Huang L-Y, Chen T-L, Lu P-L, Tsai C-A, Cho W-L, Chang F-Y, Fung C-P, Siu L K
Graduate Institute of Medical Sciences, National Defence Medical Centre [corrected] Taipei, Taiwan.
Clin Microbiol Infect. 2008 Nov;14(11):1010-9. doi: 10.1111/j.1469-0691.2008.02077.x.
In this study, 283 multidrug-resistant Acinetobacter baumannii (MDR-AB) bloodstream isolates were collected between 1996 and 2004, from three teaching hospitals located in different regions of Taiwan. Susceptibility data showed that strains carrying class 1 integrons were significantly more resistant (p <0.01) to all tested antibiotics (except aztreonam and chloramphenicol) than strains lacking integrons, Seven types of gene cassette were identified among these strains, including two that have not been previously reported. The vast majority of the cassettes encoded aminoglycoside resistance genes, including aacA4, aacC1, aac(6')-II, aadA1, aadA2, aadA4 and aadDA1. Sixteen distinct ribotypes were identified in MDR-AB isolates carrying class 1 integrons. Only one strain was found to produce an extended-spectrum beta-lactamase, i.e. VEB-3. In the 18 imipenem-resistant strains, two carbapenenmase genes, bla(VIM-11) and bla(OXA-58), were found concomitantly in one isolate. An island-wide epidemic clone and an endemic clone from a hospital located in the northern region were identified by ribotyping. On the basis of the susceptibility data among the different ribogroups, the epidemic clone was associated more significantly with resistance to cefepime and ampicillin-sulbactam than was the endemic clone. In conclusion, the presence of class 1 integrons was significantly associated with resistance in MDR-AB, and the epidemic, class 1 integron-carrying MDR-AB clone was found to be widespread in Taiwan.
在本研究中，1996年至2004年期间从台湾不同地区的三家教学医院收集了283株耐多药鲍曼不动杆菌（MDR-AB）血流分离株。药敏数据显示，携带1类整合子的菌株对所有测试抗生素（除氨曲南和氯霉素外）的耐药性均显著高于缺乏整合子的菌株（p<0.01）。在这些菌株中鉴定出7种基因盒类型，其中包括两种以前未报道过的类型。绝大多数基因盒编码氨基糖苷类耐药基因，包括aacA4、aacC1、aac(6')-II、aadA1、aadA2、aadA4和aadDA1。在携带1类整合子的MDR-AB分离株中鉴定出16种不同的核糖体分型。仅发现1株产生超广谱β-内酰胺酶，即VEB-3。在18株耐亚胺培南菌株中，在1株分离株中同时发现了两种碳青霉烯酶基因bla(VIM-11)和bla(OXA-58)。通过核糖体分型鉴定出一个全岛流行克隆和一个来自北部地区一家医院的地方性克隆。根据不同核糖体分型组之间的药敏数据，流行克隆对头孢吡肟和氨苄西林-舒巴坦的耐药性比地方性克隆更显著。总之，1类整合子的存在与MDR-AB的耐药性显著相关，并且发现携带1类整合子的流行MDR-AB克隆在台湾广泛传播。
