Table 1.
Comparison of the results of the Bruker Biotyper and ASTA MicroIDSys systems.
| Species | Bruker ≥ 2.0 | Bruker 1.7≤, <2.0 | Total | ||
|---|---|---|---|---|---|
| ASTA ≥ 140 | ASTA < 140 | ASTA ≥ 140 | ASTA < 140 | ||
| Gram-negative bacilli | |||||
| Escherichia coli | 134 | 1 | 1 * 1 | 136 | |
| Klebsiella pneumoniae | 79 | 79 | |||
| Acinetobacter baumannii | 48 | 48 | |||
| Pseudomonas aeruginosa | 45 | 1 | 46 | ||
| Proteus mirabilis | 18 | 18 | |||
| Enterobacter aerogenes | 15 | 15 | |||
| Enterobacter cloacae | 9 | 9 | |||
| Serratia marcescens | 8 | 8 | |||
| Stenotrophomonas maltophilia | 7 | 7 | |||
| Haemophilus influenzae | 5 | 5 | |||
| Citrobacter freundii | 4 | 4 | |||
| Acinetobacter baylyi | 3 * 2 | 3 | |||
| Providencia rettgeri | 2 | 2 | |||
| Alcaligenes faecalis | 2 | 2 | |||
| Morganella morganii | 2 | 2 | |||
| Citrobacter amalonaticus | 2 | 2 | |||
| Achromobacter xylosoxidans | 2 | 2 | |||
| Acinetobacter nosocomialis | 2 | 2 | |||
| Acinetobacter pittii | 1 | 1 * 3 | 2 | ||
| Providencia stuartii | 1 | 1 | |||
| Salmonella spp. | 1 | 1 | |||
| Aeromonas veronii | 1 | 1 | |||
| Pseudomonas stutzeri | 1 | 1 | |||
| Neisseria gonorrhoeae | 1 | 1 | |||
| Aeromonas caviae | 1 | 1 | |||
| Campylobacter jejuni | 1 | 1 | |||
| Haemophilus parainfluenzae | 1 | 1 | |||
| Brevundimonas vesicularis | 1 * 4 | 1 | |||
| No. of subtotal (%) | 393 (98.0%) | 1 (0.2%) | 6 (1.5%) | 1 (0.2%) | 401 (100%) |
| Gram-positive cocci | |||||
| Staphylococcus aureus | 99 | 99 | |||
| Enterococcus faecium | 63 | 63 | |||
| Enterococcus faecalis | 33 | 33 | |||
| Staphylococcus epidermidis | 25 | 25 | |||
| Staphylococcus haemolyticus | 14 | 4 | 18 | ||
| Streptococcus anginosus | 10 | 4 | 14 | ||
| Streptococcus agalactiae | 10 | 10 | |||
| Staphylococcus hominis | 8 | 1 | 9 | ||
| Staphylococcus lugdunensis | 7 | 7 | |||
| Staphylococcus capitis | 7 | 7 | |||
| Staphylococcus caprae | 5 | 2 | 7 | ||
| Enterococcus casseliflavus | 4 | 4 | |||
| Staphylococcus pettenkoferi | 3 | 3 | |||
| Streptococcus pyogenes | 2 | 2 | |||
| Enterococcus avium | 2 | 2 | |||
| Streptococcus constellatus | 2 | 2 | |||
| Enterococcus raffinosus | 2 | 2 | |||
| Streptococcus mitis | 2 | 2 | |||
| Streptococcus salivarius | 1 | 1 | 2 | ||
| Streptococcus pneumoniae | 1 | 1 | 2 | ||
| Staphylococcus simulans | 1 | 1 | |||
| Micrococcus luteus | 1 | 1 | |||
| Streptococcus dysgalactiae | 1 | 1 | |||
| Enterococcus gallinarum | 1 | 1 | |||
| Streptococcus intermedius | 1 | 1 | |||
| Streptococcus parasanguinis | 1 | 1 | |||
| No. of subtotal (%) | 306 (95.9%) | 1 (0.3%) | 12 (3.8%) | 0 (0.0%) | 319 (100%) |
| Other bacteria | |||||
| Corynebacterium striatum | 25 | 25 | |||
| Clostridium difficile | 9 | 1 | 10 | ||
| Corynebacterium jeikeium | 1 | 1 | 2 | ||
| Clostridium hathewayi | 1 | 1 | |||
| Bacillus cereus | 1 | 1 | |||
| Actinomyces odontolyticus | 1 | 1 | |||
| Bacillus circulans | 1 | 1 | |||
| Corynebacterium tuberculostearicum | 1 | 1 | |||
| No. of subtotal (%) | 39 (92.9%) | 0 (0.0%) | 2 (4.8%) | 1 (2.4%) | 42 (100%) |
| Candida spp. and other fungi † | |||||
| Candida tropicalis | 41 | 1 | 42 | ||
| Candida albicans | 35 | 1 | 36 | ||
| Candida glabrata | 18 | 1 | 19 | ||
| Candida parapsilosis | 6 | 1 | 7 | ||
| Trichosporon asahii | 2 | 2 | |||
| Cryptococcus neoformans | 1 | 1 | |||
| No. of subtotal (%) | 102 (95.3%) | 0 (0.0%) | 4 (3.7%) | 1 (0.9%) | 107 (100%) |
| No. of total (%) | 840 (96.7%) | 2 (0.2%) | 24 (2.8%) | 3 (0.3%) | 869 (100%) |
* When any result was below the cutoff score (<140 for MicroIDSys and <2.0 for Bruker Biotyper), we performed 16S rRNA gene sequencing for bacterial identification. The results of the 16S rRNA gene sequencing are provided in parentheses for the cases whose results by molecular testing were different from those by MALDI–TOF MS (1 E. fergusonii; 2 A. soli; 3 A. calcoaceticus; 4 B. nasdae). † Molecular testing was not performed for fungal isolates.