Background
Methods
Study design, setting and patients
Data sources
Blood culture collection, processing and reporting
Definitions
Covariates
Statistical analysis
Results
Cohort study
Admission service
Overall cohort (n = 1801) | Subset with repeat blood cultures (n = 701) | |||||
---|---|---|---|---|---|---|
No repeat cultures (n = 1100) | Repeat cultures (n = 701) |
P
| Cleared bacteremia (n = 583) | Persistent bacteremia (n = 118) |
P
| |
Male n(%) | 576 (52.4) | 442 (63.1) | <0.001
| 361 (61.9) | 80 (67.8) | 0.23 |
Age(y) median (IQR) | 71 (56.5–82) | 66 (51–77) | <0.001
| 65 (51–77) | 68 (52–80) | 0.26 |
Length of stay(d) median (IQR) | 12 (5–30) | 26 (12–48) | <0.001
| 26 (12–50) | 25 (12–41) | 0.59 |
Hospital-acquired n(%) | 514 (46.7) | 389 (55.5) | <0.001
| 333 (57.1) | 55 (46.6) |
0.036
|
Admitting service n(%) | ||||||
Medical | 495 (45.0) | 266 (37.9) |
0.003
| 201 (34.5) | 65 (55.1) | <0.001
|
Surgical | 390 (35.5) | 310 (44.2) | <0.001
| 272 (46.7) | 39 (33.1) |
0.007
|
Heme-Onc | 215 (19.5) | 125 (17.8) | 0.36 | 110 (18.9) | 14 (11.9) | 0.07 |
Organism n(%) | ||||||
Total Gram-positive bacteria | 425 (38.6) | 457 (65.2) | <0.001
| 367 (63.0) | 90 (76.3) |
0.006
|
S. aureus
| 97 (8.8) | 162 (23.1) | <0.001
| 108 (18.5) | 53 (44.9) | <0.001
|
Skin commensals | 62 (5.6) | 114 (16.3) | <0.001
| 98 (16.8) | 16 (13.6) | 0.38 |
Enterococcus spp. | 110 (10.0) | 102 (14.6) |
0.004
| 82 (14.1) | 20 (16.9) | 0.42 |
S. pneumoniae
| 22 (2.0) | 11 (1.6) | 0.506 | 11 (1.9) | 0 | 0.13 |
Viridans group streptococci | 48 (4.4) | 41 (5.9) | 0.156 | 39 (6.7) | 2 (1.7) |
0.031
|
β-hemolytic streptococci | 46 (4.2) | 23 (3.3) | 0.33 | 23 (4.0) | 0 |
0.021
|
S. anginosus group | 31 (2.8) | 11 (1.6) | 0.087 | 10 (1.7) | 1 (0.9) | 0.70 |
Other Gram-positive bacteria | 35 (3.2) | 30 (4.3) | 0.22 | 29 (5.0) | 1 (0.9) |
0.044
|
Total Gram-negative bacteria | 654 (59.4) | 247 (35.2) | <0.001
| 220 (37.7) | 27 (22.9) |
0.002
|
E. coli
| 329 (29.9) | 90 (12.8) | <0.001
| 84 (14.4) | 6 (5.1) |
0.006
|
Klebsiella spp. | 143 (13.0) | 43 (6.1) | <0.001
| 33 (5.7) | 10 (8.5) | 0.25 |
Pseudomonas spp. | 45 (4.1) | 32 (4.6) | 0.63 | 27 (4.6) | 5 (4.2) | 0.85 |
AmpC-producers | 102 (9.3) | 59 (8.4) | 0.54 | 53 (9.1) | 6 (5.1) | 0.15 |
Other Gram-negative bacteria | 69 (6.3) | 39 (5.6) | 0.54 | 35 (6.0) | 4 (3.4) | 0.26 |
Anaerobes | 86 (7.8) | 34 (4.9) |
0.014
| 32 (5.5) | 2 (1.7) | 0.1 |
Polymicrobial n(%) | 107 (9.7) | 75 (10.7) | 0.51 | 66 (11.3) | 9 (7.6) | 0.24 |
Mortality n(%) | ||||||
2-day | 97 (8.8) | - | - | - | - | - |
7-day | 44 (4.0) | 42 (6.0) | 0.053 | 29 (5.0) | 13 (11.0) |
0.012
|
30-day | 123 (11.2) | 189 (27.0) | <0.001
| 160 (27.4) | 29 (24.6) | 0.52 |
