Wong Darren, Nielsen Travis B, Bonomo Robert A, Pantapalangkoor Paul, Luna Brian, Spellberg Brad
Division of Infectious Diseases, Keck School of Medicine of the University of Southern California (USC), Los Angeles, California, USA
Division of Infectious Diseases, Keck School of Medicine of the University of Southern California (USC), Los Angeles, California, USA.
Clin Microbiol Rev. 2017 Jan;30(1):409-447. doi: 10.1128/CMR.00058-16.
Acinetobacter is a complex genus, and historically, there has been confusion about the existence of multiple species. The species commonly cause nosocomial infections, predominantly aspiration pneumonia and catheter-associated bacteremia, but can also cause soft tissue and urinary tract infections. Community-acquired infections by Acinetobacter spp. are increasingly reported. Transmission of Acinetobacter and subsequent disease is facilitated by the organism's environmental tenacity, resistance to desiccation, and evasion of host immunity. The virulence properties demonstrated by Acinetobacter spp. primarily stem from evasion of rapid clearance by the innate immune system, effectively enabling high bacterial density that triggers lipopolysaccharide (LPS)-Toll-like receptor 4 (TLR4)-mediated sepsis. Capsular polysaccharide is a critical virulence factor that enables immune evasion, while LPS triggers septic shock. However, the primary driver of clinical outcome is antibiotic resistance. Administration of initially effective therapy is key to improving survival, reducing 30-day mortality threefold. Regrettably, due to the high frequency of this organism having an extreme drug resistance (XDR) phenotype, early initiation of effective therapy is a major clinical challenge. Given its high rate of antibiotic resistance and abysmal outcomes (up to 70% mortality rate from infections caused by XDR strains in some case series), new preventative and therapeutic options for Acinetobacter spp. are desperately needed.
不动杆菌是一个复杂的菌属，在历史上，对于多种菌种的存在一直存在混淆。这些菌种通常引起医院感染，主要是吸入性肺炎和导管相关菌血症，但也可引起软组织和尿路感染。越来越多的报告称不动杆菌属可引起社区获得性感染。不动杆菌的传播及其后续疾病的发生得益于该菌在环境中的顽强生存能力、对干燥的抵抗力以及对宿主免疫的逃避。不动杆菌属所表现出的毒力特性主要源于逃避先天免疫系统的快速清除，从而有效地实现高细菌密度，进而引发脂多糖（LPS）-Toll样受体4（TLR4）介导的脓毒症。荚膜多糖是一种关键的毒力因子，可实现免疫逃避，而LPS则引发感染性休克。然而，临床结局的主要驱动因素是抗生素耐药性。给予最初有效的治疗是提高生存率的关键，可将30天死亡率降低三倍。遗憾的是，由于这种细菌具有极高耐药性（XDR）表型的频率很高，尽早开始有效治疗是一项重大的临床挑战。鉴于其高抗生素耐药率和糟糕的预后（在某些病例系列中，XDR菌株引起的感染死亡率高达70%），迫切需要针对不动杆菌属的新的预防和治疗方案。
