarithromycin and levofloxacin detected by polymerase chain reaction in the first‐line treatment of Helicobacter pylori infection

“…With the development of genetic testing and an in-depth understanding of the mechanisms involved in antibiotic resistance, polymerase chain reaction (PCR) that can detect mutation sites of antibiotic resistance genes has emerged in recent years, using which the information of genotypic resistance can be quickly, easily, and accurately obtained to facilitate tailored eradication therapy of H. pylori infection. [10][11][12] Genotypic resistance of clarithromycin and levofloxacin has shown good agreement with their phenotypic resistance, which may be promising and clinically feasible testing targets for tailored therapy of H. pylori infection. 13,14 There have been a limited number of studies on the genotypic resistance of clarithromycin and levofloxacin to guide therapy.…”

“…Therefore, it is primarily used for patients with refractory H. pylori infection who have failed multiple eradication attempts and are unsuitable for first‐line treatments. With the development of genetic testing and an in‐depth understanding of the mechanisms involved in antibiotic resistance, polymerase chain reaction (PCR) that can detect mutation sites of antibiotic resistance genes has emerged in recent years, using which the information of genotypic resistance can be quickly, easily, and accurately obtained to facilitate tailored eradication therapy of H. pylori infection 10–12 . Genotypic resistance of clarithromycin and levofloxacin has shown good agreement with their phenotypic resistance, which may be promising and clinically feasible testing targets for tailored therapy of H. pylori infection 13,14 …”

Drug-Resistant Helicobacter pylori: Diagnosis and Evidence-Based Approach

“…Molecular-based methods have emerged as a more rapid (up to <4 h), cost-effective, and highly reproducible alternative to culture-based methods for detecting H. pylori and determining its resistance, given the challenges associated with traditional culture methods. Molecular methods can detect heteroresistant infections and are less affected by the modulation of bacterial burden caused by the recent use of PPIs [ 23 , 24 , 40 , 41 ]. Recent large RCTs have demonstrated that molecular testing-guided therapy is comparable to culture-based susceptibility testing-guided therapy in first-line therapy and non-inferior to the latter in third-line treatment of H. pylori infection, thereby supporting the use of molecular testing-guided therapy for H. pylori eradication [ 42 ].…”

“…The observed correlation between the utilization of RUT gastric biopsies for molecular testing after 30 days at room temperature was 93% [ 43 ]. In addition, these methods allow for the non-invasive detection of antibiotic resistance [ 40 ]. Gastric contents (i.e., gastric fluid, mucus, or mucosal biopsies), formalin-fixed, paraffin-embedded (FFPE) tissue, stools, or repurposed tissue from histology or rapid urease tests can be used for testing.…”

New recording genes and genetic mutations of H. pylori genome in gastroduodenal disease patients in Basrah province-Iraq

“…Results of this study show the relationship between the studied virulence genes with predisposition and risks of gastroduodenal diseases. The identification of H. pylori-specific gene region by using molecular techniques such as PCR is faster than culture since H. pylori culturing requires 10-14 days to be confirmed (9). Sulo and Sipkova, (2021) reported that conventional PCR was more reliable than histology to confirm positive results (10).…”