Microbiology
Outcomes
Nested case control analysis
Population characteristics
Cleared bacteremia (n = 118) | Persistent bacteremia (n = 118) |
P
| |
---|---|---|---|
Male n (%) | 70 (59.8) | 80 (67.8) | 0.18 |
Age(y) median (IQR) | 66.5 (54–77) | 68 (52–80) | 0.61 |
Comorbidities n (%) | |||
Cardiac | 41 (34.7) | 45 (38.1) | 0.59 |
Respiratory | 10 (8.5) | 6 (5.1) | 0.30 |
Liver | 7 (5.9) | 3 (2.5) | 0.22 |
Diabetes | 24 (20.3) | 34 (28.8) | 0.13 |
Dialysis | 8 (6.8) | 13 (11.0) | 0.25 |
Solid tumor | 33 (28.0) | 24 (20.3) | 0.17 |
Hematologic malignancy | 14 (11.9) | 7 (5.9) | 0.11 |
Burn | 6 (5.1) | 6 (5.1) | 1.0 |
Polytrauma | 13 (11.0) | 11 (9.3) | 0.67 |
HIV | 1 (0.9) | 1 (0.9) | 1.0 |
Neutropenia | 15 (12.7) | 8 (6.8) | 0.12 |
Length of stay(d) median(IQR) | 24 (13–52) | 25 (12–41) | 0.44 |
Admitting service n(%) | |||
Medical | 43 (36.4) | 65 (55.1) |
0.004
|
Surgical | 51 (43.2) | 39 (33.1) | 0.11 |
Heme-Onc | 24 (20.3) | 14 (11.9) | 0.71 |
ICU within 72 h of bacteremia n(%) | 44 (37.3) | 39 (33.1) | 0.54 |
Hospital-acquired n (%) | 58 (49.2) | 55 (46.6) | 0.70 |
Polymicrobial n(%) | 21 (17.8) | 9 (7.6) |
0.019
|
Organism n(%) | |||
Total Gram-positive bacteria | 77 (65.3) | 90 (76.3) |
0.044
|
S. aureus
| 26 (22.0) | 53 (44.9) | <0.001
|
Skin commensals | 10 (8.5) | 16 (13.6) | 0.29 |
Enterococcus spp. | 23 (19.5) | 20 (16.9) | 0.50 |
S. pneumoniae
| 5 (4.2) | 0 |
0.03
|
Viridans group streptococci | 11 (9.3) | 2 (1.7) |
0.011
|
β-hemolytic streptococci | 5 (4.2) | 0 |
0.03
|
S. anginosus group | 3 (2.5) | 1 (0.9) | 0.31 |
Other Gram-positive bacteria | 6 (5.1) | 1 (0.9) | 0.062 |
Total Gram-negative bacteria | 44 (37.3) | 27 (22.9) |
0.016
|
E. coli
| 16 (13.6) | 6 (5.1) |
0.048
|
Klebsiella spp. | 8 (6.8) | 10 (8.5) | 0.62 |
Pseudomonas spp. | 6 (5.1) | 5 (4.2) | 0.76 |
AmpC-producing bacteria | 12 (10.2) | 6 (5.1) | 0.14 |
Other Gram-negative bacteria | 6 (5.1) | 4 (3.4) | 0.54 |
Anaerobic bacteria | 5 (4.2) | 2 (1.7) | 0.28 |
7-day mortality n(%) | 5 (4.2) | 13 (11.0) |
0.05
|
30-day mortality n(%) | 13 (11.0) | 29 (24.6) |
0.006
|
Clinical syndrome
Cleared bacteremia (n = 118) | Persistent bacteremia (n = 118) |
P
| |
---|---|---|---|
Clinical Syndrome n(%) | |||
Endovascular | 28 (23.7) | 52 (44.1) | <0.001
|
Endocarditis | 9 (7.6) | 18 (15.3) | 0.066 |
Central line/device/graft | 19 (16.1) | 34 (28.8) |
0.019
|
Extravascular | 68 (57.6) | 54 (45.8) | 0.068 |
Abdominal | 19 (16.1) | 10 (8.5) | 0.074 |
Cardio-respiratory | 18 (15.3) | 11 (9.3) | 0.17 |
Genito-urinary | 20 (16.9) | 7 (5.9) |
0.008
|
SSTI | 9 (7.6) | 15 (12.7) | 0.20 |
Epidural abscess/discitis | 1 (0.9) | 7 (5.9) |
0.036
|
