Long-Term Continuous Antimicrobial Resistance Surveillance Among Nosocomial Gram-Negative Bacilli in China from 2010 to 2018 (CMSS).

PURPOSE

The Chinese Meropenem Surveillance Study (CMSS) was conducted every 2 years from 2010 to 2018 to monitor the antimicrobial activity of commonly used antimicrobial agents against nosocomial gram-negative bacilli in China.

METHODS

From 2010 to 2018, 6,537 gram-negative bacilli were collected from 14 teaching hospitals. The minimum inhibitory concentrations (MICs) of meropenem and other antimicrobial agents were determined using the agar dilution and broth microdilution methods.

RESULTS

Continuous surveillance indicated that, except for , the susceptibility of to carbapenems was relatively stable over time. Carbapenems had the highest activity against the tested isolates, with MIC values (MIC for 90% of organisms) ranging from 0.032 mg/L to 8 mg/L. More than 90% of bacteria were susceptible to either meropenem or imipenem; more than 80% were susceptible to ertapenem. The prevalence of extended-spectrum beta-lactamase (ESBL)-producing , and each year was 50.4-64.3%, 18-41.2%, and 1.9-33.8%, respectively. The prevalence of carbapenem-resistant (CRKP) and carbapenem-resistant (CRAB) continued to increase significantly over time, from 7.6% to 21.2% and 64.6% to 69.3%, respectively. The prevalence of CRKP was higher from urinary tract infections (25.4%) than from bloodstream infections (14.2%), intra-abdominal infections (14.5%), and respiratory infections (14.4%). In total, 129 CRKP isolates were evaluated by PCR; of these, 92 (71.3%) carried the gene. Colistin maintained very high in vitro antimicrobial activity against and (more than 95% of isolates exhibited susceptibility at all timepoints).

CONCLUSION

The results indicate an increase in resistance to carbapenems over time, mainly owing to KPC-type carbapenemase production. was severely resistant to carbapenems in China. Ongoing MIC-based resistance surveillance, like CMSS, provides additional data for clinical anti-infective treatment.