European surveillance of antimicrobial resistance in Neisseria gonorrhoeae.

OBJECTIVE: To perform a European sentinel surveillance study for antimicrobial resistance (AMR) in Neisseria gonorrhoeae as part of the European Surveillance of Sexually Transmitted Infections Programme. METHODS: From 2006 to 2008 17 countries participated in the AMR surveillance programme. The susceptibility of a total of 3528 consecutive isolates was tested using the agar dilution breakpoint technique or Etests for ciprofloxacin, penicillin, tetracycline, azithromycin, spectinomycin and ceftriaxone. Nitrocefin was used to detect ß-lactamase activity. RESULTS: Rates of resistance to ciprofloxacin, the previously recommended treatment, were high across Europe (42-52%), indicating that usage is no longer appropriate. Although resistance to the currently recommended treatment, ceftriaxone, was not demonstrated, a concerning upward drift in the minimal inhibitory concentration (MIC) distribution was identified since an earlier European study in 2004. No resistance to spectinomycin was seen, whereas azithromycin resistance varied from 2% to 7% and isolates from Scotland (n=4) and Ireland (n=1) showed high-level resistance (MIC >256 mg/l). High-level resistance to tetracycline and penicillin remained relatively constant at 16% and 12%, respectively. CONCLUSIONS: AMR is an ongoing problem in Europe, with high rates of resistance to many previously recommended therapeutic agents observed in many European countries. Continual European and global surveillance of AMR in N gonorrhoeae is essential to monitor for increasing, emerging and high-level resistance to therapeutically relevant agents and to inform treatment guidelines so optimum treatments are administered.

Amoxicillin therapy of poultry flocks: effect upon the selection of amoxicillin-resistant commensal Campylobacter spp.

BACKGROUND: The aim of this study was to investigate the effect of amoxicillin therapy of poultry flocks upon the persistence of commensal Campylobacter spp. and the incidence of antibiotic resistance. METHODS: Four poultry flocks naturally colonized with Campylobacter were treated with amoxicillin and monitored before, during and up to 4 weeks post-treatment. The numbers of Campylobacter were determined and the isolates speciated and typed by flaA short variable region (SVR) sequence analysis and PFGE. The susceptibility of the isolates to antibiotics, presence of the Cj0299 gene encoding a beta-lactamase and beta-lactamase production (nitrocefin hydrolysis) were also determined. RESULTS: Amoxicillin-resistant Campylobacter were isolated from Flock 1 before and during treatment, but Campylobacter were not detected afterwards. Flock 2 was colonized by amoxicillin-susceptible strains throughout sampling. No amoxicillin-resistant isolates arose during or after treatment. Flock 3 contained amoxicillin-susceptible and -resistant types pre-treatment. Resistant isolates were detected during treatment, while antibiotic-susceptible isolates re-emerged at 3 weeks post-treatment. All Campylobacter isolates from Flock 4 were amoxicillin resistant, irrespective of sampling time. All but one of the 82 amoxicillin-resistant (MICs 16 to >128 mg/L) Campylobacter jejuni and Campylobacter coli tested for the presence of Cj0299 carried the gene and all of these produced beta-lactamase. Co-amoxiclav remained active against amoxicillin-resistant isolates. CONCLUSIONS: Amoxicillin therapy had little effect on the numbers of amoxicillin-resistant commensal Campylobacter except for one flock where amoxicillin-resistant Campylobacter temporarily dominated. Amoxicillin therapy did not select amoxicillin-resistant isolates from a previous susceptible strain. Co-amoxiclav remained active against amoxicillin-resistant isolates.