Epidemiologic cutoff values to separate wild-type from non-wild-type Campylobacter fetus to ciprofloxacin.

The aim of the present study was to propose epidemiologic cutoffs that could be used in routine practice to separate wild-type from non-wild-type Campylobacter fetus to ciprofloxacin. A total of 123 C. fetus isolates obtained from human samples were used for this purpose. Based on the determination of inhibition zone diameter, minimum inhibitory concentration, and sequencing of the quinolone resistance determining region in the gyraseA gene, for all tested isolates, the following cutoffs were proposed: ciprofloxacin-wild type if the inhibition zone diameter was ≥22 mm or the minimum inhibitory concentration was ≤0.5 mg/L.

Helicobacter pylori resistance to antibiotics in 2014 in France detected by phenotypic and genotypic methods.

A large survey of antimicrobial resistance of Helicobacter pylori was performed in France in 2014: 984 patients were enrolled by 75 gastroenterologists all over the country. Among the 783 patients who had never received eradication treatment before, 266 (33.9%) were H. pylori positive. The strains showed a high rate of clarithromycin resistance (22.2%), moderate rate of resistance to levofloxacin (15.4%) and high rate of resistance to metronidazole (45.9%). In all, 187 patients had received previous treatment, of which 115 were H. pylori positive with very high resistance to clarithromycin (73.9%) and metronidazole (78.3%). None of the patients receiving PYLERA (Bismuth salt-Tetracycline HCl-Metronidazole) proton-pump inhibitor developed resistance to tetracycline. A real-time PCR applied to gastric biopsy specimens detected all the cases that were positive by culture as well as 30 additional cases. A good correlation was found between the clarithromycin resistance detected by phenotypic methods and the associated mutations for clarithromycin resistance, which has continued to increase in the last decade but at a lower rate than previously observed.

Characterization of a Campylobacter fetus-like strain isolated from the faeces of a sick leopard tortoise (Stigmochelys pardalis) using matrix-assisted laser desorption/ionization time of flight as an alternative to bacterial 16S rDNA phylogeny.

UNLABELLED: This article describes the isolation and characterization of a Campylobacter-like isolate originating from the faeces of a sick leopard tortoise. Molecular as well as matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) characterization suggests that it could correspond to a new Campylobacter species. SIGNIFICANCE AND IMPACT OF THE STUDY: The major impact of this work is the demonstration that proteomics and especially MALDI-TOF typing can be used as an alternative method to 16S rDNA sequencing for phylogeny and can lead to the discovery of new Campylobacters.

Identification of Campylobacter species and related organisms by matrix assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry.

The identification of Campylobacter species and related organisms at the species level has always been difficult using phenotypic methods because of their low metabolic activity, whereas molecular methods are more reliable but time-consuming. In this study, 1007 different strains were identified using three different methods: conventional methods, molecular biology (real-time PCR and sequencing) and matrix assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. Molecular methods were considered the gold standard. The accuracy of MALDI-TOF mass spectrometry reached 100% compared with the gold standard for all of the Campylobacter species, except Campylobacter jejuni (99.4%). The accuracy of conventional methods compared with the gold standard ranged from 0% to 100% depending on the species. However, MALDI-TOF mass spectrometry was not able to identify a mixture of two different species present in the same sample in four instances. Finally, MALDI-TOF mass spectrometry is highly recommended to identify Campylobacter spp. as only 0.4% discrepancy was found, whereas conventional methods led to 4.5% discrepancy.