Molecular Characterization of High and Low Virulent Escherichia coli Clinical Strains Isolated from Patients with Urinary Tract Infections with or without Bacteremia in Southern Taiwan

Figures & data

Figure 1 Flow chart of study design.

Table 1 Demographic Characteristics of the Study Patients and Isolated Strains

	All (n = 171)	Isolation site		P-value
		Blood (n=120)	Urine (n=51)
Gender				<0.001^¥
Male	36 (21.1%)	16 (13.3%)	20 (39.2%)
Age				0.490^¥
≧65 yr	104 (60.8%)	75 (62.5%)	29 (56.9%)
BMI				0.957^¥
<24	76 (44.4%)	54 (45.0%)	22 (43.1%)
≧24 and <27	44 (25.7%)	31 (25.8%)	13 (25.5%)
≧27	51 (29.8%)	35 (29.2%)	16 (31.4%)
Mean white blood cell (10^3/uL)	12.54±5.74	12.42±6.03	12.83±5.05	0.675*
Mean white blood cell group				0.907^¥
≦12,000	85 (49.7%)	60 (50.0%)	25 (49.0%)
>12,000	86 (50.3%)	60 (50.0%)	26 (51.0%)
Urine glucose				0.749^¥
Normal	129 (75.4%)	89 (74.2%)	40 (78.4%)
Trace (±)	14 (8.2%)	11 (9.2%)	3 (5.9%)
1+, 2+, 3+	28 (16.4%)	20 (16.7%)	8 (15.7%)
Hospital stay length (days)	8.98±4.03	9.52±4.14	7.73±3.46	0.007*
Charlson comorbidity index	4.53±3.06	4.76±3.12	4.00±2.88	0.139*
History of UTI				0.232^¥
Over one time	44 (25.7%)	34 (28.3%)	10 (19.6%)
Underlying disease
Diabetes mellitus	78 (45.6%)	57 (47.5%)	21 (41.2%)	0.448^¥
Hypertension	93 (54.4%)	72 (60%)	21 (41.2%)	0.024^¥
Acute kidney injury	23 (13.5%)	19 (15.8%)	4 (7.8%)	0.161^¥
Septic shock	42 (24.6%)	37 (30.8%)	5 (9.8%)	0.003^¥
Chronic kidney disease	37 (21.6%)	27 (22.5%)	10 (19.6%)	0.674^¥
Upper UTI	79 (46.2%)	60 (50.0%)	19 (37.3%)	0.126^¥
MDR	67 (39.2%)	42 (35.0%)	25 (49.0%)	0.086^¥
Phylogenetic group (bacteria)
A	10 (5.8%)	4 (3.3%)	6 (11.8%)	0.067^¥
B1	9 (5.3%)	8 (6.7%)	1 (2.0%)	0.283^¥
B2	118 (69.0%)	82 (68.3%)	36 (70.6%)	0.771^¥
D	34 (19.9%)	26 (21.7%)	8 (15.7%)	0.370^¥
B2+D	152 (88.9%)	108 (90.0%)	44 (86.3%)	0.478^¥
A+B1	19 (11.1%)	12 (10.0%)	7 (13.7%)	0.478^¥

Notes: *:T-test; ^¥:Chi-Square test or Fisher’s exact test.

Table 2 Prevalence of Virulent Factors Identified from Pathogenic Strains in UTI Infected Patients with or Without Bacteremia

