Biology of Acinetobacter baumannii: Pathogenesis, Antibiotic Resistance Mechanisms, and Prospective Treatment Options

Abstract

Acinetobacter baumannii is undoubtedly one of the most successful pathogens responsible for hospital-acquired nosocomial infections in the modern healthcare system. Due to the prevalence of infections and outbreaks caused by multi-drug resistant A. baumannii, few antibiotics are effective for treating infections caused by this pathogen. To overcome this problem, knowledge of the pathogenesis and antibiotic resistance mechanisms of A. baumannii is important. In this review, we summarize current studies on the virulence factors that contribute to A. baumannii pathogenesis, including porins, capsular polysaccharides, lipopolysaccharides, phospholipases, outer membrane vesicles, metal acquisition systems, and protein secretion systems. Mechanisms of antibiotic resistance of this organism, including acquirement of β-lactamases, up-regulation of multidrug efflux pumps, modification of aminoglycosides, permeability defects, and alteration of target sites, are also discussed. Lastly, novel prospective treatment options for infections caused by multi-drug resistant A. baumannii are summarized.

Intensive care unit-acquired Acinetobacter baumannii infections in a Moroccan teaching hospital: epidemiology, risk factors and outcome

“…The following combination therapy: imipenem plus amikacin and moxifloxacin plus ceftriaxone were used for treatment of infections due to imipenem susceptible A. baumannii isolates. 30 Likewise, our study demonstrates that receiving antibiotic polytherapy independently increased the risk of A. baumannii infections by 11.8 times. Combination therapy leads to higher selective pressure of antibiotics on the gut flora than monotherapy and causes the proliferation of resistant strains.…”

Relationship between ultrasound bone parameters, lung function, and body mass index in healthy student population

“…Over the last decade, this bacterium has become one of the most prominent causes of hospital infections (1)(2)(3)(4). On 27 April 2017, the Web of Science TM listed 5,881 scientific reports (articles, books, reviews, and abstracts) published between 2010 and 2017 which had Acinetobacter baumannii in the title.…”

Correlation of Virulence Factors and Cell Adhesion of Clinical Isolates of Acinetobacter baumannii

“…Acinetobacter baumannii, recently emerged globally as an important nosocomial pathogen (5). Most of the strains are multidrug-resistant (MDR) with the ability to survive in the hospital environment and spread among patients (6)(7)(8). A. baumannii strains cause pneumonia, bacteremia, meningitis, and wound and urinary tract infections (7,9).…”

“…Most of the strains are multidrug-resistant (MDR) with the ability to survive in the hospital environment and spread among patients (6)(7)(8). A. baumannii strains cause pneumonia, bacteremia, meningitis, and wound and urinary tract infections (7,9). In order to determine the outcome of infections more attention should be paid to the interaction between A. baumannii and the host epithelial cells (4,10).…”