Septic arthritis | 1 (0.9) | 5 (4.2) | 0.121 |
Unknown | 22 (18.6) | 12 (10.2) | 0.064 |
Clinical parameters at time of repeat culture [present/total (%)] | |||
SIRS | 51/105 (48.6) | 40/98 (40.8) | 0.27 |
Leukocytosis | 50/118 (42.4) | 48/114 (42.1) | 0.97 |
Fever | 34/106 (32.1) | 25/99 (25.3) | 0.28 |
Physician concern of instability | 36/105 (34.3) | 25/96 (26.0) | 0.20 |
Clinical status when repeat cultures were drawn
Antibiotics and source control
Cleared bacteremia (n = 118) | Persistent bacteremia (n = 118) |
P
| |
---|---|---|---|
Appropriate antibiotics n (%) | |||
Empiric | 67 (57.8) | 72 (61.0) | 0.51 |
Guided by index culture | 51 (43.2) | 40 (33.9) | 0.14 |
Guided by repeat culture | 0 | 3 (2.5) | 0.123 |
Source control required n (%) | 61 (51.7) | 74 (62.7) | 0.087 |
Endovascular
| 32 (27.1) | 41 (34.7) | 0.21 |
Line removal | 28 (23.7) | 35 (29.7) | - |
PPM/ICD explantation | 1 (0.9) | 1 (0.9) | - |
Valve surgery | 3 (2.5) | 6 (5.1) | - |
Aortic graft replacement | 0 | 1 (0.9) | - |
Spine and Joint
| 3 (2.5) | 10 (8.5) | 0.051 |
Epidural abscess/spinal | 2 (1.7) | 5 (4.2) | - |
Peripheral joint | 1 (0.9) | 5 (4.2) | - |
Thoraco-abdominal
| 18 (15.3) | 13 (11.0) | 0.34 |
Pericardiocentesis | 0 | 1 (0.9) | - |
Empyema | 2 (1.7) | 2 (1.7) | - |
Intra-abdominal abscess | 3 (2.5) | 1 (0.9) | - |
Liver abscess | 2 (1.7) | 1 (0.9) | - |
Cholangitis | 4 (3.4) | 2 (1.7) | - |
Peritonitis | 1 (0.9) | 2 (1.7) | - |
Nephrostomy tube | 1 (0.9) | 2 (1.7) | - |
Foley removal | 4 (3.4) | 2 (1.7) | - |
ICP monitor removal | 1 (0.9) | 0 | - |
SSTI
| 8 (6.8) | 10 (8.5) | 0.62 |
Debridement/abscess drainage | 8 (6.8) | 8 (6.8) | - |
Amputation | 0 | 2 (1.7) | - |
Source control done in 48 h n (%) | 32/61 (52.5) | 22/74 (29.7) | <0.001
|
Endovascular | 16/32 (50.0) | 16/41 (39.0) | 0.35 |
Spine and joint | 2/3 (66.7) | 0/10 |
0.038
|
Thoraco-abdominal | 11/18 (61.1) | 6/13 (46.2) |
0.046
|
SSTI | 3/8 (37.5) | 0/10 | 0.069 |
Multivariate analysis
Variable | Odds ratio | 95 % CI |
P value |
---|---|---|---|
Sex | |||
Male | 2.59 | 1.28–5.25 |
0.008
|
Femalea
| 1.00 | 1.00 | 1.00 |
Admitting service | |||
Medical in-patient | 2.80 | 1.34–5.84 |
0.006
|
Heme-onc in-patient | 1.21 | 0.44–3.33 | 0.71 |
Surgical in-patienta
| 1.00 | 1.00 | 1.00 |
Organism | |||
S. aureus
| 4.49 | 1.88–10.73 | <0.001
|
Other Gram-positive bacteria | 0.80 | 0.35–1.82 | 0.59 |
Anaerobes | 0.96 | 0.15–6.38 | 0.97 |
All Gram-negative bacteriaa
| 1.00 | 1.00 | 1.00 |
Source of bacteremia | |||
Endovascular | 7.66 | 2.30–25.48 | <0.001
|
Epidural abscess/discitis | 26.99 | 1.91–391.08 |
0.015
|
Other extravascular source | 3.02 | 0.97–9.41 | 0.057 |
Unknown sourcea
| 1.00 | 1.00 | 1.00 |