TABLE 1.

Microbiological identification by MALDI-TOF-MS in blood cultures spiked with different species

Identification obtained from subculture (biochemical or molecular techniques)	No. of samples:
	Tested	With identification by MALDI-TOF-MS to:				With unacceptable MALDI-TOF-MS profile(s)
		Species	Groupa	Genus	Family
Staphylococcus species
S. aureus	42	42
S. epidermidis	7	7
S. haemolyticus	7	6	1 (CNS group)
S. hominis	3	3
S. warneri	5	5
S. lugdunensis	2	2
Micrococcus luteus	5	3	1 (CNS group)		1
Streptococcus species
S. mitis	6		6 (S. pneumoniae/S. mitis group)
S. pneumoniae	6		6 (S. pneumoniae/S. mitis group)
S. gordonii	4		4 (oral Streptococcus group)
Enterococcus faecalis	14	14
Gram-negative nonfermenting bacilli
Pseudomonas aeruginosa	39	38			1
Stenotrophomonas maltophilia	20	18				2
Acinetobacter baumannii	15	15
Enterobacteriaceae
Escherichia coli	20	19				1
Enterobacter cloacae	18	13			5
Citrobacter freundii	16	14			1	1
Klebsiella oxytoca	17	17
Klebsiella pneumoniae	20	18	1 (KES group)			1
Proteus mirabilis	18	17		1
Haemophilus influenzae	2	2
Anaerobic bacteria
Clostridium perfringens	2	2
Fusobacterium necrophorum	3	3
Bacteroides fragilis	1	1
Candida albicans	10	10
Other Candida species	10	10
Total	312	279	19	1	8	5

^aCNS group, coagulase-negative Staphylococcus; S. pneumoniae/S. mitis group, no differentiation between S. pneumoniae and S. mitis; oral Streptococcus group, includes all oral species of streptococci except the S. milleri group; KES group, no identification between the species K. pneumoniae and Enterobacter aerogenes (KES, Klebsiella-Enterobacter-Serratia).