Direct matrix-assisted laser desorption ionization time-of-flight mass spectrometry and real-time PCR in a combined protocol for diagnosis of bloodstream infections: a turnaround time approach

Publication date: Available online 5 June 2019Source: The Brazilian Journal of Infectious DiseasesAuthor(s): Milene Gonçalves Quiles, Bruno Cruz Boettger, Fernanda Matsiko Inoue, Jussimara Monteiro, Daniel Wagner Santos, Vinicius Ponzio, Fabianne Carlesse, Paola Cappellano, Cecilia Godoy Carvalhaes, Antonio Carlos Campos PignatariAbstractBloodstream infections (BSIs) are serious infections associated with high rates of morbidity and mortality. Every hour delay in initiation of an effective antibiotic increases mortality due to sepsis by 7%. Turnaround time (TAT) for conventional blood cultures takes 48 h, forcing physicians to streamline therapy by exposing patients to broad-spectrum antimicrobials. Our objective was (1) to evaluate the accuracy and TAT of an optimized workflow combining direct matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and in-house real-time PCR for bacterial identification and antimicrobial resistance profiling directly from positive blood bottles for diagnosing bloodstream infections and (2) to verify the effect of reporting results to medical staff. A total of 103 BSI episodes from 91 patients admitted to three hospitals in São Paulo, Brazil were included. TAT from molecular versus conventional methods was measured and compared. Our protocol showed an overall agreement of 93.5% for genus and 78.5% for species identification; 74.2% for methicillin resistance detection, 89.2% for extended-spectrum β-l...
Source: The Brazilian Journal of Infectious Diseases - Category: Infectious Diseases Source Type: research