Table 3. Comparison of the results between the conventional method and MALDI-TOF in 31 specimens with colony counts of 104-105 CFU/mL.
| Conventional identification (N of isolates) | Coincidence (%) | MALDI-TOF MS identification (N of isolates) | |
|---|---|---|---|
| Species level | Genus level | ||
| Escherichia coli (5) | 40.0 | 40.0 | Escherichia coli (2) |
| No reliable identification (2) | |||
| Insufficient peak (1) | |||
| Klebsiella pneumoniae (2) | 100 | 100 | Klebsiella pneumoniae (2) |
| Klebsiella oxytoca (1) | 100 | 100 | Klebsiella oxytoca (1) |
| Enterobacter aerogenes (1) | 100 | 100 | Enterobacter aerogenes (1) |
| Morganella morganii (1) | 100 | 100 | Morganella morganii (1) |
| Proteus mirabilis (1) | 0 | 0 | No reliable identification (1) |
| Total gram-negative bacteria (11) | 54.5 | 54.5 | |
| Enterococcus faecalis (1) | 0 | 0 | No reliable identification (1) |
| Enterococcus faecium (2) | 50.0 | 50.0 | Enterococcus faecium (1) |
| No reliable identification (1) | |||
| Staphylococcus aureus (1) | 0 | 0 | No reliable identification (1) |
| Streptococcus agalactiae (1) | 0 | 0 | Insufficient peak (1) |
| Streptococcus anginosus (1) | 0 | 0 | No reliable identification (1) |
| Coagulase-negative staphylococci (1) | 0 | 0 | No reliable identification (1) |
| Total gram-positive cocci (7) | 14.3 | 14.3 | |
| Bacillus spp.(1) | 0 | 0 | No reliable identification (1) |
| Candida albicans (5) | 0 | 0 | No reliable identification (4) |
| Insufficient peak (1) | |||
| Candida glabrata (4) | 25.0 | 25.0 | Candida glabrata (1) |
| No reliable identification (3) | |||
| Candida tropicalis (3) | 0 | 0 | No reliable identification (2) |
| Insufficient peak (1) | |||
| Total yeast (12) | 8.3 | 8.3 | |
| Total (31) | 29.0 | 29.0 | |
Abbreviations: MALDI-TOF MS, matrix-assisted laser desorption ionization time-of-flight mass spectrometry; CFU, colony-forming unit.