Naïma Raaf1,2, Wahiba Amhis2, Houria Saoula3, Ahmed Abid4, Mhamed Nakmouche3, Abdelmalek Balamane4, Nassima Ali Arous5, Mounira Ouar-Korichi6, Filipa F Vale7, Lucie Bénéjat8, Francis Mégraud8. 1. Département de Microbiologie, Faculté des Sciences de la Nature et de la Vie, Université Ferhat Abbas, Setif, Algeria. 2. Laboratoire Central de Biologie Clinique, EPH Ibn Ziri Bologhine, Algiers, Algeria. 3. Service de Gastroentérologie, CHU Lamine Debaghine Bab El Oued, Algiers, Algeria. 4. Service de Gastroentérologie, CHU Isaad Hassani Beni Messous, Algiers, Algeria. 5. Servive de Médecine interne, EPH Ibn Ziri Bologhine, Algiers, Algeria. 6. Laboratoire des Entérobactéries et autres bactéries apparentées, Institut Pasteur d'Algérie, Algiers, Algeria. 7. Host-Pathogen Interactions Unit, Research Institute for Medicines (iMed-ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Lisboa, Portugal. 8. French National Reference Center for Campylobacters and Helicobacters, Laboratoire de Bactériologie, Hôpital Pellegrin, & INSERM U 1053, Université de Bordeaux, Bordeaux, France.
Abstract
BACKGROUND: Helicobacter pylori infection is common in Algeria, but there are few data on the characterization of isolated strains. The aim of this study was to update data on the prevalence of H. pylori in patients submitted to endoscopy, antibiotic resistance, and phylogeography of H. pylori strains isolated in Algiers. MATERIALS AND METHODS: This is a prospective study carried out between November 2015 and August 2016. The culture of H. pylori was performed on antral and fundic gastric biopsies of adult patients from 3 hospitals. A real-time PCR using the fluorescence resonance energy transfer (FRET) principle for the detection of H. pylori followed by a melting curve analysis for the detection of mutations associated with resistance to clarithromycin was applied. Differentiation between antral and fundic isolates of the same patient was also determined by RAPD, and an MLST typing was performed for characterization of the phylogeographic group of H. pylori. RESULTS: By real-time PCR, the prevalence of H. pylori infection among the 147 patients included was 57%. Culture was positive in only 29% of the cases. Twenty-seven percent of patients had received H. pylori eradication treatment. The primary and secondary resistance rates to clarithromycin were 23% and 36%, respectively, and to metronidazole, 45% and 71%, respectively. Only one isolate was resistant to levofloxacin, and no resistance to amoxicillin, tetracycline, and rifampicin was detected. A double population was present in 14 patients. The MLST analysis classified the 42 H. pylori strains from 38 patients in 2 haplotypes: hpEurope (33) and hpNEAfrica (9). CONCLUSION: The prevalence of H. pylori remains high in Algeria but appears to be decreasing in recent years. High resistance to clarithromycin requires increased monitoring of the evolution of antibiotic resistance and adaptation of eradication therapy.
BACKGROUND:Helicobacter pyloriinfection is common in Algeria, but there are few data on the characterization of isolated strains. The aim of this study was to update data on the prevalence of H. pylori in patients submitted to endoscopy, antibiotic resistance, and phylogeography of H. pylori strains isolated in Algiers. MATERIALS AND METHODS: This is a prospective study carried out between November 2015 and August 2016. The culture of H. pylori was performed on antral and fundic gastric biopsies of adult patients from 3 hospitals. A real-time PCR using the fluorescence resonance energy transfer (FRET) principle for the detection of H. pylori followed by a melting curve analysis for the detection of mutations associated with resistance to clarithromycin was applied. Differentiation between antral and fundic isolates of the same patient was also determined by RAPD, and an MLST typing was performed for characterization of the phylogeographic group of H. pylori. RESULTS: By real-time PCR, the prevalence of H. pylori infection among the 147 patients included was 57%. Culture was positive in only 29% of the cases. Twenty-seven percent of patients had received H. pylori eradication treatment. The primary and secondary resistance rates to clarithromycin were 23% and 36%, respectively, and to metronidazole, 45% and 71%, respectively. Only one isolate was resistant to levofloxacin, and no resistance to amoxicillin, tetracycline, and rifampicin was detected. A double population was present in 14 patients. The MLST analysis classified the 42 H. pylori strains from 38 patients in 2 haplotypes: hpEurope (33) and hpNEAfrica (9). CONCLUSION: The prevalence of H. pylori remains high in Algeria but appears to be decreasing in recent years. High resistance to clarithromycin requires increased monitoring of the evolution of antibiotic resistance and adaptation of eradication therapy.