RESUMO
The accuracy of matrix-assisted laser desorption-ionization time of flight mass spectrometry (MALDI-TOF MS) in the identification of Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, and Kingella (HACEK) species was compared to that of phenotypic methods (Remel RapID and Vitek 2). Overall, Vitek MS correctly identified more isolates, incorrectly identified fewer isolates, and failed to identify fewer isolates than both phenotypic methods.
Assuntos
Técnicas Bacteriológicas/métodos , Infecções por Bactérias Gram-Negativas/microbiologia , Neisseriaceae/isolamento & purificação , Pasteurellaceae/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Cardiobacterium/química , Cardiobacterium/classificação , Cardiobacterium/isolamento & purificação , Humanos , Neisseriaceae/química , Neisseriaceae/classificação , Pasteurellaceae/química , Pasteurellaceae/classificação , PediatriaRESUMO
Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry is a rapid and accurate tool for the identification of many microorganisms. We assessed this technology for the identification of 103 Haemophilus parainfluenzae, Aggregatibacter aphrophilus, Aggregatibacter actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae (HACEK) clinical isolates and 20 Haemophilus influenzae clinical isolates. Ninety-three percent of HACEK organisms were identified correctly to the genus level using the Bruker database, and 100% were identified to the genus level using a custom database that included clinical isolates.
Assuntos
Técnicas Bacteriológicas/métodos , Cardiobacterium/química , Eikenella corrodens/química , Haemophilus/química , Kingella kingae/química , Pasteurellaceae/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Cardiobacterium/classificação , Eikenella corrodens/classificação , Haemophilus/classificação , Humanos , Kingella kingae/classificação , Pasteurellaceae/classificação , Sensibilidade e EspecificidadeRESUMO
Samples from cardiac valves of 31 patients were analyzed by gas chromatography and mass spectrometry. The algorithm of mass spectrometric parameters was developed, which permitted the determination of about 200 known microbial fatty acids, aldehydes and sterols, sufficient for the detection and quantitative determination of more that 170 taxons of clinically significant microorganisms on the genus or species levels. The quantitative and qualitative differences in the composition of microbial markers of endocardial valves in normal and pathological states, particularly in cases of infectious endocarditis, were detected. The participation of 37 microbial taxons in the process was confirmed. The level of endocardium colonization in infectious endocarditis reached from 2 to 7 x 10(9) microbial cells/g of valvular tissue (which exceeded twofold the equivalent concentrations of the marker in the normal state). In terms of quantity, the leading role was played by Cardiobacterium hominis.
