Table 1.

Distribution of antimicrobial resistance genes among the Enterobacteriaceae clinical isolates

		No. (%) of strains positive for the genes
		β-lactamase resistance genes											quinolone and aminoglycoside resistance genes
							AmpC							16S rRNA methylase			qepA	Qnr
Species	No. of strains	blaCTX-M-1 groupa	blaCTX-M-2 group	blaCTX-M-9 groupb	blaSHVc	blaTEM	blaCMY-1	blaCMY-2	blaDHA	blaACC	blaACT	blaFOX	aac(6′)-Ib-cr	armA	rmtB	rmtC	qnrA	qnrB	qnrC	qnrS
E. coli	15	12	0	3	1	13	0	0	2	0	0	0	3	0	0	0	0	0	2	0	2
K. pneumoniae	15	14	0	0	13	14	0	0	2	0	0	0	9	3	0	0	0	0	5	0	9
E. cloacae	5	4	0	0	4	5	0	0	0	0	0	0	3	2	0	0	0	0	2	0	4
C. freundii	3	3	0	0	1	2	0	0	0	0	0	0	2	0	0	0	0	0	3	0	0
P. mirabilis	1	1	0	0	0	1	0	0	0	0	0	0	1	0	0	0	0	0	0	0	1
Total	39	34 (87)	0 (0)	3 (8)	19 (49)	35 (90)	0 (0)	0 (0)	4 (10)	0 (0)	0 (0)	0 (0)	18 (46)	5 (13)	0 (0)	0 (0)	0 (0)	0 (0)	12 (31)	0 (0)	16d (41)

^aTwenty-four isolates with bla_CTX-M-15, six isolates with bla_CTX-M-3 and four isolates with bla_CTX-M-55.

^bTwo isolates with bla_CTX-M-14 and one isolate with bla_CTX-M-24.

^cSix isolates with bla_SHV-12, one isolate each with bla_SHV-28, bla_SHV-32 and bla_SHV-11, respectively, and 10 isolates with bla_SHV-1.

^dFour isolates also positive for qnrB.