Clinical Characteristics And Risk Factors In Mixed-Enterococcal Bloodstream Infections

Figures & data

Figure 1 Flowchart of study participant enrollment.

Abbreviation: EBSI, enterococcal bloodstream infection.

Table 1 Demographic And Clinical Characteristics Of The Patients With Mono-EBSI Or Mixed-EBSI

Characteristics	Total (n=451)	Mono-EBSI (n =294)	Mixed-EBSI (n =157)	P-value
Age, median years (IQR)	63.0(50.0,72.0)	63.0(51.0,73.0)	61.0(47.0,71.0)	0.317
Male sex	320(71.0%)	212(72.1%)	108(68.8%)	0.460
Co-morbidities
Diabetes mellitus	73(16.2%)	44(15.0%)	29(18.0%)	0.336
Chronic kidney disease	29(6.4%)	20(6.8%)	9(5.7%)	0.659
Chronic liver disease	17(3.8%)	11(3.7%)	6(3.8%)	0.966
COPD or Severe asthma	27(6.0%)	19(6.5%)	8(5.1%)	0.560
Chronic cardiac insufficiency	38(8.4%)	26(8.8%)	12(7.6%)	0.662
Solid tumour	105(23.3%)	75(25.0%)	30(19.1%)	0.125
Trauma	88(19.5%)	45(15.3%)	43(27.4%)	0.002
Burn injury	29(6.4%)	7(2.4%)	22(14.0%)	<0.001
Cerebrovascular accident	69(15.3%)	45(15.3%)	24(15.3%)	0.996
CCI, median (IQR)	3(2,5)	4(2,5)	3(1,5)	0.089
APACHE II score, median (IQR)	16(11.21)	15(10.20)	18(13.22)	0.001
SOFA score, median (IQR)	5(4,9)	5(3,8)	6(4,9)	0.005
Pitt Bacteremia Score, median (IQR)	4(2,6)	3(1,5)	4(3,6)	<0.001
Hospitalization ward
Medical	41(9.1%)	29(9.9%)	12(7.6%)	0.435
Surgical	132(29.0%)	99(33.7%)	33(21.0%)	0.005
ICU	278(61.6%)	166(56.5%)	112(71.0%)	0.002
Previous treatment
Hyperalimentation	219(48.6%)	135(45.9%)	84(55.3%)	0.125
Mechanical ventilation	309(68.5%)	186(63.3%)	123(78.3%)	0.001
Antibiotic exposure	426(94.5%)	279(94.9%)	147(93.6%)	0.575
Surgery	222(49.2%)	139(47.3%)	83(52.9%)	0.258
Chemotherapy/radiation	11(2.4%)	6(2.0%)	5(3.2%)	0.453
Renal replacement therapy	38(8.4%)	25(8.5%)	13(8.3%)	0.935
Blood transfusion	49(10.9%)	24(8.2%)	25(15.9%)	0.012
Invasive devices
Central line	196(43.5%)	117(39.8%)	79(50.3%)	0.032
Indwelling urinary catheter	321(71.2%)	203(69.0%)	118(75.2%)	0.172
Intraperitoneal drainage	87(19.3%)	58(19.7%)	29(18.5%)	0.747
Prior hospital stay, median days (IQR)	9.0(4.0.19.0)	8.5(3.0.15.3)	12.0(5.0.21.0)	0.001
Nosocomial infection	396(87.8%)	253(86.1%)	143(91.1%)	0.120

Notes: Bold indicates P<0.05.

Abbreviations: COPD, chronic obstructive pulmonary disorder; CCI, Charlson Comorbidity Index; ICU, intensive care unit; APACHE, acute physiology and chronic health evaluation; SOFA, sequential organ failure assessment; IQR, interquartile range; EBSI, enterococcal bloodstream infections.