	All (n = 171)	Isolation site		P-value
		Blood (n=120)	Urine (n=51)
Virulence genes
traT	116 (67.8%)	82 (68.3%)	34 (66.7%)	0.831^¥
cvaC	9 (5.3%)	5 (4.2%)	4 (7.8%)	0.454^¥
kpsMTII	116 (67.8%)	83 (69.2%)	33 (64.7%)	0.568^¥
kpsMTIII	1 (0.6%)	1 (0.8%)	0 (0%)	1.000^¥
rfc	17 (9.9%)	13 (10.8%)	4 (7.8%)	0.550^¥
fyuA	146 (85.4%)	99 (82.5%)	47 (92.2%)	0.102^¥
iutA	117 (68.4%)	81 (67.5%)	36 (70.6%)	0.691^¥
hlyA	38 (22.2%)	28 (23.3%)	10 (19.6%)	0.592^¥
cnf1	8 (4.7%)	4 (3.3%)	4 (7.8%)	0.241^¥
cdtB-A	N.D	N.D	N.D
cdtB-S	N.D	N.D	N.D
fimH	160 (93.6%)	111 (92.5%)	49 (96.1%)	0.509^¥
focG	15 (8.8%)	11 (9.2%)	4 (7.8%)	1.000^¥
sfaS	30 (17.5%)	19 (15.8%)	11 (21.6%)	0.367^¥
papAH	107 (62.6%)	77 (64.2%)	30 (58.8%)	0.509^¥
papC	105 (61.4%)	79 (65.8%)	26 (51.0%)	0.068^¥
papEF	103 (60.2%)	76 (63.3%)	27 (52.9%)	0.204^¥
papGI	N.D	N.D	N.D
papGII	86 (50.3%)	67 (55.8%)	19 (37.3%)	0.026^¥
papGIII	3 (1.8%)	1 (0.8%)	2 (3.9%)	0.212^¥
sfa/focDE	30 (17.5%)	15 (12.5%)	15 (29.4%)	0.008^¥
bmaE	N.D	N.D	N.D
afa/draBC	7 (4.1%)	4 (3.3%)	3 (5.9%)	0.427^¥
gafD	N.D	N.D	N.D
nfaE	N.D	N.D	N.D
ibeA	7 (4.5%)	5 (4.8%)	2 (3.9%)	1.000^¥
5 major groups
Adhesins	169 (98.8%)	118 (98.3%)	51 (100.0%)	1.000^¥
P fimbriae	123 (71.9%)	90 (75.0%)	33 (64.7%)	0.171^¥
M fimbriae	N.D	N.D	N.D
S and FIC fimbriae	51 (29.8%)	29 (24.2%)	22 (43.1%)	0.013^¥
Type I fimbriae	160 (93.6%)	111 (92.5%)	49 (96.1%)	0.509^¥
Dr-binding adhesin	7 (4.1%)	4 (3.3%)	3 (5.9%)	0.427^¥
N-acetyl D-glucosamine specific fimbriae	N.D	N.D	N.D
Non-fimbriae adhesin	N.D	N.D	N.D
Capsule	117 (68.4%)	84 (70.0%)	33 (64.7%)	0.496^¥
Iron acquisition system	157 (91.8%)	109 (90.8%)	48 (94.1%)	0.559^¥
Toxins	40 (23.4%)	28 (23.3%)	12 (23.5%)	0.978^¥
Invasins and protectin	123 (71.9%)	88 (73.3%)	35 (68.6%)	0.531^¥

Note: ^¥:Chi-Square test or Fisher’s exact test.

Abbreviations: N.D, Not-detected.

Table 3 Prevalence of Virulent Factors Identified from High/Low Pathogenic Strains in UTI Infected Patients with or without Bacteremia

