Australian Group on Antimicrobial Resistance (AGAR) Australian Gram-negative Sepsis Outcome Programme(GNSOP) Annual...

The Australian Group on Antimicrobial Resistance (AGAR) performs regular period-prevalence studies to monitor changes in antimicrobial resistance in selected enteric Gram-negative pathogens. The 2015 survey was the third year to focus on blood stream infections, and included Enterobacteriaceae, Pseudomonas aeruginosa and Acinetobacter species. Seven thousand three hundred and thirty species, comprising Enterobacteriaceae (6,567, 89.6%), P. aeruginosa (660, 9.0%) and Acinetobacter species (103, 1.4%), were tested using commercial automated methods (Vitek® 2, BioMérieux; Phoenix™, BD) and results were analysed using Clinical and Laboratory Standards Institute (CLSI) and European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints (January 2016). Of the key resistances, non-susceptibility to the third-generation cephalosporin, ceftriaxone, was found in 10.6%/10.6% of E. coli (CLSI/EUCAST criteria) and 5.9%/5.9% of Klebsiella pneumoniae, and 8.4%/8.4% K. oxytoca. Non-susceptibility rates to ciprofloxacin were 12.6%/13.6% for E. coli, 3.9%/7.2% for K. pneumoniae, 0.4%/0.4% for K. oxytoca, 3.4%/4.0% for Enterobacter cloacae, and 6.3%/6.5% for Pseudomonas aeruginosa. Resistance rates to piperacillin-tazobactam were 2.8%/6.3%, 3.5%/6.4%, 8.9%/10.2%, 15.9%/20.6%, and 7.1%/13.9% for the same four species respectively. Twenty-two isolates were shown to harbour a carbapenemase gene, 14 blaIMP, four blaOXA-48, one blaKPC, one blaGES, one blaNDM+OXA-48, and one blaIMP+VIM.