The tigecycline evaluation and surveillance trial; assessment of the activity of tigecycline and other selected antibiotics against gram-positive and gram-negative pathogens from France collected between 2004 and 2016.

BACKGROUND

A high level of antibiotic consumption in France means antimicrobial resistance requires rigorous monitoring. The Tigecycline Evaluation and Surveillance Trial (T.E.S.T.) is a global surveillance study that monitors the in vitro activities of tigecycline and a panel of marketed antimicrobials against clinically important Gram-positive and Gram-negative isolates.

METHODS

Annually clinically relevant strains were prospectively included in the survey through a national network of hospital-based laboratories. MICs were determined locally by broth microdilution using CLSI guidelines. Antimicrobial susceptibility was assessed using European Committee on Antimicrobial Susceptibility Testing breakpoints.

RESULTS

Thirty-three centres in France collected 26,486 isolates between 2004 and 2016. species were highly susceptible (≥94.4%) to linezolid, tigecycline and vancomycin. , including methicillin-resistant (MRSA), were susceptible (≥99.9%) to tigecycline, vancomycin and linezolid. Between 2004 and 2016, 27.7% of isolates were MRSA, decreasing from 28.0% in 2013 to 23.5% in 2016. Susceptibility of isolates was 100% to vancomycin, and > 99.0% to levofloxacin, linezolid and meropenem; 3.0% were penicillin-resistant (100% susceptibility to vancomycin and linezolid). isolates were highly susceptible (> 98.0%) to meropenem, tigecycline and amikacin. The rate of extended-spectrum β-lactamase (ESBL) positive increased from 2004 (3.0%), but was stable from 2012 (23.1%) to 2016 (19.8%). Susceptibility of isolates was 99.4% to meropenem and 96.5% to amikacin. The proportion of ESBL-positive isolates increased from 2004 (7.5%) to 2012 (33.3%) and was highest in 2016 (43.6%). was susceptible to meropenem (81.0%) and amikacin (74.9%); none of the 6.2% of isolates identified as multidrug-resistant (MDR) was susceptible to any agents with breakpoints. isolates were most susceptible to amikacin (88.5%), and MDR rates were 13.6% in 2013 to 4.0% in 2016; susceptibility of MDR isolates was no higher than 31.4% to amikacin.

CONCLUSIONS

Rates of MRSA decreased slowly, while rates of ESBL-positive and increased from 2004 to 2016. Susceptibility of Gram-positive isolates to vancomycin, tigecycline, meropenem and linezolid was well conserved, as was susceptibility of Gram-negative isolates to tigecycline and meropenem. The spread of MDR non-fermentative isolates must be carefully monitored.