Table 3 Causative pathogens of bacterial brain abcess.

	Initial IVRBA	Subsequent IVRBA	Non‐IVRBA
	n = 45	n = 17	n = 117
Gram‐negative bacilli (n = 39)
Klebsiella pneumoniae	5	1	12
Pseudomonas aeruginosa	3	0	1
Acinetobacter baumannii	2	0	1
Escherichia coli	1	1	1
Enterobacter cloacae	0	1	2
Other*	0	2	6
Streptococcus species (n = 27)
Streptococcus viridans	7	3	15
Other†	1	0	1
Staphylococcus species (n = 10)
Staphylococcus aureus	0	0	7
Coagulase‐negative Staphylococcus	1	1	1
Anaerobes (n = 24)
Fusobacterium species	2	1	5
Bacteriodes species	4	0	2
Peptostreptococcus species	2	0	2
Other‡	0	1	5
Mixed infection (n = 23)	8	2	13
Negative culture (n = 56)	9	4	43

IVRBA, intraventricular rupture of brain abscesses.

*Other Gram‐negative bacilli included Salmonella species (2), Serratia marcescens (2), Klebsiella oxytoca (1), Vibrio cholerae non‐O1 (1), Proteus mirabilis (1) and Pasteurella species (1).

†Other streptococci included non‐A, non‐B and non‐D streptococci (1) and Group B Streptococcus (1).

‡Other anaerobes included Corynebacterium species (3), Peptococcus species (2) and Propriobacterium acne (1).