Table 2.

Detection of CTX-M-type extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae.

Locations	Participants	ESBL phenotypea		CTX-M geneb		CTX-M groupc
						CTX-M-1d		CTX-M-2e		CTX-M-8f		CTX-M-9g
Xintai	320	271	84.7%	251	78.4%	88	35.1%	0	0.0%	6	2.4%	170	67.7%
Ningyang	300	241	80.3%	207	69.0%	58	28.0%	0	0.0%	3	1.4%	133	64.3%
Total	620	512	82.6%	458	73.9%	146	31.9%	0	0.0%	9	1.9%	303	66.2%

^aESBL phenotype was determined according to CLSI recommendations.

^bCTX-M gene was determined by PCR.

^cGenotype of CTX-M genes was determined by PCR.

^dCTX-M-1 group includes CTX-M-1 and several other variants, such as CTX-M-3 and CTX-M-15.

^eCTX-M-2 group includes CTX-M-2 and several other variants.

^fCTX-M-8 group includes CTX-M-8 and several other variants.

^gCTX-M-9 group includes CTX-M-9 and several other variants, such as CTX-M-14.