Table 3 Association between the minimal inhibitory concentrations (MIC) of Benzalkonium chloride and chlorhexidine with the presence of biocide resistance genes QacE∆1 and CepA in Klebsiella pneumoniae isolates

qacE∆1

positive

31

2

6.5

15

48.4

6

19.4

4

12.9

2

6.5

2

6.5

8.48

0.132

negative

19

0

0

9

47.4

10

52.6

-

-

-

-

-

-

cepA

positive

36

1

2.8

20

55.6

10

27.8

2

5.6

1

2.8

2

5.6

5.57

0.322

negative

14

1

7.1

4

28.6

6

42.9

2

14.3

1

7.1

-

-

Biocide resistance

genes

MIC of Chlorohexidine (µg/mL)

Total

isolates

(n = 50)

4

8

16

32

64

128

X2

p value

NO

%

NO

%

NO

%

NO

%

NO

%

NO

%

qacE∆1

positive

31

-

-

6

19.4

4

12.9

6

19.4

10

32.3

5

16.1

9.63

0.06

negative

19

1

5.3

-

-

1

5.3

1

5.3

11

57.9

5

26.3

cepA

positive

36

-

-

3

8.3

4

11.1

6

16.7

16

44.4

7

19.4

0.177

0.68

negative

14

1

7.1

3

21.4

1

7.1

1

7.1

5

35.7

3

21.4