All (n = 171)	Blood (n=120)		P-value	Urine (n=51)		P-value
	B2+D (n=108)	A+B1 (n=12)		B2+D (n=44)	A+B1 (n=7)
Virulence gene
Trat	75 (69.4%)	7 (58.3%)	0.516^¥	32 (72.7%)	2 (28.6%)	0.034^¥
Cvac	5 (4.6%)	0 (0%)	1.000^¥	2 (4.5%)	2 (28.6%)	0.086^¥
Kpsmtii	75 (69.4%)	7 (58.3%)	0.185^¥	31 (70.5%)	2 (28.6%)	0.082^¥
Kpsmtiii	1 (0.9%)	0 (0%)	1.000^¥	N.D.	N.D.
Rfc	8 (7.4%)	5 (41.7%)	0.003^¥	4 (9.1%)	0 (0%)	1.000^¥
Fyua	91 (84.3%)	8 (66.7%)	0.220^¥	43 (97.7%)	4 (57.1%)	0.006^¥
Iuta	76 (70.4%)	5 (41.7%)	0.056^¥	33 (75%)	3 (42.9%)	0.174^¥
Hlya	27 (25%)	1 (8.3%)	0.291^¥	10 (22.7%)	0 (0%)	0.320^¥
Cnf1	4 (3.7%)	0 (0%)	1.000^¥	4 (9.1%)	0 (0%)	1.000^¥
Cdtb-A	N.D.	N.D.		N.D.	N.D.
Cdtb-S	N.D.	N.D.		N.D.	N.D.
Fimh	100 (92.6%)	11 (91.7%)	1.000^¥	43 (97.7%)	6 (85.7%)	0.258^¥
Focg	11 (10.2%)	0 (0%)	0.600^¥	4 (9.1%)	0 (0%)	1.000^¥
Sfas	15 (13.9%)	4 (33.3%)	0.097^¥	10 (22.7%)	1 (14.3%)	1.000^¥
Papah	72 (66.7%)	5 (41.7%)	0.114^¥	27 (61.4%)	3 (42.9%)	0.427^¥
Papc	76 (70.4%)	3 (25%)	0.003^¥	26 (59.1%)	0 (0%)	0.004^¥
Papef	72 (66.7%)	4 (33.3%)	0.030^¥	26 (59.1%)	1 (14.3%)	0.042^¥
Papgi	N.D.	N.D.		N.D.	N.D.
papGII	64 (59.3%)	3 (25%)	0.023^¥	18 (40.9%)	1 (14.3%)	0.236^¥
papGIII	1 (0.9%)	0 (0%)	1.000^¥	2 (4.5%)	0 (0%)	1.000^¥
sfa/focDE	15 (13.9%)	0 (0%)	0.358^¥	11 (25%)	4 (57.1%)	0.174^¥
bmaE	N.D.	N.D.		N.D.	N.D.
afa/draBC	4 (3.7%)	0 (0%)	1.000^¥	3 (6.8%)	0 (0%)	1.000^¥
gafD	N.D.	N.D.		N.D.	N.D.
nfaE	N.D.	N.D.		N.D.	N.D.
ibeA	5 (5.1%)	0 (0%)	1.000^¥	2 (4.5%)	0 (0%)	1.000^¥
5 Major groups
Adhesins	106 (98.1%)	12 (100%)	1.000^¥	44 (100%)	7 (100%)
P fimbriae	85 (78.7%)	5 (41.7%)	0.010^¥	29 (65.9%)	4 (57.1%)	0.686^¥
M fimbriae	N.D.	N.D.		N.D.	N.D.
S and FIC fimbriae	25 (23.1%)	4 (33.3%)	0.481^¥	17 (38.6%)	5 (71.4%)	0.216^¥
Type I fimbriae	100 (92.6%)	11 (91.7%)	1.000^¥	43 (97.7%)	6 (85.7%)	0.258^¥
Dr-binding adhesin	4 (3.7%)	0 (0%)	1.000^¥	3 (6.8%)	0 (0%)	1.000^¥
N-acetyl D-glucosamine specific fimbriae	N.D.	N.D.		N.D.	N.D.
Non-fimbriae adhesin	N.D.	N.D.		N.D.	N.D.
Capsule	78 (72.2%)	6 (50%)	0.180^¥	31 (70.5%)	2 (28.6%)	0.082^¥
Iron acquisition system	100 (92.6%)	9 (75%)	0.080^¥	43 (97.7%)	5 (71.4%)	0.046^¥
Toxins	27 (25%)	1 (8.3%)	0.291^¥	12 (27.3%)	0 (0%)	0.177^¥
Invasins and protectin	80 (74.1%)	8 (66.7%)	0.731^¥	33 (75%)	2 (28.6%)	0.025^¥
Hospital stay length (days)	9.66±4.28	8.25±2.45	0.266*	7.45±2.91	9.43±5.94	0.481**
Charlson comorbidity index	4.79±3.1	4.50±3.42	0.762*	3.64±2.76	6.29±2.69	0.022*
Underlying Diseases (patients)
Diabetes mellitus	55 (50.9%)	2 (16.7%)	0.024^¥	17 (38.6%)	4 (57.1%)	0.427^¥
Hypertension	64 (59.3%)	8 (66.7%)	0.761^¥	15 (34.1%)	6 (85.7%)	0.015^¥
Acute kidney injury	18 (16.7%)	1 (8.3%)	0.688^¥	2 (4.5%)	2 (28.6%)	0.086^¥
Septic shock	36 (33.3%)	1 (8.3%)	0.102^¥	5 (11.4%)	0 (0%)	1.000^¥
Chronic kidney disease	25 (23.1%)	2 (16.7%)	1.000^¥	6 (13.6%)	4 (57.1%)	0.021^¥
Upper UTI	54 (50%)	6 (50%)	1.000^¥	19 (43.2%)	0 (0%)	0.037^¥
MDR	38 (35.2%)	4 (33.3%)	1.000^¥	22 (50%)	3 (42.9%)	1.000^¥