Table 2 Comparison Of Biological Indicators Between Groups Of Mixed-EBSI And Mono-EBSI

Biological Indicators	Total (n=451)	Mono-EBSI (n =294)	Mixed-EBSI (n =157)	P-value
Temperature (°C) (IQR)	39.0(38.4,39.3)	39(38.3,39.3)	39(38.5,39.5)	0.057
Blood routine test
WBC (×10^9/L) (IQR)	10.0(6.8,13.9)	10.0(7.1,14.0)	9.3(6.3,13.9)	0.215
Hematocrit (%) (IQR)	26.5(22.3,31.9)	27.1(22.3,32.4)	25.0(22.3,30.8)	0.068
Platelet (×10^9/L) (IQR)	156.0(101.1,246.0)	158.0(103.0,237.3)	155.0(98.0,254.5)	0.870
ANC (IQR)	8.46(5.51,12.33)	8.72(5.86,12.35)	7.59(5.15,12.25)	0.169
Liver and kidney function
Albumin (g/L) (mean±S.D.)	31.07±5.99	31.09±5.92	31.03±5.15	0.930
GPT (U/L) (IQR)	37.0(20.0,60.0)	34.5(19.0,63.3)	41.0(21.0,71.5)	0.227
GOT (U/L) (IQR)	37.0(26.0,75.0)	36.0(24.8,72.0)	39.0(18.8,81.0)	0.150
ALP (U/L) (IQR)	105.0(72.0,150.0)	108.0(71.8,153.5)	99.0(72.0,142.0)	0.394
γ-GT (U/L) (IQR)	47.0(25.0,105.0)	49.5(24.0,101.0)	47.0(27.0,113.0)	0.526
LDH (U/L) (IQR)	290.0(211.0,401.0)	283.0(210.8,385.3)	301.0(215.0,460.5)	0.267
TBil (μmol/L) (IQR)	16.5(10.5,30.5)	15.7(10.0,27.6)	17.8(11.9,33.3)	0.162
SCr (μmol/L) (IQR)	62.0(44.0,89.0)	62.5(44.0,88.0)	60.0(43.5,92.0)	0.725
PCT (ng/mL) (IQR)	0.53(0.20,2.00)	0.405(0.17,1.52)	0.76(0.26,3.52)	0.003

Notes: Bold indicates P<0.05.

Abbreviations: WBC, white blood count; ANC, absolute neutrophil count; GPT, glutamic-pyruvic transaminase; GOT, glutamic-oxaloacetic transaminase; ALP, alkaline phosphatase; γ-GT, gamma glutamyl transpeptidase; LDH, lactic dehydrogenase; TBil, total bilirubin; SCr, serum creatinine; PCT, procalcitonin; IQR, interquartile range; EBSI, enterococcal bloodstream infections.

Table 3 Multivariable Logistic Regression Of Factors Associated With Mixed-EBSI

Variable	Unadjusted OR (95% CI)	p-Value	Adjusted OR (95% CI)	p-Value
Trauma	2.09(1.30,3.35)	0.002	1.10(0.62,1.96)	0.742
Burn injury	6.68(2.79,16.02)	<0.001	7.39(2.69,20.28)	<0.001
APACHE II score	1.04(1.02,1.07)	0.003	1.03(0.98,1.09)	0.289
SOFA score	1.05(1.01,1.11)	0.032	0.97(0.89,1.06)	0.556
Pitt Bacteremia Score	1.15(1.07,1.24)	<0.001	1.09(0.95,1.26)	0.231
ICU stay	1.95(1.29,2.97)	0.002	0.98(0.42,2.30)	0.960
Surgical	0.52(0.33,0.83)	0.005	0.76(0.34,1.70)	0.499
Prior Blood transfusion	2.13(1.17,3.87)	0.013	1.26(0.63,2.53)	0.523
Central line	1.53(1.04,2.26)	0.032	0.89(0.55,2.342)	0.610
Mechanical ventilation	2.10(1.34,3.29)	0.001	1.13(0.54,2.34)	0.751
Prior hospital stay	1.01(1.00,1.02)	0.006	1.01(1.00,1.02)	0.026

Notes: Bold indicates P<0.05.

Abbreviations: ICU, intensive care unit; APACHE, acute physiology and chronic health evaluation; SOFA, sequential organ failure assessment; EBSI, enterococcal bloodstream infections.

Figure 2 The distribution comparison of enterococcus species isolated from mixed-EBSI and mono-EBSI.

