目的调查耐药鲍氏不动杆菌p内酰胺酶基因的存在和变异情况,为临床资料提供参考依据。方法收集2011年1月-2011年12月ICU患者痰液标本中分离的耐药鲍氏不动杆菌共25株,用聚合酶链反应(PCR)的方法分析34种β-内酰胺酶基因和ISabal—OXA-23、ISabal-OXA-66连锁检测。结果25株耐药鲍氏不动杆菌共检出4种β-内酰胺酶基因:TEM、ADC、OXA-23群、oXA_51群,经进一步测序和比对,21株TEM基因阳性均为TE胆1型84.0%,23株0xA23群阳性均为OXA-23型92.0%;25株OXA-51群阳性均为OXA-66型100.0%,24株ADC基因阳性中20株为ADC-30型80.O%,1株为新变异型ADC-634.0%,3株序列相同的为新变异型ADC-6412.0%,ISabal-OXA-23连锁检测结果与OXA-23检测结果相同,即OXA-23阳性菌株均由ISabal介导;而ISabal—OXA-66连锁检测均为阴性,提示oxA-66阳性菌株均非ISabal介导。结论鲍氏不动杆菌对伊内酰胺类药物耐药主要与产TEM-1、OXA-23型、OXA-66型、ADC-30型基因相关;ADC基因存在新变异型ADC-63和ADC-64是国内外首次报道。
OBJECTIVE To investigate the distribution and variety of 13-1actamase genes in drug-resistant Acineto-bacter baumannii so as to provide evidence for the clinical data. METHODS Totally 25 strains of A. baumannii isolated from the sputum specimens of the ICU patients from Jan 2011 to Dec 2011 were collected, then the poly- merase chain reaction (PCR) was performed to detect 34 β-lactamase genes and analyze the linkage detection of ISabal-OXA-23 and ISabal-OXA-66. RESULTS Totally 4 β-lactamase genes have been detected from the 25 strains of A. baumannii, including TEM, ADC, OXA-23 group, and OXA-51 group; further sequencing and com- parison demonstrated that there were 21 (84.0%) strains with the TEM-1 tested positive, 23 (92.0%) strains with OXA-23 tested positive, and 25 (100.0%) strains with the OXA-66 tested positive. Of 24 strains with ADC gene tested positive, 20 strains were confirmed as ADC-30, accounting for 80.0%, 1 (4.0 %) strain confirmed as novel, variant type ADC-63, 3 (12.0 % ) strains confirmed as the novel variant type ADC-64. The result of linkage detection of ISabal-OXA-23 was identical to the result of OXA-23, so all the strains with OXA-23 gene tested positive were mediated by ISabal, however the ISabal-OXA-66 was tested negative for the linkage detection, indicating that none of the strains with OXA-66 tested positive were mediated by ISabal. CONCLUSION The drug resistance of the A. baumannii tothe β-lactams antibiotics is mainly related to the TEM-1, OXA-23, OXA-66,or ADC-30; the novel variant ADC genotypes, ADC-63 and ADC-64, are reported for the first time in the world.