Characterization of Antimicrobial Resistance Patterns and Detection of Virulence Genes in Campylobacter Isolates in Italy

Abstract

Campylobacter has developed resistance to several antimicrobial agents over the years, including macrolides, quinolones and fluoroquinolones, becoming a significant public health hazard. A total of 145 strains derived from raw milk, chicken faeces, chicken carcasses, cattle faeces and human faeces collected from various Italian regions, were screened for antimicrobial susceptibility, molecular characterization (SmaI pulsed-field gel electrophoresis) and detection of virulence genes (sequencing and DNA microarray analysis). The prevalence of C. jejuni and C. coli was 62.75% and 37.24% respectively. Antimicrobial susceptibility revealed a high level of resistance for ciprofloxacin (62.76%), tetracycline (55.86%) and nalidixic acid (55.17%). Genotyping of Campylobacter isolates using PFGE revealed a total of 86 unique SmaI patterns. Virulence gene profiles were determined using a new microbial diagnostic microarray composed of 70-mer oligonucleotide probes targeting genes implicated in Campylobacter pathogenicity. Correspondence between PFGE and microarray clusters was observed. Comparisons of PFGE and virulence profiles reflected the high genetic diversity of the strains examined, leading us to speculate different degrees of pathogenicity inside Campylobacter populations.

Antimicrobial susceptibility profile of Campylobacter spp. isolated from different animal species in Minas Gerais

“…The increase in resistance rates to tetracyclines of Campylobacter spp. is worrisome and has been constantly described, mainly in animal isolates (GALLAY et al, 2007;SAHIN et al, 2008;CHEN et al, 2010;LEHTOPOLKU et al, 2010;ADZITEY et al, 2012;CHOKBOONMONGKOL et al, 2013;DI GIANNATALE et al, 2014). Resistance to tetracycline has a clinical importance, since tetracycline is considered a second-line treatment for human Campylobacter spp.…”

“…isolates, from both humans and animals, to different classes of antimicrobial agents such as quinolones, macrolides, aminoglycosides, tetracyclines, β-lactams, and sulfonamides has been widely reported ( VAN DEN BOGAARD;STOBBERINGH, 2000;CHUMA et al, 2001;AVRAIN et al, 2003;TREMBLAY et al, 2003;MIRANDA;LAGE, 2007;ABAY et al, 2014;DI GIANNATALE et al, 2014). Nonetheless, mainly the resistance to quinolones and macrolides has been considered an emerging public health hazard, due to its fast increase in the last decades (GIBREEL; TAYLOR, 2006;FITZGERALD et al, 2008;GARCIA-MIGURA et al, 2014).…”

Virulence genes and cytokine profile in systemic murineCampylobacter coliinfection

“…29 More specifically considering the virulence mechanisms for the pathogenesis of Campylobacter spp. during human infections, these might contribute to their flagella-mediated motility, adherence to the intestinal mucosa, invasive capability, and production of toxins.…”

Scientific Opinion on the public health risks related to the consumption of raw drinking milk

“…In particular, the presence of C. jejuni in in-line milk filters and raw milk confirmed that raw milk consumption is a significant risk factor for human infection in Italy. Further studies have indicated a significant level of resistance to ciprofloxacin (62.8 %), tetracyclines (55.9 %) and nalidixic acid (55.2 %) in isolates of C. jejuni from a variety of animal-related sources, including raw milk, and also from human faeces, although the precise sources of such strains are not provided (Di Giannatale et al, 2014). Outside the EU, in a study in Quebec, Canada, of C. jejuni isolates obtained between 2000 and 2003 from a variety of sources, which included 33 isolates from raw milk, ciprofloxacin resistance was reported to be almost absent in isolates from water, chicken, and raw milk (Levesque et al, 2007).…”