TABLE 4.

Comparative yield of clinically important isolates in FN versus SN anaerobic blood culture bottles from patients not on antimicrobial therapy

Microorganism	No. of isolates detected by:			P value
	Both bottles	FN only	SN only
Gram-positive bacteria
Staphylococcus aureus	35	26	6	<0.001
Coagulase-negative staphylococci	19	8	6	NSa
Streptococcus spp.b	6	0	3	NS
Enterococcus spp.c	13	3	2	NS
Bacillus cereus	1	0	0	NS
Gram-negative bacilli
Enterobacteriaceaed	28	9	4	NS
Other gram-negative bacillie	1	0	5	NS
Anaerobic bacteriaf	3	1	1	NS
Yeastsg	0	1	12	<0.01
All microorganisms	106	48	39	NS

^aNS, not significant (P > 0.05).

^bIncludes six isolates of viridans streptococci, two of Streptococcus pneumoniae, and one of group B streptococcus.

^cIncludes 12 of Enterococcus faecium and 6 of Enterococcus faecalis.

^dIncludes 12 of Escherichia coli; 10 of Klebsiella pneumoniae; 7 of E. cloacae; 3 of Klebsiella oxytoca; 3 of Proteus mirabilis; 2 of Enterobacter aerogenes; and 1 each of Citrobacter freundii, Providencia rettgeri, Serratia liquefaciens, and S. marcescens.

^eIncludes five of P. aeruginosa and one of P. oryzihabitans.

^fIncludes three of the Bacteroides thetaiotaomicron/ovatus group, one of Bacteroides fragilis, and one of Bacteroides caccae.

^gIncludes four of Candida albicans; three of C. parapsilosis; two of Candida tropicalis; and one each of Candida glabrata, Candida lusitaniae, Candida spp., and Malassezia furfur.