Nosocomial transmission of CTX-M-2 beta-lactamase-producing Acinetobacter baumannii in a neurosurgery ward.
Nosocomial transmission of CTX-M-2 beta-lactamase-producing Acinetobacter baumannii in a neurosurgery ward.
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发表时间：
2004
影响因子：
9.4
通讯作者：
N. Nagano;Y. Nagano;C. Cordevant;N. Shibata;Y. Arakawa
中科院分区：
文献类型：
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作者：
N. Nagano;Y. Nagano;C. Cordevant;N. Shibata;Y. Arakawa
从日本某神经外科病房3例疑似医院感染患者的经气管吸入培养物中分离出3株耐头孢噻肟（CTX）鲍曼不动杆菌FM0209680、FM0300106和FM0301433。这些菌株的CTX mic均大于128微克/毫升，但当克拉维酸浓度为4微克/毫升时，CTX mic急剧降低。这些菌株对头孢曲松、头孢多肟和氨曲南也有耐药性，但对头孢他啶和亚胺培南敏感。通过偶联传递了对多种广谱β -内酰胺类药物的抗性谱。病例1即使在住院6个月后，给予亚胺培南、头孢他啶和左氧氟沙星也未能根除菌株FM0209680。病例2和病例3分别于入院后第6周分离到菌株FM0300106和FM0301433，然后对每位患者定殖3周。病例2经亚胺培南治疗成功根除FM0300106，同时继续给予亚胺培南预防肺炎。病例3因无肺炎症状而停用预防性抗菌治疗，停药后FM0301433消失。三株鲍曼不动杆菌均携带bla（CTX- m -2）基因，在双盘协同试验中，CTX和氮曲南圆盘周围生长抑制区出现菌落，表明这三株鲍曼不动杆菌可诱导产生β -内酰胺酶。核糖分型研究表明，这些菌株属于同一克隆谱系。鲍曼不动杆菌携带的质粒与以前在船桥医疗中心泌尿科病房分离的奇异变形杆菌菌株携带的质粒具有相同的限制性谱。
Three strains of cefotaxime (CTX)-resistant Acinetobacter baumannii, FM0209680, FM0300106, and FM0301433, were isolated from transtracheal aspirate cultures of three patients with probable nosocomial infections in a neurosurgery ward in Japan. The CTX MICs for these isolates were greater than 128 microg/ml but were drastically reduced in the presence of 4 microg of clavulanic acid per ml. These strains were also resistant to ceftriaxone, cefpodoxime, and aztreonam but were susceptible to ceftazidime and imipenem. The profile of resistance to various broad-spectrum beta-lactams was transferred by conjugation. Strain FM0209680 was not eradicated from case patient 1 by administration of imipenem, ceftazidime, and levofloxacin, even after a 6-month hospitalization period. Strains FM0300106 and FM0301433 were isolated from case patients 2 and 3 during the sixth week following admission, respectively, and then each patient was colonized for 3 weeks. Eradication of FM0300106 was successfully obtained from case patient 2 by imipenem treatment, while administration of imipenem was continued to prevent pneumonia. Prophylactic antimicrobial therapy was discontinued in case patient 3 because of the lack of pneumonic symptoms, and FM0301433 disappeared after the discontinuation of antimicrobial chemotherapy. All three strains carried the bla(CTX-M-2) gene, and the appearance of colonies in the growth-inhibitory zones around disks of CTX and aztreonam in double-disk synergy tests suggested inducible beta-lactamase production in these A. baumannii strains. The ribotyping investigation suggested that all these strains belong to the same clonal lineage. The plasmids harbored by A. baumannii had the same restriction profile as those harbored by Proteus mirabilis strains previously isolated in a urology ward of the Funabashi Medical Center.