Clinical and Microbiological Characteristics of Klebsiella pneumoniae Bloodstream Infection in a Chinese Hospital: Hypervirulent and Multiclonal

Figures & data

Table 1 Microbiological Characteristics of K. pneumoniae Causing Bloodstream Infection

	No. (%) of Strains
	Total (n=66)	hvKP (n=29)	cKP (n=37)	P value^a
Age, median (IQR), y	63 (50–74)	58 (50–73)	64 (47–77)	0.936
Virulence genes
iucABCD cluster	29 (43.9)	29 (100)	0 (0)	<0.001
iroBCD cluster	35 (53.0)	25 (86.2)	10 (27.0)	<0.001
ybtS	36 (54.5)	21 (72.4)	15 (40.5)	<0.001
rmpA	34 (51.5)	26 (89.7)	8 (21.6)	<0.001
clbA	18 (27.3)	15 (51.7)	3 (8.1)	<0.001
allS	15 (22.7)	12 (41.4)	3 (8.1)	0.001
uge	65 (98.5)	28 (96.6)	37 (100)	0.439
wabG	56 (84.8)	25 (86.2)	31 (83.8)	>0.999
fimH	26 (39.4)	12 (41.4)	14 (37.8)	0.770
mrkD	65 (98.5)	28 (96.6)	37 (100)	0.439
String test
Positive	29 (43.9)	22 (75.9)	7 (18.9)	<0.001
Negative	37 (56.1)	7 (24.1)	30 (81.1)	<0.001
Serotypes
K1	14 (21.2)	12 (41.4)	2 (5.4)	<0.001
K2	12 (18.2)	9 (31.0)	3 (8.1)	0.017
K5	3 (4.5)	0 (0)	3 (8.1)	0.250
K20	1 (1.5)	1 (3.4)	0 (0)	0.439
K54	1 (1.5)	0 (0)	1 (2.7)	>0.999
K57	2 (3.0)	2 (6.9)	0 (0)	0.189
K-nontypable	33 (50.0)	5 (17.2)	28 (75.7)	<0.001

Notes: ^aP values indicate differences between hvKP and cKP. P < 0.05 was considered statistically significant.

Abbreviations: hvKP, hypervirulent K. pneumoniae; cKP, classic K. pneumoniae; IQR, interquartile range.

Table 2 Antimicrobial Susceptibility of Hypervirulent and Classic K. pneumoniae Causing BSI

	No. (%) of Susceptible Strains
	Total (n=66)	hvKP (n=29)	cKP (n=37)	P value^a
Cefotaxime	54 (81.8)	29 (100)	25 (67.6)	0.001
Ceftazidime	55 (83.3)	29 (100)	26 (70.3)	0.002
Cefepime	57 (86.4)	29 (100)	28 (75.7)	0.004
Aztreonam	58 (87.9)	29 (100)	29 (78.4)	0.007
Ampicillin-sulbactam	17 (77.3)	13 (96.6)	4 (62.2)	0.002
Amoxicillin-clavulanic acid	54 (81.8)	29 (100)	25 (67.6)	0.001
Piperacillin-tazobactam	58 (87.9)	29 (100)	29 (78.4)	0.007
Imipenem	63 (95.5)	29 (100)	34 (91.9)	0.25
Meropenem	63 (95.5)	29 (100)	34 (91.9)	0.25
Amikacin	64 (97.0)	29 (100)	35 (94.6)	0.50
Gentamicin	62 (93.9)	29 (100)	33 (89.2)	0.125
Ciprofloxacin	54 (81.8)	27 (93.1)	27 (73.0)	0.035
Levofloxacin	59 (89.4)	28 (96.6)	31 (83.8)	0.124
Chloramphenicol	55 (83.3)	25 (86.2)	30 (81.1)	0.743
Colistin	66 (100)	29 (100)	37 (100)	NA

Notes: ^aP values indicate differences between hvKP and cKP. P < 0.05 was considered statistically significant.

Abbreviations: BSI, bloodstream infection; hvKP, hypervirulent K. pneumoniae; cKP, classic K. pneumoniae; NA, not available.

Table 3 Clinical Characteristics of Patients with K. pneumoniae Bloodstream Infection

	No. (%) of Patients
	Total (n=66)	With hvKP (n =29)	With cKP (n =37)	P value^a
Age, median (IQR), y	63 (50–74)	58 (50–73)	64 (47–77)	0.936
Sex
Male	39 (59.1)	15 (51.7)	24 (64.9)	0.281
Female	27 (40.1)	14 (48.3)	13 (35.1)	0.281
Community-acquired	48 (72.7)	24 (82.8)	24 (64.9)	0.105
Hospital-acquired	18 (27.3)	5 (17.2)	13 (35.1)	0.105
Abscess	17 (25.8)	13 (44.8)	4 (10.8)	0.002
Liver abscess	14 (21.2)	12 (41.4)	2 (5.4)	<0.001
Skin abscess	1 (1.5)	1 (3.4)	0 (0)	0.439
Peripancreatic abscess	1 (1.5)	0 (0)	1 (2.7)	>0.999
Abdominal wall abscess	1 (1.5)	0 (0)	1 (2.7)	>0.999
Other types of infections
Pneumonia	26 (39.4)	10 (34.5)	16 (43.2)	0.470
Urinary tract infection	15 (22.7)	5 (17.2)	10 (27.0)	0.346
Abdominal infection	10 (15.2)	1 (3.4)	9 (24.3)	0.045
Skin and soft tissue infection	3 (4.5)	2 (6.9)	1 (2.7)	0.578
≥2 sites of infection	52 (78.8)	23 (79.3)	29 (78.4)	0.901
≥3 sites of infection	19 (28.8)	9 (31.0)	10 (27.0)	0.721
Underlying diseases
Diabetes	38 (57.6)	19 (65.5)	19 (51.4)	0.248
Hypertension	11 (16.7)	3 (10.3)	8 (21.6)	0.375
Coronary heart disease	7 (10.6)	4 (13.8)	3 (8.1)	0.690
Chronic kidney disease	6 (9.1)	3 (10.3)	3 (8.1)	>0.999
Cancer	15 (22.7)	5 (17.2)	10 (27.0)	0.346
Hospitalization in recent 90 days	19 (28.8)	3 (10.3)	16 (43.2)	0.003
ICU stay	20 (30.3)	9 (31.0)	11 (29.7)	0.909
Septic shock	18 (27.3)	7 (24.1)	11 (29.7)	0.613
Organ failure	14 (21.2)	5 (17.2)	9 (24.3)	0.485
Median duration of hospital stay (IQR)	22.3 (9–24.5)	15.5 (9–22)	27.8 (9.5–29.8)	0.138
Outcome
Discharged	54 (81.8)	25 (86.2)	29 (78.4)	0.413
Died	12 (18.2)	4 (13.8)	8 (21.6)	0.413
Readmitted in the following 90 days	13 (24.1)	6 (24.0)	7 (24.1)	0.858

Notes: ^aP values indicate differences between hvKP and cKP. P < 0.05 was considered statistically significant.

Abbreviations: hvKP, hypervirulent K. pneumoniae; cKP, classic K. pneumoniae; IQR, interquartile range; NT, not tested.