{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T17:36:00Z","timestamp":1791308160184,"version":"4.3.1"},"reference-count":45,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2024,10,1]],"date-time":"2024-10-01T00:00:00Z","timestamp":1727740800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Science, Technological Development and Innovation of the Republic of Serbia","award":["451-03-66\/2024-03\/200110"],"award-info":[{"award-number":["451-03-66\/2024-03\/200110"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Background\/Objectives: Stomach infections by Helicobacter pylori can cause acute or chronic gastritis, peptic ulcers, and gastric cancer. The rise in antibiotic resistance is a significant health issue highlighted by the World Health Organization. The increasing number of treatment failures underscores the necessity for antibiotic susceptibility testing (AST). The study aimed to investigate the current prevalence and resistance to fluoroquinolones and clarithromycin with their detected mutations. Methods: Stomach biopsies from symptomatic patients were subjected to molecular testing by GenoType Helico DR kit (Hain Lifescience GmbH, Nehren, Germany). Results: Positive findings on the presence of H. pylori were detected in 42.4% of symptomatic patients, with the significant majority of patients (69%) having previously failed treatments. The resistance rates to fluoroquinolones and clarithromycin were 53.9% and 58.5%, respectively, with significantly higher rates in secondary resistant strains. The main resistance markers in fluoroquinolones and clarithromycin were N87K (27.4%) and A2147G (78.6%), respectively. Hetero-resistance or mixed genotypes were detected in over 20% of tested patients. During the study period, a significant increase in trends in both fluoroquinolones and clarithromycin resistance rates was observed. Conclusions: Results indicate the need for the implementation of the latest Maastricht VI Consensus recommendations for both AST whenever possible and the use of tailored guided therapy options due to high resistance rates and possible treatment failures. The GenoType Helico DR kit is a useful tool for AST, especially in cases of mixed H. pylori genotypes.<\/jats:p>","DOI":"10.3390\/antibiotics13100933","type":"journal-article","created":{"date-parts":[[2024,10,1]],"date-time":"2024-10-01T05:26:33Z","timestamp":1727760393000},"page":"933","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Genetic Determinants of Clarithromycin and Fluoroquinolones Resistance in Helicobacter pylori in Serbia"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0327-4838","authenticated-orcid":false,"given":"Dusan","family":"Kekic","sequence":"first","affiliation":[{"name":"Institute for Microbiology and Immunology, Faculty of Medicine, University of Belgrade, 11 000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Milos","family":"Jovicevic","sequence":"additional","affiliation":[{"name":"Institute for Microbiology and Immunology, Faculty of Medicine, University of Belgrade, 11 000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3727-6583","authenticated-orcid":false,"given":"Jovana","family":"Kabic","sequence":"additional","affiliation":[{"name":"Institute for Microbiology and Immunology, Faculty of Medicine, University of Belgrade, 11 000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7565-4584","authenticated-orcid":false,"given":"Iva","family":"Lolic","sequence":"additional","affiliation":[{"name":"Emergency Center, University Clinical Center of Serbia, 11 000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1578-2776","authenticated-orcid":false,"given":"Ina","family":"Gajic","sequence":"additional","affiliation":[{"name":"Institute for Microbiology and Immunology, Faculty of Medicine, University of Belgrade, 11 000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2256-7513","authenticated-orcid":false,"given":"Stefan","family":"Stojkovic","sequence":"additional","affiliation":[{"name":"Clinic for Gastroenterology and Hepatology, University Clinical Centre of Serbia, 11 000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lazar","family":"Ranin","sequence":"additional","affiliation":[{"name":"Institute for Microbiology and Immunology, Faculty of Medicine, University of Belgrade, 11 000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4396-7532","authenticated-orcid":false,"given":"Tomica","family":"Milosavljevic","sequence":"additional","affiliation":[{"name":"Euromedic, General Hospital, 11 000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8765-4044","authenticated-orcid":false,"given":"Natasa","family":"Opavski","sequence":"additional","affiliation":[{"name":"Institute for Microbiology and Immunology, Faculty of Medicine, University of Belgrade, 11 000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5767-3914","authenticated-orcid":false,"given":"Ivan","family":"Rankovic","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Liver Care, Royal Cornwall Hospitals NHS Trust University of Exeter, Treliske, Truro, Cornwall TR1 3LQ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3601-7528","authenticated-orcid":false,"given":"Vladimir","family":"Milivojevic","sequence":"additional","affiliation":[{"name":"Clinic for Gastroenterology and Hepatology, University Clinical Centre of Serbia, 11 000 Belgrade, Serbia"},{"name":"Faculty of Medicine, University of Belgrade, 11 000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1698","DOI":"10.1007\/s10620-014-3063-0","article-title":"Prevalence of Helicobacter pylori infection worldwide: A systematic review of studies with national coverage","volume":"59","author":"Peleteiro","year":"2014","journal-title":"Dig. 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