Antibiotic Resistance, Molecular Characteristics and Risk Factors of Carbapenem-Resistant Klebsiella pneumoniae in Clinical Isolates

Figures & data

Table 1 Clinical Patient Data

	N=62 (%)
Age(y)
Mean	69
Range	27–90
Gender(n)
Male	46(74.2%)
Female	16(25.8%)
Basic medical history(n)
Lung disease	33(53.2%)
Hypertension	32(51.6%)
Heart system disease	24(38.7%)
Cerebrovascular system disease	19(30.6%)
Kidney diseases	17(27.4%)
Department(n)
ICU	41(66.1%)
Haematology department	14(22.6%)
Cadre ward	2(3.2%)
Oncology department	1(1.6%)
Respiratory medicine	2(3.2%)
Neurology	2(3.2%)
Specimens(n)
Stool	20(32.3%)
Sputum	17(27.4%)
Blood	14(22.6%)
Sterile body fluids	7(11.3%)
Urine	3(4.8%)
Wound secretions	1(1.6%)
Invasive procedures(n)
Yes	39(62.9%)
No	23(37.1%)
Poor prognosis
Yes	40(64.5%)
No	22(35.5%)

Table 2 Antibiotic Sensitivity Results of CRKP Isolates

Antibiotics	Fold Point (µg/mL)		N=62 (Resistance Rate, %)
	Sensitive	Resistance
IPM	≤1	≥4	61 (98.4%)
MEM	≤1	≥4	62 (100%)
CAZ	≤4	≥16	62 (100%)
FEP	≤2	≥16	61 (98.4%)
ATM	≤4	≥16	57 (91.9%)
AMK	≤16	≥64	43 (69.4%)
TGC*	≤1	>2	54 (87.3%)
CIP	≤1	≥4	58 (93.5%)
LEV	≤2	≥8	60 (96.8%)
Col	≤2	≥4	8 (11.9%)
TOB	≤4	≥16	52 (83.9%)
TZP	≤16	≥128	62 (100%)
SXT	≤38	≥76	54 (87.1%)

Note: *Tigecycline MICs were interpreted using EUCAST MIC breakpoints.

Abbreviations: IPM, imipenem; Mem, meropenem; CAZ, ceftazidime; FEP, cefepime; ATM, aztreonam; AMK, amikacin; TGC, tigecycline; CIP, ciprofloxacin; LEV, levofloxacin; COL, colistin; SCF, cefoperazone-sulbactam; TOB, tobramycin; TZP, piperacillin-tazobactam; SXT, cotrimoxazole.

Figure 1 Antibiotic resistance rate of CRKP in ICU and general ward patients. *P<0.05, **P<0.01.

Table 3 The Positive Rate of Genes in 62 CRKP Isolates

Genes	Positive rate (%)
Carbapenemase gene
blaKPC	50 (80.6%)
blaNDM	8 (12.9%)
blaIMP	3 (4.8%)
blaKPC, blaNDM and blaIMP	1 (1.6%)
blaKPC and blaNDM	3 (4.84%)
blaOXA-48	0
blaSIM	0
blaVIM	0
blaGIM	0
Virulence gene
Uge	57 (91.9%)
WabG	58 (93.5%)
Ycf	60 (96.8%)
entB	60 (96.8%)
urea	60 (96.8%)
fimH	56 (90.3%)
ybtA	52 (83.9%)
iutA	48 (77.4%)
kfuB	9 (14.5%)
rmpA	23 (37.1%)
rmpA2	31 (50%)
aerobactin	0
magA	0
mrkD	0
wcaG	1 (1.6%)
iroN	1 (1.6%)
alls	1 (1.6%)
Capsular serotype
K5	1 (1.6%)

Table 4 Comparison of Molecular Types in Different Specimen Types

	Specimen			P^a	χ^2
	Sputum	Stool	Blood
blaKPC
Negative (%)	3 (17.7)	7 (35.0)	1 (7.1)	0.135	4.235
Positive (%)	14 (82.3)	13 (65.0)	13 (92.9)
blaNDM
Negative (%)	15 (88.2)	15 (75.0)	13 (92.9)	0.319	2.298
Positive (%)	2 (11.8)	5 (25.0)	1 (7.1)
rmpA
Negative (%)	11 (64.7)	12 (60.0)	5 (35.7)	0.229	2.966
Positive (%)	6 (35.3)	8 (40.0)	9 (64.3)
rmpA2
Negative (%)	6 (35.3)	10 (50.0)	4 (28.6)	0.417	1.758
Positive (%)	11 (64.7)	10 (50.0)	10 (71.4)

Note: ^aCalculated using the χ² test for categorical variables.

Table 5 Multivariate Analysis for Prognosis in CRKP-Infected Patients

Variable	P^a
Gender	0.410
ICU admission	0.071
blaKPC existence	0.663
Pulmonary disease	0.030*

Notes: ^aCalculated using a logistic regression model.; *P<0.05.