Evaluation of MALDI-TOF mass spectrometry (VITEK-MS) compared to the ANC card (VITEK 2) for the identification of clinically significant anaerobes

• Autor(a) principal: Tsukimoto,Eliane R.
• Data de Publicação: 2018
• Outros Autores: Rossi,Flávia
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Jornal Brasileiro de Patologia e Medicina Laboratorial (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1676-24442018000400206
• topic: matrix assisted laser desorption ionization-time of flight mass spectrometry; clinical laboratory techniques; bacteroides infections; anaerobic bacteria; Clostridium infections

ABSTRACT Introduction: The identification of anaerobic bacteria by conventional methods employed in clinical laboratories requires a lot of work and a long response time [turnaround time (TAT)]. Matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is an accurate, rapid and inexpensive technique with promising results for bacterial identification. Objective: To evaluate the MALDI-TOF mass spectrometry (VITEK-MS, bioMérieux, France) compared to the ANC card (VITEK 2, bioMérieux, France) for the identification of anaerobes, and also veriying the cost variation between both methodologies. Methods: 421 anaerobes were concomitantly identified by ANC (VITEK 2) and MALDI-TOF (VITEK MS). The conflicting results or those presenting low differentiation of the species were subjected to the 16S ribosomal ribonucleic acid (rRNA) sequencing. Results: Thirty-five strains were not identified by ANC (VITEK 2), and only one isolate was not identified by MALDI-TOF (VITEK MS). From the 386 anaerobes identified by the two methodologies, 97% agreement was observed on the identification of genus and species between the methodologies. Thirteen (3%) isolates were submitted to 16S sequencing. The agreement observed was 70% using ANC (VITEK 2) using 92% by MALDI-TOF (VITEK MS). Conclusion: Both methodologies showed an excellent performance for the identification of the strains tested with great differences in relation to cost-benefit. MALDI-TOF MS allowed 35 additional identifications and a saving of BRL$ 7,786 with the release of culture positive result five days ahead of the ANC (VITEK 2). TAT reduction may contribute to a successful clinical resolution.