Notes: *:T-test; **:Mann–Whitney U-test; ^¥:Chi-Square test or Fisher’s exact test;

Abbreviation: ND, Not detected.

Table 4 Comparison of Virulence Scores Calculated from High/Low Pathogenic Strains in UTI Infected Patients with or Without Bacteremia

All (n = 171)	Isolation site					P value
	Blood(n=120)			Urine (n=51)
Virulence gene score	7.12±2.82			6.94±2.75		0.708*
Adhesins gene score	3.83±1.93			3.65±1.84		0.559*
Capsule gene score	0.70±0.46			0.65±0.48		0.499*
Iron acquisition system gene score	1.50±0.66			1.63±0.60		0.238*
Toxins score	0.27±0.51			0.27±0.53		0.928*
Invasins and protectin gene score	0.88±0.64			0.86±0.69		0.911*
High/Low virulent strains	B2+D (n=108)	A+B1 (n=12)	P value	B2+D (n=44)	A+B1 (n=7)	P value
Virulence gene score	7.33±2.70	5.17±3.24	0.011*	7.43±2.56	3.86±1.68	0.001*
Adhesin gene score	3.98±1.87	2.50±1.98	0.011*	3.86±1.88	2.29±0.76	0.035**
Capsule gene score	0.72±0.45	0.50±0.52	0.113*	0.70±0.46	0.29±0.49	0.031*
Iron acquisition system gene score	1.55±0.63	1.08±0.79	0.021*	1.73±0.50	1.00±0.82	0.002*
Toxins score	0.29±0.53	0.08±0.29	0.191**	0.32±0.56	0±0	0.120**
Invasins and protectin gene score	0.86±0.62	1.00±0.85	0.480*	0.91±0.64	0.57±0.98	0.235*

Notes: *:T-test; **:Mann–Whitney U-test.

Table 5 Characteristics of MDR and Non-MDR Strains Isolated from UTI Infected Patients with or Without Bacteremia

