Rapid detection of carbapenemase activity of Enterobacteriaceae isolated from positive blood cultures by MALDI-TOF MS

Peaks of ertapenem and their hydrolysed, decarboxylated form detected by MALDI-TOF MS. “ETP” means the peaks of ertapenem solution after 2 h incubation, “Positive” means the peaks of ertapenem solution after 2 h incubation with carbapenemase producers, “Negative” means the peaks of ertapenem solution after 2 h incubation with non-carbapenemase producer