【摘要】 目的了解耐三代头孢菌素沙门菌的耐药基因分布特征,为疾病的防控和治疗提供依据。方法选取对头孢噻肟（CTX）和（或）头孢他啶（CAZ）耐药的临床分离的沙门菌157株,进行血清学分型和超广谱β-内酰胺酶（ESBLs）确证试验,采用PCR方法检测7种β-内酰胺类耐药基因。结果 157株沙门菌中,分布有20种血清型,以鼠伤寒沙门菌和肠炎沙门菌为主。共127株检出耐药基因,检出率为80.89%,包括bla_TEM103株、bla_CTX-M79株、bla_OXA-109株和bla_SHV1株,未检出bla_PER、bla_CMY和bla_ACC。ESBLs阳性80株,占50.96%;其中23株（28.75%）检出1种耐药基因,50株（62.50%）检出2种耐药基因,7株（8.75%）检出3种耐药基因;携带的耐药基因模式以bla_CTX-M-1G+bla_TEM（35株）、bla_CTX-M-9G+bla_TEM（14株）和bla_CTX-M-9G（12株）多见。ESBLs阴性77株,占49.04%;其中46株（59.74%）检出1种耐药基因,1株（1.30%）检出2种耐药基因,30株（38.96%）未检出耐药基因;携带的耐药基因模式以bla_TEM（46株）为主。对CTX耐药的沙门菌和对CTX不耐药的沙门菌bla_CTX-M的检出率差异有统计学意义（χ²=83.366,P=0.000）。对CAZ耐药的沙门菌和对CAZ不耐药的沙门菌bla_TEM检出率差异无统计学意义（χ²=0.268,P=0.384）。鼠伤寒沙门菌和肠炎沙门菌bla_CTX-M-1G和bla_CTX-M-9G的携带率差异有统计学意义（χ²=6.285,P=0.012;χ²=8.735,P=0.003）。bla_TEM在表型为CAZ耐药、CTX敏感或中介组,CTX耐药、CAZ敏感或中介组及CAZ和CTX均耐药组中的携带率差异无统计学意义（χ²=0.270,P=0.874）。结论耐三代头孢菌素沙门菌携带的耐药基因以bla_TEM和bla_CTX-M为主,同时伴有bla_OXA-10和bla_SHV,呈多样性,需要持续监测和研究。更多还原

【Abstract】 Objective To learn the distribution of drug resistance genes of the third-generation cephalosporin-resistant Salmonella to provide evidences for the prevention and treatment. Methods A total of 157 clinically isolated Salmonella strains resistant to cefotaxime（CTX） and/or ceftazidime（CAZ） were selected for serological typing and extended-spectrum β-lactamase（ESBLs） confirmation experiments,and then 7 genes resistant β-lactamase were detected by PCR. Results A total of 20 serotypes,mainly Salmonella typhimurium and Salmonella enteritidis,distributed among 157 strains of Salmonella. The resistance genes were detectable in 127 Salmonella strains with detection rate of 80.89%,including 103 strains of type bla_TEM,79 of bla_CTX-M,9 of bla_OXA-10 and 1 of bla_SHV,but no bla_PER,bla_CMYand bla_ACCwere detected. ESBLs were positive in 80 strains,accounting for 50.96%. One kind of resistance gene were detected in 23 strains（28. 75%）,2 kinds were detected in 50 strains（62. 50%） and 3 kinds were detected in 7 strains（8.75%）. The patterns of carried drug resistance gene were usually as bla_CTX-M-1G+ bla_TEM（n = 35）,bla_CTX-M-9G+ bla_TEM（n = 14） and bla_CTX-M-9G（n= 12）. ESBLs negative was confirmed in 77 strains,accounting for 49.04%,among them 46 strains carried one resistance gene（59.74%）,1 strain carried two resistance genes（1.30%） and 30 strains carried no resistance gene（38.96%）. The mode of carried resistance gene was mainly bla_TEM（n = 46）. The difference of the detection rate of bla_CTX-Mbetween the strains of Salmonella resistant to CTX and no resistant to CTX was statistically significant（χ²= 83.366,P = 0.000）. No statistically significant difference of the detection rate of bla_TEMbetween the stains of Salmonella resistant to CAZ and no resistant to CAZ was found（χ²= 0. 268,P =0.384）. The distribution of bla_CTX-M-1Gand bla_CTX-M-9Gbetween Salmonella typhimurium and Salmonella enteritidis was statistically different（χ²= 6.285,P = 0.012; χ²= 8.735,P = 0.003）. There was no statistically significant difference for the carrying rate of bla_TEMamong the phenotype of CAZ-resistant,CTX-sensitive or intermediary group,CTX-resistant,CAZ-sensitive or intermediary group and both CAZ and CTX-resistant groups（χ²= 0.270,P = 0.874）. Conclusion The third-generation cephalosporin-resistant Salmonella usually carried resistance genes bla_TEMand bla_CTX-M,as well as bla_OXA-10 and bla_SHV,showing diversity,which deserved continuous monitoring and inverstigation.更多还原