Table 2.

Multivariable analysis of factors associated with CRE bacteremia in neutropenic patients compared to controls.

Variable	Adjusted OR using primary control group (95% CI)1, 2	P	Adjusted OR using secondary control group (95% CI)3	P
β-lactam/β-lactamase inhibitor within previous 30 days	3.2 (1.1–9.3)	0.03	5.0 (1.2–22)	0.03
Carbapenem within previous 30 days	3.0 (1.0–9.2)	0.05	7.0 (1.9–26)	0.004
Receiving TMP-SMX at BSI onset	24 (3.8–151)	0.001	33 (4.2–256)	0.001
Receiving glucocorticoids at BSI onset	5.4 (1.7–17)	0.004	4.9 (1.4–17)	0.01
Prior CRE at any site within the previous 90 days	12 (1.2–113)	0.03	Unable to include4	N/A
ICU stay within previous 30 days	2.7 (0.9–7.9)	0.07	11 (2.8–42)	0.001
Receiving cephalosporin at BSI onset	Not significant	N/A	7.7 (1.1–54)	0.04
Receiving fluoroquinolone at BSI onset	Not significant	N/A	6.4 (1.5–27)	0.01
Renal disease5	Not significant	N/A	21.0 (3.9–111)	<0.001

Abbreviations: BSI, bloodstream infection; CI, confidence interval; CRE, carbapenem-resistant Enterobacteriaceae; ICU, intensive care unit; OR, odds ratio; TMP-SMX, trimethoprim-sulfamethoxazole.

¹The primary control group consisted of BSIs due to pathogens other than carbapenem-resistant Gram-negative bacteria.

²The C statistic for this multivariable model was 0.83.

³The secondary control group consisted of BSIs due to carbapenem-susceptible Gram-negative bacteria.

⁴This variable could not be entered into the multivariate model because no episodes in the control group had a prior CRE at any site.

⁵Renal disease was defined as having a serum creatinine > 3 mg/dL, receiving dialysis, or history of a kidney transplant [7].