All (n = 171)	Drug resistance pattern					P value
	Non-MDR (n=104)			MDR (n=67)
Phylogenetic groups
A	7 (6.7%)			3 (4.5%)		0.742^¥
B1	5 (4.8%)			4 (6%)		0.739^¥
B2	70 (67.3%)			48 (71.6%)		0.550^¥
D	22 (21.2%)			12 (17.9%)		0.604^¥
B2+D	92 (88.5%)			60 (89.6%)		0.825^¥
A+B1	12 (11.5%)			7 (10.4%)		0.825^¥
Diseases
Diabetes mellitus	51 (49.0%)			27 (40.3%)		0.263^¥
Hypertension	57 (54.8%)			36 (53.7%)		1.000^¥
Acute kidney injury	7 (6.7%)			16 (23.9%)		0.001^¥
Septic shock	23 (22.1%)			19 (28.4%)		0.355^¥
Chronic kidney disease	25 (24.0%)			12 (17.9%)		0.342^¥
Upper UTI	44 (42.3%)			35 (52.2%)		0.204^¥
Bacteremia	78 (75.0%)			42 (62.7%)		0.086^¥
Hospital stay length (days)	8.35±3.58			9.97±4.49		0.010*
Charlson comorbidity index	4.75±3.19			4.19±2.85		0.248*
Virulence scores
Virulence gene score	7.34±2.68			6.64±2.93		0.112*
Adhesin gene score	3.97±1.86			3.48±1.93		0.097*
Capsule gene score	0.74±0.44			0.60±0.49		0.050**
Iron acquisition system gene score	1.55±0.64			1.52±0.66		0.800*
Toxins score	0.21±0.43			0.36±0.62		0.159**
Invasins and protectin gene score	0.97±0.69			0.72±0.57		0.013*
	Blood (n=120)			Urine (n=51)
	Non-MDR (n=78)	MDR (n=42)	P value	Non-MDR (n=26)	MDR (n=25)	P value
Phylogenetic group
A	4 (5.1%)	0 (0%)	0.296^¥	3 (11.5%)	3 (12.0%)	1.000^¥
B1	4 (5.1%)	4 (9.5%)	0.448^¥	1 (3.8%)	0 (0%)	1.000^¥
B2	54 (69.2%)	28 (66.7%)	0.773^¥	16 (61.5%)	20 (80.0%)	0.148^¥
D	16 (20.5%)	10 (23.8%)	0.676^¥	6 (23.1%)	2 (8.0%)	0.248^¥
B2+D	70 (89.7%)	38 (90.5%)	1.000^¥	22 (84.6%)	22 (88.0%)	1.000^¥
A+B1	8 (10.3%)	4 (9.5%)	1.000^¥	4 (15.4%)	3 (12.0%)	1.000^¥
Diseases
Diabetes mellitus	38 (48.7%)	19 (45.2%)	0.716^¥	13 (50%)	8 (32.0%)	0.192^¥
Hypertension	48 (61.5%)	24 (57.1%)	0.639^¥	9 (34.6%)	12 (48.0%)	0.332^¥
Acute kidney injury	5 (6.4%)	14 (33.3%)	<0.001^¥	2 (7.7%)	2 (8.0%)	1.000^¥
Septic shock	20 (25.6%)	17 (40.5%)	0.093^¥	3 (11.5%)	2 (8.0%)	1.000^¥
Chronic kidney disease	20 (25.6%)	7 (16.7%)	0.261^¥	5 (19.2%)	5 (20.0%)	1.000^¥
Upper UTI	34 (43.6%)	26 (61.9%)	0.056^¥	10 (38.5%)	9 (36.0%)	0.856^¥
Hospital stay length (days)	8.88±3.76	10.69±4.59	0.022*	6.73±2.39	8.76±4.11	0.035*
Charlson comorbidity index	4.85±3.23	4.60±2.96	0.670*	4.46±3.11	3.52±2.58	0.247*
Virulence scores
Virulence gene score	7.38±2.74	6.62±2.93	0.157*	7.19±2.53	6.68±2.98	0.511*
Adhesins gene score	4.01±1.92	3.5±1.92	0.166*	3.85±1.69	3.44±2	0.437*
Capsule gene score	0.76±0.43	0.6±0.5	0.067**	0.69±0.47	0.6±0.5	0.500*
Iron acquisition system gene score	1.55±0.64	1.4±0.7	0.248*	1.54±0.65	1.72±0.54	0.283*
Toxins score	0.22±0.45	0.36±0.62	0.262**	0.19±0.4	0.36±0.64	0.393*
Invasins and protectin gene score	0.94±0.67	0.76±0.58	0.158*	1.08±0.74	0.64±0.57	0.023*

Notes: *:T-test; **:Mann–Whitney U-test; ^¥:Chi-Square test or Fisher’s exact test.