Abbreviation: EBSI, enterococcal bloodstream infection.

Table 4 Comparison Of Microbiological Characteristics In Patients With Mono-EBSI Or Mixed-EBSI

	Total (n=451)	Mono-EBSI (n =294)	Mixed-EBSI (n =157)	P-value
Source of BSIs
Intra-abdominal	155(34.4%)	114(38.8%)	41(26.1%)	0.007
Primary BSI	130(28.8%)	84(28.6%)	46(29.3%)	0.871
Pneumonia	62(13.7%)	41(13.9%)	21(13.4%)	0.867
Skin and Soft tissue infection	43(9.5%)	17(5.8%)	26(16.6%)	<0.001
Central venous catheter	38(8.4%)	18(6.1%)	20(12.7%)	0.016
Urinary tract infection	12(2.7%)	9(3.1%)	3(1.9%)	0.470
Intracranial	5(1.1%)	5(1.7%)	0(0.0%)	0.168
Endocarditis	4(0.9%)	4(1.4%)	0(0.0%)	0.303
Others^a	2(0.4%)	2(0.7%)	0(0.0%)	0.545
Antibiotic resistance of Enterococcus^b
Ampicillin (285 vs. 154)^c	229(52.2%)	163(57.3%)	66(42.9%)	0.004
Ciprofloxacin (294 vs. 157)^c	255(56.5%)	172(58.5%)	83(52.9%)	0.250
Tetracycline (208 vs. 112)^c	156(48.8%)	93(44.7%)	63(56.2%)	0.049
Erythromycin (236 vs. 113)^c	249(71.3.0%)	172(72.9%)	77(68.1%)	0.359
Levofloxacin (235 vs. 121)^c	210(59.0%)	148(63.0%)	62(51.2%)	0.033
Nitrofurantoin (239 vs. 132)^c	115(31.8%)	84(35.1%)	31(25.2%)	0.054
Teicoplanin (57 vs. 43)^c	1(1.0%)	1(1.8%)	0(0.0%)	1
Linezolid (288 vs. 152)^c	71(16.1%)	41(14.2%)	30(19.7%)	0.136
Vancomycin (294 vs. 157)^c	10(2.2%)	8(2.7%)	2(1.3%)	0.505
Treatment after the onset of BSIs
Delayed antibiotic therapy	74(16.4%)	45(15.3%)	29(18.5%)	0.387

Notes: Bold indicates P<0.05; ^aSubmandibular gland, joint; ^bNot all agents listed tested in all isolates; ^cthe numbers in parentheses represent the total numbers of Enterococcus performed susceptibility test.

Abbreviation: EBSI, enterococcal bloodstream infections.

Table 5 Comparison Of Outcomes In Patients With Mono-EBSI Or Mixed-EBSI

Outcomes	Total (n=451)	Mono-EBSI (n =294)	Mixed-EBSI (n =157)	P-value
Total Hospitalization days(M) (IQR)	31.0(16.0,53.0)	29.0(16.0,49.0)	33.0(18.5,63.0)	0.031
Total ICU residence days(M)(IQR)	11.0(0.0,28.0)	9.0(0.0,25.0)	15.0(2.5,36.0)	<0.001
Septic shock (n,%)	106(23.5%)	56(19.0%)	50(31.8%)	0.002
7-day mortality (n,%)	72(16.0%)	44(15.0%)	28(17.8)	0.428
14-day mortality (n,%)	95(21.1%)	57(19.4%)	38(24.2%)	0.232
28-day mortality (n,%)	111(24.6%)	67(22.8%)	44(28.0%)	0.219
In-hospital mortality (n,%)	135(29.9%)	80(27.2%)	55(35.0%)	0.084

Notes: Bold indicates P<0.05.

Abbreviations: M, median; IQR, interquartile range; ICU, intensive care unit; EBSI, enterococcal bloodstream infections.

Figure 3 Kaplan-Meier estimates of survival in patients with mixed-enterococcal bloodstream infections and monomicrobial enterococcal bloodstream infections.

Abbreviation: EBSI, enterococcal bloodstream infection.