Mortality and molecular epidemiology associated with extended-spectrum β-lactamase production in Escherichia coli from bloodstream infection

Figures & data

Table 1 Baseline characteristics of 1,098 patients with Escherichia coli BSI stratified by ESBL production

Parameter/category	ESBL-positive (n=115)	ESBL-negative (n=983)	P-value
Hospital-acquired BSI*	67 (58%)	382 (39%)	<0.001
Age, years	59 (44–71)	67 (54–75)	<0.001
Male*	74 (64%)	521 (53%)	0.018
In-house mortality*	30 (26%)	181 (18%)	0.076
Length of hospital stay, total days	27 (12–53)	15 (8–32)	<0.001
Length of stay before BSI onset, days	7 (0–20)	1 (0–10)	<0.001
Charlson comorbidity index	5 (3–8)	5 (3–8)	0.227
Myocardial infarct*	5 (4%)	28 (3%)	0.381
Congestive heart failure*	19 (17%)	148 (15%)	0.681
Peripheral vascular disease*	19 (17%)	83 (8%)	0.007
Cerebrovascular disease*	8 (7%)	56 (6%)	0.673
Dementia*	2 (2%)	21 (2%)	1.000
Chronic lung disease*	11 (10%)	109 (11%)	0.643
Rheumatic disease*	0	32 (3%)	0.050
Peptic ulcer*	6 (6%)	36 (4%)	0.436
Mild liver disease*	12 (10%)	121 (12%)	0.652
Diabetes without complication*	14 (12%)	192 (20%)	0.058
Diabetes with complication*	8 (7%)	62 (6%)	0.839
Renal disease*	55 (48%)	425 (43%)	0.372
Malign tumor*	25 (22%)	237 (24%)	0.644
Liver disease*	9 (8%)	70 (7%)	0.848
Metastasis*	14 (12%)	139 (14%)	0.577
HIV*	2 (2%)	9 (1%)	0.617
Hemiplegia*	5 (4%)	37 (4%)	0.795
Leukemia*	15 (13%)	85 (9%)	0.124
Lymphoma*	5 (4%)	66 (7%)	0.424

Notes:

* Categorical variables were tested using Fisher’s exact test, and are presented as number (percentage). Continuous variables were tested using the Wilcoxon rank-sum test, and are presented as medians (interquartile range).

Abbreviations: BSI, bloodstream infection; ESBL, extended-spectrum β-lactamase; HIV, human immunodeficiency virus.

Figure 1 (A–D) Distribution of genotypes and phylogenetic groups of 95 extended-spectrum β-lactamase (ESBL)-producing Escherichia coli isolates from patients with bloodstream infection. (A) ESBL genes in all 95 ESBL E. coli isolates (n=95); (B) phylogenetic groups of all 95 ESBL E. coli isolates; (C) phylogenetic groups of CTX-M-15 E. coli isolates (n=55); (D) phylogenetic groups of CTX-M-1 E. coli isolates (n=21).

Abbreviation: ESBL, extended-spectrum β-lactamase.

Table 2 Results of the multivariable regression analysis of risk factors for mortality in cases of Escherichia coli bloodstream infection (BSI)

Parameter	Odds ratio	95% confidence interval	P-value
Age	0.985	0.975–0.995	0.004
Charlson comorbidity index	1.303	1.238–1.372	<0.001
Length of stay before BSI onset	1.017	1.009–1.024	<0.001
Length of hospital stay after BSI	0.988	0.980–0.996	0.002