Tantisiriwat Woraphot, Buppanharun Jirawat, Ekpanyaskul Chatchai, Onruang Kwanchai, Yungyuen Thitiya, Kiratisin Pattarachai, Santiwatanakul Somchai
Department of Preventive Medicine, HRH Princess Maha Chakri Sirindhorn Medical Center, Faculty of Medicine, Srinakharinwirot University, Nakhon Nayok 26120, Thailand.
Department of Pathology, HRH Princess Maha Chakri Sirindhorn Medical Center, Faculty of Medicine, Srinakharinwirot University, Nakhon Nayok 26120, Thailand.
Antibiotics (Basel). 2022 May 30;11(6):732. doi: 10.3390/antibiotics11060732.
(1) Background: Resistant (PA) infections have limited treatment options. Data on the activity of ceftolozane-tazobactam (C-T) against PA in Thailand are limited. Objectives: The objective of this study was to identify the in vitro activity of C-T against general and resistant PA isolates from patients with real clinical infections from the HRH Princess Maha Chakri Sirindhorn Medical Center (MSMC) compared to other antibiotics and to study the resistant molecular patterns of those PA strains which were resistant to C-T. (2) Materials and Methods: This was an in vitro susceptibility study of 100 PA isolates plus an additional seven resistant PA isolates collected from MSMC patients. All PA isolates were tested with susceptibility broth (Sensititre™) and C-T minimal inhibitory concentration (MIC) test strips (Liofilchem, Roseto degli, Abruzzi, Italy). The C-T-resistant PA isolates were analyzed for six β-lactamase genes (, , , , and ) and the -1 gene. (3) Results: A total of 100 PA isolates were collected between January 2020 and January 2021 and between February 2021 and September 2021 for the additional 7 resistant isolates. There were 18 resistant PA isolates (6 MDR, 11 XDR and 1 pan-drug resistant isolate). The overall susceptibility of the initial 100 PA isolates and the 18 resistant PA isolates was 94% and 44.5%, respectively, for C-T. The C-T susceptibility rates for isolates non-susceptible to ceftazidime, piperacillin-tazobactam, carbapenems and antipseudomonal β-lactams were 65.5%, 69.7%, 50% and 44.5%, respectively. Among the 10 isolates which were resistant to C-T, there were only 3 isolates found to have the resistant gene, which included 1 for , 1 for and 1 for . (4) Conclusions: Although C-T was the best susceptibility antibiotic overall for PA isolates and MDR PA isolates at the MSMC, most of the XDR PA isolates and the PDR PA isolate were not susceptible to C-T. The mechanisms for C-T resistance involved multiple factors including the presence of , and .
(1) 背景：耐碳青霉烯类鲍曼不动杆菌（PA）感染的治疗选择有限。关于头孢他啶阿维巴坦（C-T）在泰国对PA活性的数据有限。目的：本研究的目的是确定C-T对来自诗琳通公主医疗中心（MSMC）有实际临床感染患者的普通PA分离株和耐药PA分离株的体外活性，并与其他抗生素进行比较，同时研究对C-T耐药的PA菌株的耐药分子模式。(2) 材料与方法：这是一项对100株PA分离株以及另外从MSMC患者中收集的7株耐药PA分离株的体外药敏研究。所有PA分离株均用药敏肉汤（Sensititre™）和C-T最低抑菌浓度（MIC）测试条（Liofilchem，意大利阿布鲁齐大区罗塞托德伊）进行测试。对耐C-T的PA分离株分析6种β-内酰胺酶基因（blaTEM、blaSHV、blaCTX-M、blaOXA-1、blaOXA-23和blaOXA-51）以及blaNDM-1基因。(3) 结果：在2020年1月至2021年1月期间共收集了100株PA分离株，另外7株耐药分离株于2021年2月至9月收集。有18株耐药PA分离株（6株多重耐药、11株广泛耐药和1株泛耐药分离株）。最初的100株PA分离株和18株耐药PA分离株对C-T的总体药敏率分别为94%和44.5%。对头孢他啶、哌拉西林他唑巴坦、碳青霉烯类和抗假单胞菌β-内酰胺类不敏感的分离株对C-T的药敏率分别为65.5%、69.7%、50%和44.5%。在对C-T耐药的10株分离株中，仅发现3株有耐药基因，其中blaCTX-M-15有1株，blaOXA-23有1株，blaNDM-1有1株。(4) 结论：尽管C-T是MSMC中PA分离株和多重耐药PA分离株总体上药敏最佳的抗生素，但大多数广泛耐药PA分离株和泛耐药PA分离株对C-T不敏感。C-T耐药机制涉及多种因素，包括blaCTX-M、blaOXA-23和blaNDM-1的存在。
