Helicobacter pylori Primary and Secondary Genotypic Resistance to Clarithromycin and Levofloxacin Detection in Stools: A 4-Year Scenario in Southern Italy

Abstract

Antibiotic resistance has become an emerging problem for treating Helicobacter pylori (H. pylori) infection. Clarithromycin and levofloxacin are two key antibiotics used for its eradication. Therefore, we reviewed our experience with genotypic resistance analysis in stools to both clarithromycin and levofloxacin in the last four years to evaluate time trends, both in naive and failure patients. Patients collected a fecal sample using the THD fecal test device. Real-time polymerase chain reaction was performed to detect point mutations conferring resistance to clarithromycin (A2142C, A2142G, and A2143G in 23S rRNA) and levofloxacin (substitutions at amino acid position 87 and 91 of gyrA). One hundred and thirty-five naive patients were recruited between 2017–2020. Clarithromycin resistance was detected in 37 (27.4%). The time trend did not show any significant variation from 2017 to 2020 (p = 0.33). Primary levofloxacin resistance was found in 26 subjects (19.2%), and we observed a dramatic increase in rates from 2017 (10%) to 2018 (3.3%), 2019 (20%), and 2020 (37.8%). Ninety-one patients with at least one eradication failure were recruited. Secondary resistance to clarithromycin and levofloxacin was found in 59 (64.8%) and 45 patients (59.3%), respectively. In conclusion, our geographic area has a high risk of resistance to clarithromycin. There is also a progressive spreading of levofloxacin-resistant strains.

Empiric “Three-in-One” Bismuth Quadruple Therapy for Second-Line Helicobacter pylori Eradication: An Intervention Study in Southern Italy

“…Despite our paper being similar to other studies in the literature, it is important to underline that the results of H. pylori eradication are strongly dependent on a “geographic factor”, i.e., the variability of the response according to different geographic distributions of antibiotic resistance [ 5 ]. Moreover, the changes in time and trends of antibiotic resistance may cause a decline in therapy effectiveness, therefore new studies that update the panorama of BQT are always important [ 31 ].…”

Management of Helicobacter pylori infection: Guidelines of the Italian Society of Gastroenterology (SIGE) and the Italian Society of Digestive Endoscopy (SIED)

“…The bismuth-based quadruple therapy is a complex 20-yearold regimen including PPI, bismuth, tetracycline, and metronidazole [64] . To overcome the complexity of this regimen, a new galenic formulation of the "3-in-1" capsule (Pylera®) is available in many European countries including Italy [66] .…”

Treatment Approach of Refractory Helicobacter pylori Infection: A Comprehensive Review

“… 7 Resistance to clarithromycin- and levofloxacin-based therapies has been reported to be between 5% and 25%. 12 - 14 …”

“…7 Resistance to clarithromycin-and levofloxacin-based therapies has been reported to be between 5% and 25%. [12][13][14] In this review article, we outline the approach to testing and treating patients with an initial H. pylori infection and refractory cases. We describe the evidence behind treatment recommendations and provide a glimpse of therapies under investigation.…”