Épidémiologie de la résistance aux antibiotiques chez les entérocoques en France

Since the mid-70s, enterococci have become one of the major causes of nosocomial infection. Enterococcus faecalis isolates remain susceptible to ampicillin. The prevalence of high-level resistance to gentamicin is stable around 15 %. Resistance to vancomycin is rare and detected in only 0.2 % of isolates from blood cultures. However, co-resistance to gentamicin is recently increasing (55 %) and the few isolates responsible for outbreaks have been reported as belonging to the CC2 clonal complex. The most worrying enterococcal outbreaks are due to Enterococcus faecium strains that belong to the clonal complex CC17 spreading worldwide. These hospital-adapted clones accumulate ampicillin-, fluoroquinolone-, vancomycin- and high-level resistance to gentamicin. In France, less than 2 % of E. faecium isolated from blood cultures are resistant to vancomycin (71 % with the VanA phenotype). Vancomycin-resistant E. faecium isolates are significantly more resistant to ampicillin (95 % versus 50 % of vancomycin-susceptible isolates), lincomycin (98 % versus 57.5 %) and erythromycin (96 % versus 88.5 %). Noteworthy, a high proportion of VRE isolates is also levofloxacin- and cotrimoxazole-resistant, but remain susceptible to linezolid, rifampin, fusidic acid and tigecycline. Spread of particularly epidemic and multiresistant E. faecium and to a less extent E. faecalis isolates, deserves prospective surveillance.