Detection of carbapenemase activity in Pseudomonas aeruginosa by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS)

Abstract A new MALDI-TOF MS imipenem hydrolysis assay was developed to optimize detection of carbapenemase-producing strains of Pseudomonas aeruginosa . The method correctly discriminated carbapenemase producers ( n  = 74) from non-producers ( n  = 95) in 99.4% of cases, and successfully detected 100% GES-5 strains ( n  = 5).