An improved protocol for bacteria identification by MALDI-TOF MS directly from positive blood cultures
Sara Santos Cruz, David Abreu, Rosário Gomes, Inês Martins-Oliveira, Ana Silva-Dias, Blanca Pérez-Viso, Rafael Cantón, Cidália Pina‐Vaz
Abstract
FASTinov® developed a rapid antimicrobial susceptibility test that includes the purification of a bacterial suspension directly from positive blood cultures (BC). In order to streamline laboratory workflow, the use of the bacterial suspension obtained through FASTinov® sample prep was tested for identification (ID) by matrix absorption laser deionization-time of flight mass spectrometry (MALDI-TOF MS) (Bruker) in 364 positive BC, and its accuracy assessed comparing with the MALDI-TOF MS ID of the next-day subcultured colonies. FASTinov sample prep was highly reliable for rapid ID directly from BC with proportion of agreement of 94.9% for Gram-positive and 96.3% for Gram-negative bacteria.