TABLE 3.
Culture-Proven Organisms Stratified by Appropriateness in Empiric Antimicrobial Therapy and Unadjusted Log-Binomial Regression Analysis of Inappropriateness*
| Organism | Inappropriate, n (%) | Appropriate, n (%) | p ** | RR (95%CI)**† |
|---|---|---|---|---|
| No. patients | 597 (21) | 2,258 (79) | — | — |
| No. infectious episodes |
2,085 (29) | 5,073 (71) | — | — |
| Fungal | 600 (29) | 649 (13) | <0.0001 | 1.9 (1.7–2.1) |
| C. albicans | 301 (14) | 298 (6) | <0.0001 | 1.9 (1.7–2.0) |
| C. glabrata | 125 (6) | 125 (2) | <0.0001 | 1.7 (1.5–2.0) |
| Gram-negative bacteria | 831 (40) | 1,968 (39) | 0.36 | 1.0 (0.96–1.1) |
| Escherichia coli | 133 (6) | 462 (9) | 0.0011 | 0.76 (0.65–0.90) |
| Klebsiella pneumoniae | 82 (4) | 257 (5) | 0.11 | 0.84 (0.69–1.04) |
| Serratia species | 50 (2) | 133 (3) | 0.41 | 0.91 (0.71–1.1) |
| Pseudomonas aeruginosa | 184 (9) | 377 (7) | 0.14 | 1.1 (0.97–1.3) |
| E. cloacae | 122 (6) | 164 (3) | <0.0001 | 1.5 (1.3–1.7) |
| GP bacteria | 1,129 (54) | 1,833 (36) | <0.0001 | 1.7 (1.6–1.9) |
| MSSA | 63 (3) | 345 (7) | <0.0001 | 0.54 (0.43–0.69) |
| MRSA | 187 (9) | 249 (5) | <0.0001 | 1.6 (1.4–1.8) |
| Coagulase-negative Staphylococcus | 77 (4) | 98 (2) | <0.0001 | 1.6 (1.3–1.9) |
| E. faecalis | 171 (8) | 291 (6) | 0.0001 | 1.3 (1.1–1.5) |
| E. faecium | 66 (3) | 54 (1) | <0.0001 | 1.9 (1.6–2.3) |
| VRE | 148 (7) | 85 (2) | <0.0001 | 2.2 (2.0–2.5) |
| Streptococcus species | 115 (6) | 259 (5) | 0.35 | 1.1 (0.92–1.3) |
| Anaerobic bacteria | 142 (7) | 505 (10) | <0.0001 | 0.72 (0.61–0.84) |
| Clostridium difficile | 15 (1) | 234 (5) | <0.0001 | 0.17 (0.10–0.30) |
| Other | 174 (8) | 963 (19) | <0.0001 | 0.48 (0.42–0.56) |
*
Characteristics analyzed per infectious episode.
**
To accommodate for a correlated data structure corresponding to multiple episodes of infection per individual, the analysis of inappropriateness among infectious episodes was computed using a GEE approach with robust SEs (i.e., Huber-White sandwich variance estimates).
†
The 1.0 referent for each type of organism is the absence of the organism.
CI, confidence interval; MRSA, methicillin resistant S. aureus; MSSA, methicillin-sensitive S. aureus; RR, relative risk; VRE, vancomycin-resistant enterococcus.