List of microorganisms identified by routine methods/number of isolates | Number of isolates identified by MALDI-TOF MS at the species level | Number of isolates identified by MALDI-TOF MS at the genus level only | Isolates not identified by MALDI-TOF MS | Isolates with discordant results | Sensitivity (%) | Specificity (%) | PPV (%) | NPV (%) |
---|---|---|---|---|---|---|---|---|
Staphylococcus aureus (36) | 36 | – | – | 100 | 100 | 100 | 100 | |
Staphylococcus epidermidis (46) | 45 | 1 | – | 82.1 | 97.9 | 93.3 | 94.2 | |
Staphylococcus hominis (9) | 8 | – | 1 | |||||
Staphylococcus haemolyticus (2) | 2 | – | – | |||||
Staphylococcus capitis (3) | 2 | – | 1 | |||||
Staphylococcus cohnii (1) | – | – | 1 | |||||
Staphylococcus simulans (2) | 2 | – | – | |||||
Kocuria kristinae (1) | 1 | – | – | |||||
Dolosigranulum pigrum (1) | – | – | 1 | |||||
Rothia mucilaginosa (2) | 2 | – | – | |||||
Micrococcus luteus (16) | 7 | – | 9 | L. monocytogenes (2) L. adecarboxylata (2) P. baroniae (1) | ||||
Micrococcus terreus (1) | – | – | 1 | |||||
Total GPC resembling Staphylococcus (120) | 105 | 1 | 14 | 88.3 | 97.5 | 95.5 | 93.2 | |
Streptococcus agalactiae (7) | 6 | – | 1 | |||||
Streptococcus pneumoniae (6) | 5 | – | 1 | |||||
Streptococcus mitis/oralis group (9) | 5 | – | 4 | |||||
Streptococcus parasanguinis (2) | 2 | – | – | |||||
Streptococcus sanguinis (1) | 1 | – | – | |||||
Streptococcus intermedius (1) | 1 | – | – | |||||
Other Viridans group of Streptococci (6) | – | 2 | 4 | |||||
Streptococcus constellatus (1) | – | – | 1 | |||||
Granulicatella adiacens (1) | 1 | – | – | |||||
Abiotrophia defective (2) | 1 | – | – | L. adecarboxylata (1) | ||||
Enterococcus faecalis (23) | 23 | – | – | 100 | 100 | 100 | 100 | |
Enterococcus faecium (2) | 2 | – | – | |||||
Total GPC resembling Streptococcus (61) | 47 | 2 | 12 | 80.3 | 99.6 | 98 | 95.5 | |
Clostridium perfringen (2) | 2 | – | – | |||||
Clostridium septicum (1) | 1 | – | – | |||||
Bacillus cereus (5) | 4 | – | 1 | |||||
Bacillus megaterium (1) | 1 | – | – | |||||
Bacillus altitudinis/pumilus (1) | 1 | – | – | |||||
Brevibacterium luteolum (1) | 1 | – | – | |||||
Bacillus simplex (1) | 1 | – | – | |||||
Bacillus gibsonii (1) | 1 | – | – | |||||
Dermabacter hominis (1) | – | – | 1 | |||||
Actinomyces viscosus (1) | – | – | 1 | |||||
Curtobacterium flaccumfaciens (1) | – | – | 1 | |||||
Dietzia cinnamea (1) | – | – | 1 | S. cornosus (1) | ||||
Corynebacterium aurimucosum (1) | – | 1 | – | |||||
Corynebacterium spp. (2) | – | – | 2 | |||||
Total Gram positive rods (20) | 12 | 1 | 7 | 65 | 99.7 | 92.9 | 97.7 | |
Escherichia coli (29) | 29 | – | – | |||||
Klebsiella pneumoniae (11) | 11 | – | – | |||||
Klebsiella oxytoca (2) | 2 | – | – | |||||
Enterobacter cloacae complex (22) | 21 | – | 1 | |||||
Salmonella enterica subsp. enterica (14) | 14 | – | – | |||||
Serratia marcescens (4) | 4 | – | – | |||||
Morganella morganii (1) | 1 | – | – | |||||
Pseudomonas aeruginosa (9) | 9 | – | – | |||||
Acinetobacter radioresistans (1) | 1 | – | – | |||||
Acinetobacter lwoffii (1) | 1 | – | – | |||||
Acinetobacter ursingii (1) | 1 | – | – | |||||
Acinetobacter baumannii (1) | 1 | – | – | |||||
Acinetobacter johnsonii (1) | 1 | – | – | |||||
Stenotrophomonas maltophilia (7) | 7 | – | – | |||||
Neisseria meningitides (1) | 1 | – | – | |||||
Moraxella catarrhalis (2) | 2 | – | – | |||||
Total Gram negatives (107) | 106 | – | 1 | 99 | 100 | 100 | 99.5 | |
Candida albicans (1) | – | – | 1 | |||||
Candida parapsilosis (9) | – | – | 9 | |||||
Total yeast (10) | – | – | 10 |