Antimicrobial susceptibility of Acinetobacter clinical isolates and emerging antibiogram trends for nosocomial infection management

Abstract: Introduction: The drug resistant Acinetobacter strains are important causes of nosocomial infections that are difficult to control and treat. This study aimed to determine the antimicrobial susceptibility patterns of Acinetobacter strains isolated from different clinical specimens obtained from patients belonging to different age groups. METHODS: In total, 716 non-duplicate Acinetobacter isolates were collected from the infected patients admitted to tertiary-care hospitals at Lahore, Pakistan, over a period of 28 months. The Acinetobacter isolates were identified using API 20E, and antimicrobial susceptibility testing was performed and interpreted according to Clinical and Laboratory Standards Institute (CLSI) guidelines. RESULTS: The isolation rate of Acinetobacter was high from the respiratory specimens, followed by wound samples. Antibiotic susceptibility analyses of the isolates revealed that the resistance to cefotaxime and ceftazidime was the most common, in 710 (99.2%) specimens each, followed by the resistance to gentamicin in 670 (93.6%) isolates, and to imipenem in 651 (90.9%) isolates. However, almost all isolates were susceptible to tigecycline, colistin, and polymyxin B. CONCLUSIONS: The present study showed the alarming trends of resistance of Acinetobacter strains isolated from clinical specimens to the various classes of antimicrobials. The improvement of microbiological techniques for earlier and more accurate identification of bacteria is necessary for the selection of appropriate treatments.

摘要：
引言：耐药不动杆菌菌株是引发院内感染的重要致病菌，此类感染往往难以防控与治疗。本研究旨在明确从不同年龄段患者的不同临床标本中分离得到的不动杆菌菌株的抗菌药物敏感性谱。
材料与方法：本研究于巴基斯坦拉合尔的三级医院开展，历时28个月，共收集716株来自住院感染患者的非重复不动杆菌分离株。采用API 20E试剂盒对不动杆菌分离株进行鉴定，并依据美国临床和实验室标准协会（Clinical and Laboratory Standards Institute, CLSI）指南开展抗菌药物敏感性试验及结果判读。
结果：呼吸道标本的不动杆菌分离率最高，其次为伤口标本。对分离株的抗菌药物敏感性分析显示，对头孢噻肟与头孢他啶的耐药情况最为普遍，每类药物的耐药株数均为710株，占比99.2%；其次为庆大霉素耐药（670株，占比93.6%）与亚胺培南耐药（651株，占比90.9%）。然而，几乎所有分离株对替加环素（tigecycline）、粘菌素（colistin）以及多粘菌素B（polymyxin B）均敏感。
结论：本研究揭示了临床分离不动杆菌菌株对各类抗菌药物的耐药形势已十分严峻。为筛选合适的治疗方案，亟需优化微生物检测技术以实现细菌的早期精准鉴定。