Skip to main content

Table 1 Comparison of the sensitivities of Vitek 2 and MALDI-TOF MS in the identification of Gram negative bacteria to the species and genus levels

From: Comparison of biomarker based Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) and conventional methods in the identification of clinically relevant bacteria and yeast

Organism (n)

Number (%) of isolates with Correct identification to the species level:

Number (%) of isolates with Correct identification to the genus level:

Vitek 2

MALDI-TOF MS

P value

Vitek 2

MALDI-TOF MS

P value

E coli (55)

48 (87.3)

55 (100.0)

0.006

48 (87.3)

55 (100.0)

0.006

Klebsiella pneumoniae (33)

32 (97.0)

33 (100.0)

0.314

32 (97.0)

33 (100.0)

0.314

Klebsiella oxytoca (4)

3 (75.0)

4 (100.0)

0.285

4 (100.0)

4 (100.0)

 

Pseudomonas aeruginosa (14)

14 (100.0)

14 (100.0)

 

14 (100.0)

14 (100.0)

 

Pseudomonas mendocina (1)

0 (0.0)

1 (100.0)

 

1 (100.0)

1 (100.0)

 

Pseudomonas pseudoalcaligenes (1)

0 (0.0)

1 (100.0)

 

1 (100.0)

1 (100.0)

 

Acinetobacter baumannii (18)

18 (100.0)

18 (100.0)

 

18 (100.0)

18 (100.0)

 

Acinetobacter genomospecies 13BJ/14TU (1)

0 (0.0)

1 (100.0)

 

1 (100.0)

1 (100.0)

 

Acinetobacter ursingii (1)

1 (100.0)

1 (100.0)

 

1 (100.0)

1 (100.0)

 

Citrobacter freundii (6)

5 (83.3)

6 (100.0)

0.296

6 (100.0)

6 (100.0)

 

Citrobacter koseri (3)

3 (100.0)

3 (100.0)

 

3 (100.0)

3 (100.0)

 

Enterobacter cloacae (12)

8 (66.7)

12 (100.0)

0.028

9 (75.0)

12 (100.0)

0.064

Enterobacter aerogenes (5)

5 (100.0)

5 (100.0)

 

5 (100.0)

5 (100.0)

 

Enterobacter gergoviae (1)

1 (100.0)

1 (100.0)

 

1 (100.0)

1 (100.0)

 

Haemophilus influenzae (4)

3 (75.0)

4 (100.0)

0.285

3 (75.0)

4 (100.0)

 

Morganella morganii (8)

7 (87.5)

8 (100.0)

0.302

8 (100.0)

8 (100.0)

 

Proteus mirabilis (7)

7 (100.0)

7 (100.0)

 

7 (100.0)

7 (100.0)

 

Proteus penneri/vulgaris (7)

6 (85.7)

7 (100.0)

0.299

7 (100.0)

7 (100.0)

 

Providencia rettgeri (1)

1 (100.0)

1 (100.0)

 

1 (100.0)

1 (100.0)

 

Stenotrophomonas maltophilia (10)

7 (70.0)

10 (100.0)

0.06

7 (70.0)

10 (100.0)

0.06

Serratia marcescens (1)

1 (100.0)

1 (100.0)

 

1 (100.0)

1 (100.0)

 

Vibrio alginolyticus (1)

1 (100.0)

1 (100.0)

 

1 (100.0)

1 (100.0)

 

Elizabethkingia meningoseptica (1)

1 (100.0)

1 (100.0)

 

1 (100.0)

1 (100.0)

 

Total (195)

172 (88.2)

195 (100.0)

0.000

180 (92.3)

195 (100.0)

0.000