Table 5. Factors associated with GNB infection in multivariate analysis.

Factor	Univariate analysis			Multivariate analysis
	OR	95% CI	P	aOR	95% CI	P
Female	3.31	1.86–5.88	<0.01	3.02	1.50–6.10	<0.01
Epidural block within 6 months	0.35	0.12–1.02	0.05	0.35	0.10–1.18	0.09
Spinal prosthesis	0.19	0.03–1.47	0.09	0.26	0.03–2.10	0.21
Previous bacteremia within 1 year	2.17	0.97–4.82	0.06	0.79	0.24–2.62	0.70
Fever	1.85	1.03–3.31	0.05	1.28	0.62–2.61	0.51
Severe sepsis	2.49	1.25–4.96	0.01	1.33	0.52–3.39	0.55
Preexisting or synchronous genitourinary tract infection	21.9	8.32–57.69	<0.01	19.23	6.51–56.83	<0.01
Preexisting or synchronous Intra-abdominal infection	41.63	5.1–339.67	<0.01	71.38	7.35–693.55	<0.01

CI, confidence interval; GNB, Gram-negative bacteria; OR, odds ratio