Table 2.
Microbial identification by LCM/MALDI-TOF versus classical ID/VITEK2 from OXOID SIGNAL BLOOD bottles
| Microorganism | Number of isolates analyzed | Correct id VITEK2 | Correct id MALDI-TOFa | No id MALDI-TOFb | Id genusc | Misidentified |
|---|---|---|---|---|---|---|
| Gram positive | 16 | 16 | 12 | 2 | 1 | 1 |
| Enterococcus faecalis | 4 | 4 | 3 | 1 | – | – |
| Enterococcus faecium | 2 | 2 | 2 | – | – | – |
| Staphylococcus epidermidis | 3 | 3 | 3 | – | – | – |
| Staphylococcus aureus | 3 | 3 | 3 | – | – | – |
| Streptococcus pyogenes | 1 | 1 | 1 | – | – | – |
| Streptococcus mitis | 1 | 1 | – | 1 | – | – |
| Streptococcus mutans | 1 | 1 | – | – | – | 1d |
| Streptococcus parasanguinis | 1 | 1 | – | – | 1 | – |
| Gram negative | 25 | 25 | 25 | – | – | – |
| Escherichia coli | 7 | 7 | 7 | – | – | – |
| Klebsiella pneumoniae | 9 | 9 | 9 | – | – | – |
| Achromobacter xylosoxidans | 1 | 1 | 1 | – | – | – |
| Proteus mirabilis | 1 | 1 | 1 | – | – | – |
| Pseudomonas aeruginosa | 4 | 4 | 4 | – | – | – |
| Acinetobacter lwoffii | 1 | 1 | 1 | – | – | – |
| Klebsiella oxytoca | 1 | 1 | 1 | – | – | – |
| Enterobacter cloacae | 1 | 1 | 1 | – | – | – |
| Yeasts | 1 | 1 | 1 | – | – | – |
| Candida tropicalis | 1 | 1 | 1 | – | – | – |
| Total | 42 |
aScore values higher than 2.0 for Bruker Biotyper software
bScore values lower than 1.5 for Bruker Biotyper software
cScore values between 2.0 and 1.7 for Bruker Biotyper software
d S. mutans was misidentified as L. plantarum