染色体型AmpC酶在鲍氏不动杆菌烧伤患者分离株中流行

AmpC Enzyme Mediated by Chromosome Prevailed in Acinetobacter baumannii Strains Isolated from Burned Patients

目的分析鲍氏不动杆菌烧伤患者分离株的AmpC酶分布情况。方法测定20株分离自烧伤科的鲍氏不动杆菌对20种抗菌药物的敏感性,采用PCR方法进行了染色体型(ADC)和质粒型(DHA)2种AmpC酶基因检测,并对部分阳性产物进行基因测序。结果20株鲍氏不动杆菌烧伤患者分离株对β-内酰胺类抗菌药物耐药率除左氧氟沙星和头孢哌酮/舒巴坦外均>85%,PCR检测ADC基因19株(95%)呈阳性,而DHA基因均为阴性;部分ADC阳性产物经测序比对与ADC基因EF546445相同。结论鲍氏不动杆菌烧伤分离株对β-内酰胺类抗菌药物多药耐药非常严重,染色体型AmpC酶ADC在鲍氏不动杆菌烧伤患者分离株中流行。

OBJECTIVE To investigate the distribation of the AmpC enzyme in Acinetobacter baumannii isolated from burned patients. METHODS Susceptibility tests were used to detect antibiotic resistance to 20 kinds of antimicrobial drugs in 20 strains of A. baumannii isolated from burned patients, AmpC enzyme genes were detected by PCR and partial positive products were chosen to sequence. RESULTS Drug resistances to β-tactam antibiotics in 20 strains of A. baumannii isolated from burned patients had exceeded 85% except levofloxacin or cefoperazone/sulbactam. Of ADC genes 95 % were positive, but all DHA genes were negative. Through sequence and Blast analysis, partial ADC positive products were identical with that of EF546445. CONCLUSIONS The multidrug resistance of A. baumannii isolated from burned patients to β-lactam antibiotics is serious. AmpC enzyme mediated by chromosome, ADC, prevails in A. baumannii isolated from burned patients.