Table 2.
Results of the Blindfolded Study
| Species | Strains Identified by MALDI-TOF MS (n) | Strains Routinely Identified by VITEK II (n) | Strains Correctly Identified by MALDI-TOF MS After Re-testing (n) | Strains Correctly Identified by MALDI-TOF MS (%) |
|---|---|---|---|---|
| Escherichia coli | 6/6 | 100 | ||
| Klebsiella pneumoniae | 5/6 | 5/51 | 100 | |
| Klebsiella oxytoca | 6/6 | 100 | ||
| Enterobacter cloacae | 5/6 | 5/51 | 100 | |
| Enterobacter aerogenes | 5/6 | 5/51 | 100 | |
| Proteus mirabilis | 6/6 | 100 | ||
| Proteus vulgaris | 7/7 | 100 | ||
| Salmonella Enteritidis | 5/5 | 100 | ||
| Salmonella Typhimurium | 6/6 | 100 | ||
| Serratia marcescens | 7/7 | 8/82 | 100 | |
| Shigella sonnei | 4/5 | 4/5 | 80 | |
| Yersinia enterocolitica | 6/6 | 100 | ||
| Citrobacter freundii | 7/7 | 100 | ||
| Morganella morganii | 7/7 | 100 | ||
| Acinetobacter baumanii | 7/7 | 100 | ||
| Pseudomonas aeruginosa | 6/6 | 100 | ||
| Total | 95/99 | 27/28 | 99 | |
1
One strain was excluded due to ambiguous identification
2
One strain was previously misidentified by VITEK II as E. aerogenes. The strain was identified by re-testing as S. marcescens, implicating now a total amount of eight S. marcescens in the study.