Table 1.
Comparison of baseline characteristics of included patients and their gram-negative bloodstream infections between cohorts
| Characteristic | Pre-intervention n = 147 |
Post-intervention n = 169 |
P | |
|---|---|---|---|---|
| Age (years), median (IQR) | 62 (49–70) | 58 (46–69) | 0.35 | |
| Gender at birth, n (%) | Female | 74 (50.3) | 84 (49.7) | 0.91 |
| Race, n (%) | White | 104 (70.7) | 102 (60.4) | 0.05 |
| Black | 11 (7.5) | 14 (8.3) | 0.79 | |
| Asian | 8 (5.4) | 5 (2.9) | 0.27 | |
| Other | 24 (16.4) | 48 (28.4) | <0.05 | |
| Ethnicity, n (%) | Hispanic | 83 (56.5) | 100 (59.2) | 0.63 |
| Charlson Comorbidity Index, median (IQR) | 4 (2–5) | 3 (1–5) | 0.30 | |
| Comorbid conditions, n (%) | Injection drug use | 8 (5.4) | 8 (4.7) | 0.77 |
| Solid organ transplant | 4 (2.7) | 2 (1.2) | 0.32 | |
| Bone marrow transplant | 0 (0) | 0 (0) | N/A | |
| Absolute neutrophil count <500 cells/microliter | 1 (0.7) | 1 (0.6) | 0.92 | |
| Causative pathogens, n (%) | Escherichia coli | 92 (62.6) | 100 (59.1) | 0.54 |
| Klebsiella pneumoniae | 20 (13.6) | 27 (16) | 0.55 | |
| Enterobacter cloacae | 8 (5.4) | 10 (5.9) | .86 | |
| Klebsiella oxytoca | 9 (6.1) | 1 (0.6) | < 0.05 | |
| Pseudomonas aeruginosa | 7 (4.8) | 5 (3) | 0.40 | |
| Proteus mirabilis | 5 (3.4) | 6 (3.6) | 0.94 | |
| Other a | 6 (4.1) | 20 (11.8) | < 0.05 | |
| Extended-spectrum beta-lactamase producing organism, n (%) | 18 (12.2) | 26 (15.4) | 0.42 | |
| Antimicrobial rate of resistance, n (%) | Cefazolin b | 65 (44.2) | 64 (37.9) | 0.25 |
| TMP-SMX | 48 (32.7) | 45 (26.6) | 0.24 | |
| Levofloxacin | 23 (15.6) | 21 (12.4) | 0.41 | |
| Suspected source of infection, n (%) | Urinary tract | 83 (56.5) | 111 (65.7) | 0.09 |
| Intra-abdominal | 27 (18.4) | 31 (18.3) | 0.99 | |
| Respiratory | 10 (6.8) | 10 (5.9) | 0.75 | |
| Vascular catheter | 5 (3.4) | 5 (2.9) | 0.82 | |
| Skin and soft tissue | 3 (2) | 6 (3.6) | 0.42 | |
| Other | 19 (12.9) | 6 (3.6) | < 0.05 | |
| Pitt Bacteremia Score, median (IQR) | 1 (0–3) | 1 (0–3) | 0.51 | |
| Intensive care unit admission on day of positive blood culture, n (%) | 63 (42.9) | 54 (32) | < 0.05 | |
| Infectious Diseases consult, n (%) | 48 (32.7) | 51 (30.2) | 0.64 | |
IQR, interquartile ratio; n, number of members; %, percentage of sample size.
a
Acinetobacter baumannii, Citrobacter freundii, Citrobacter koseri, Enterobacter aerogenes, Morganella morganii, Salmonella enterica, Serratia marcescens, and other unidentified species of Enterobacter and Acinetobacter.
b
Susceptibilities for cephalexin and cefdinir are extrapolated from cefazolin per the 2024 Clinical and Laboratory Standards Institute M100 guidance.