Table 2.
Comparison of species identification by official (Score value) and visual interpretations of MALDI-TOF seven profile peaks, with species annotation based on the m/z values described by Werno et al.7.
| Confirmed ID | m/z value | Test results based on score value | Test results based on visual evaluation value | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Profile | 2625 | 2911 | 2937.5 | 5253 | 5824 | 5877 | 6955 | Score tested/correct | Visual tested/correct |
| S. pneumoniae (typeable) | − | − | + | − | − | + | − | 22/22 | 22/22 |
| S. pneumoniae (nontypeable) | − | − | + | − | − | + | − | 25/241 | 25/25 |
| S. pseudopneumoniae | + | − | + | + | − | +/− | − | 9/42 | 9/9 |
| S. mitis | + /− | +/− | +/− | +/− | +/− | +/− | +/− | 20/103 | 20/144 |
| S. oralis | − | + | − | − | + | − | +/− | 2/2 | 2/15 |
| S. australis | − | − | − | − | − | − | − | 2/06 | 2/07 |
| S. sanguinis | − | − | − | +/− | − | − | +/− | 4/4 | 4/08 |
+: only strains with peaks were found.+/−: strains both with and without peaks were detected. −: no strains with peaks were detected.
1One specimen identified as S. pseudopneumoniae.
2Four isolates identified as S. pneumoniae, one ID as S. oralis.
3Six isolates identified as S. oralis, three isolate ID as S. pneumoniae, one isolate ID as S. pseudopneumoniae.
4Three isolates identified as S. pneumoniae, three S. mitis/S. oralis.
5One isolate identified as S. mitis/S. oralis.
6Both isolates identified as S. parasanguinis.
7Both isolates could not be identified.
8All isolates could not be identified.