JMI Laboratories, 345 Beaver Kreek Centre, Suite A, North Liberty, IA 52317, USA.
JMI Laboratories, 345 Beaver Kreek Centre, Suite A, North Liberty, IA 52317, USA.
Int J Antimicrob Agents. 2015 Jul;46(1):53-9. doi: 10.1016/j.ijantimicag.2015.02.022. Epub 2015 Apr 14.
Ceftazidime/avibactam consists of ceftazidime combined with the novel non-β-lactam β-lactamase inhibitor avibactam, which inhibits Ambler classes A, C and some D enzymes. Clinical isolates were collected from 71 US medical centres in 2012-2013 and were tested for susceptibility at a central laboratory by reference broth microdilution methods. Results for 4381 bacterial isolates from intensive care unit (ICU) patients as well as those from ventilator-associated pneumonia (VAP) (n=435) were analysed and compared with those of 14 483 organisms from non-ICU patients. β-Lactamase-encoding genes were evaluated for 966 Enterobacteriaceae by a microarray-based assay. Ceftazidime/avibactam was active against 99.8/100.0% of Enterobacteriaceae (MIC90, 0.25/0.25mg/L) from ICU/non-ICU patients (2948/10,872 strains), including isolates from VAP (99.1%), multidrug-resistant (MDR) strains (99.3%), extensively drug-resistant (XDR) strains (96.5%) and meropenem-non-susceptible strains (98.0%), at MICs of ≤8mg/L. Against Enterobacteriaceae, susceptibility rates for ceftazidime, piperacillin/tazobactam and meropenem (ICU/non-ICU) were 86.1/91.8%, 88.0/94.3% and 97.8/99.2%, respectively. Meropenem was active against 75.1/85.4% of MDR Enterobacteriaceae and 8.1/27.1% of XDR Enterobacteriaceae from ICU/non-ICU patients. When tested against Pseudomonas aeruginosa, ceftazidime/avibactam inhibited 95.6/97.5% of isolates from ICU/non-ICU (842/2240 isolates), 97.3% of isolates from VAP, 80.7% of ceftazidime-non-susceptible and 80.7% of MDR isolates at ≤8mg/L. Susceptibility rates for P. aeruginosa from ICU/non-ICU were 77.7/86.9% for ceftazidime, 71.2/82.2% for piperacillin/tazobactam and 76.6/84.7% for meropenem. In summary, lower susceptibility rates were observed among ICU compared with non-ICU isolates. Ceftazidime/avibactam exhibited potent activity against a large collection of Gram-negative organisms from ICU and non-ICU patients and provided greater coverage than currently available β-lactams.
头孢他啶/阿维巴坦由头孢他啶与新型非β-内酰胺β-内酰胺酶抑制剂阿维巴坦组成，可抑制 Ambler 分类 A、C 和部分 D 型酶。2012-2013 年，从美国 71 个医疗中心采集临床分离株，在中央实验室采用参考肉汤微量稀释法进行药敏试验。分析了重症监护病房（ICU）患者 4381 株和呼吸机相关性肺炎（VAP）患者 435 株分离菌的结果，并与非 ICU 患者 14483 株分离菌的结果进行了比较。采用基于微阵列的检测方法对 966 株肠杆菌科细菌的β-内酰胺酶编码基因进行了评估。头孢他啶/阿维巴坦对 ICU/非 ICU 患者（2948/10872 株）的肠杆菌科（MIC90，0.25/0.25mg/L）的活性为 99.8/100.0%，包括 VAP 分离株（99.1%）、多药耐药（MDR）株（99.3%）、广泛耐药（XDR）株（96.5%）和对美罗培南不敏感的株（98.0%），MIC 值≤8mg/L。对肠杆菌科，头孢他啶、哌拉西林/他唑巴坦和美罗培南（ICU/非 ICU）的药敏率分别为 86.1/91.8%、88.0/94.3%和 97.8/99.2%。美罗培南对 ICU/非 ICU 患者的 MDR 肠杆菌科细菌的活性为 75.1/85.4%，对 XDR 肠杆菌科细菌的活性为 8.1/27.1%。头孢他啶/阿维巴坦对铜绿假单胞菌的抑制率为 95.6/97.5%（ICU/非 ICU，842/2240 株），对 VAP 分离株的抑制率为 97.3%，对头孢他啶不敏感株和 MDR 株的抑制率为 80.7%，MIC 值均≤8mg/L。对 ICU/非 ICU 患者铜绿假单胞菌的药敏率分别为头孢他啶 77.7/86.9%、哌拉西林/他唑巴坦 71.2/82.2%和美罗培南 76.6/84.7%。总之，与非 ICU 分离株相比，ICU 分离株的药敏率较低。头孢他啶/阿维巴坦对 ICU 和非 ICU 患者的大量革兰阴性菌具有强大的活性，提供了比目前可用的β-内酰胺类药物更广泛的覆盖范围。
