Factor
|
1999–2003 Cohort
|
2015–2017 Cohort
|
p value
|
---|
Polymicrobial
|
35/71 (49%)
|
44/136 (32%)
|
0.01
|
Nosocomial PLA
|
6/71 (9%)
|
6/136 (4.4%)
|
0.19
|
Streptococcus anginosus group
|
31/71
|
54/136
|
0.34
|
Klebsiella species
|
19/71
|
34/136
|
0.45
|
Anaerobesa
|
14/71
|
22/136
|
0.32
|
Escherichia coli
|
11/71
|
24/136
|
0.43
|
Enterococcus species
|
5/71
|
12/136
|
0.44
|
Staphylococcus aureus
|
4/71
|
2/136
|
0.11
|
Other bacteria
|
11/71
|
26/136
|
0.33
|
Culture negativeb
|
12/71
|
13/136
|
0.10
|
Antimicrobial resistant isolate present
|
1/71
|
11/136
|
0.04
|
- aAnaerobes included Clostridium perfringens, Bacteroides species, Peptostreptococcus species, Fusobacterium species, Actinomyces species, Prevotella species, Lactobacillus species, Veillonella species. The prevalence of these organisms was not different between the two cohorts
- bPatients classified as culture negative had negative blood and aspiration cultures (4/136) or negative blood cultures only when aspiration was not performed (9/136)