Faculty Opinions recommendation of Potent synergy and sustained bactericidal activity of a vancomycin-colistin combination versus multidrug-resistant strains of Acinetobacter baumannii.

Acinetobacter baumannii is increasingly recognized as an important multidrug-resistant nosocomial pathogen. Recent work has highlighted enhanced growth and heightened virulence in the presence of ethyl alcohols. As alcohol-based hand rubs (ABHRs) are extensively used in health care settings, the authors set out to determine whether the hand rubs could also influence the growth of prevalent multidrug-resistant strains circulating in UK hospitals. A significant increase in growth was observed when minimal media were supplemented with concentrations of 1 % and lower of four commercially available hand rubs. In addition, growth in ABHR-supplemented media resulted in secretion of proteins into the culture supernatant. One of these was identified as OmpA, which is recognized as having emulsifying activity, which could potentially confer enhanced pathogenicity to A. baumannii.

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Bactericidal activity of herbal volatile oil extracts against multidrug resistant Acinetobacter baumannii

Journal of Intercultural Ethnopharmacology ◽

10.5455/jice.20170411091159 ◽

2017 ◽

Vol 6 (2) ◽

pp. 1 ◽

Cited By ~ 4

Author(s):

Amornrat Intorasoot ◽

Piyaorn Chornchoem ◽

Siriwoot Sookkhee ◽

Sorasak Intorasoot

Keyword(s):

Acinetobacter Baumannii ◽

Bactericidal Activity ◽

Volatile Oil ◽

Multidrug Resistant

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Mortality Associated with Acinetobacter baumannii Complex Bacteremia among Patients with War-Related Trauma

Infection Control and Hospital Epidemiology ◽

10.1086/649220 ◽

2010 ◽

Vol 31 (1) ◽

pp. 92-94 ◽

Cited By ~ 16

Author(s):

Grace Kang ◽

Joshua D. Hartzell ◽

Robin Howard ◽

Robert N. Wood-Morris ◽

Mark D. Johnson ◽

...

Keyword(s):

Mortality Rate ◽

Acinetobacter Baumannii ◽

Young Patients ◽

Multidrug Resistant ◽

Low Risk ◽

Risk Of Death ◽

High Prevalence ◽

Acinetobacter Baumannii Complex ◽

Resistant Strains

We investigated the mortality associated with Adnetobacter baumannii complex bacteremia among a cohort of patients hospitalized for war-related trauma. Despite a high prevalence of multidrug-resistant strains, the 30-day mortality rate was 2%. For relatively young patients with war-related trauma, A. baumannii complex bacteremia appears to be associated with a low risk of death.

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The Capsular Polysaccharide of Acinetobacter baumannii Is an Obstacle for Therapeutic Passive Immunization Strategies

Infection and Immunity ◽

10.1128/iai.00591-17 ◽

2017 ◽

Vol 85 (12) ◽

Cited By ~ 14

Author(s):

Shun Xin Wang-Lin ◽

Ruth Olson ◽

Janet M. Beanan ◽

Ulrike MacDonald ◽

Joseph P. Balthasar ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Outer Membrane ◽

Bactericidal Activity ◽

Capsular Polysaccharide ◽

Rapid Development ◽

Outer Membrane Proteins ◽

Passive Immunization ◽

Clinical Isolates ◽

Content Type ◽

Resistant Strains

ABSTRACT Acinetobacter baumannii has become an important concern for human health due to rapid development and wide spread of antimicrobial-resistant strains and high mortality associated with the infection. Passive immunizations with antisera targeting outer membrane proteins (OMPs) have shown encouraging results in protecting mice from A. baumannii infection, but monoclonal anti-OMP antibodies have not been developed, and their potential therapeutic properties have not been explored. The goal of this report is to evaluate the antibacterial activity of monoclonal antibodies (MAbs) targeting outer membrane protein A (OmpA) of A. baumannii. Five anti-OmpA MAbs were developed using hybridoma technology and showed strong binding to strain ATCC 19606. However, low antibody binding was observed when they were tested against six clinical isolates, which included extensively drug-resistant strains. In contrast, high binding to an isogenic K1 capsule-negative mutant (AB307.30) was shown, suggesting that capsular polysaccharide mediated the inhibition of MAb binding to OmpA. Anti-OmpA MAbs increased the macrophage-mediated bactericidal activity of AB307.30 but failed to increase phagocytic killing of capsule-positive strains. Capsular polysaccharide was also protective against complement-mediated bactericidal activity in human ascites in the presence and absence of opsonization. Lastly, passive immunization with anti-OmpA MAbs did not confer protection against challenge with AB307-0294, the encapsulated parent strain of AB307.30, in a mouse sepsis infection model. These results reveal the important role of capsule polysaccharide in shielding OmpA and thereby inhibiting anti-OmpA MAb binding to clinical isolates. This property of capsule hindered the therapeutic utility of anti-OmpA MAbs, and it may apply to other conserved epitopes in A. baumannii.

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Multidrug Resistant Acinetobacter baumannii: Risk Factors for Appearance of Imipenem Resistant Strains on Patients Formerly with Susceptible Strains

PLoS ONE ◽

10.1371/journal.pone.0009947 ◽

2010 ◽

Vol 5 (4) ◽

pp. e9947 ◽

Cited By ~ 34

Author(s):

Jung-Jr Ye ◽

Ching-Tai Huang ◽

Shian-Sen Shie ◽

Po-Yen Huang ◽

Lin-Hui Su ◽

...

Keyword(s):

Risk Factors ◽

Acinetobacter Baumannii ◽

Multidrug Resistant ◽

Resistant Strains

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Association between antibiotic pressure and the risk of colonization/infection by multidrug-resistant Acinetobacter baumannii complex: a time series analysis

Revista Española de Quimioterapia ◽

10.37201/req/061.2021 ◽

2021 ◽

Author(s):

María Huertas Vaquero ◽

◽

María Ángeles Asencio Egea ◽

Rafael Carranza González ◽

Antonio Padilla Serrano ◽

...

Keyword(s):

Time Series ◽

Acinetobacter Baumannii ◽

Multidrug Resistant ◽

Acinetobacter Baumannii Complex ◽

Amoxicillin Clavulanate ◽

Resistant Strains ◽

Individual Use ◽

The Individual ◽

The Relationship ◽

Control Study

Introduction. To analyze the association between antibiotic pressure and the risk of colonization/infection by Acinetobacter baumannii complex (AB), evaluating both the individual and general prescriptions of antibiotics. Methods. This is an analytical, observational, case-control study on patients admitted to an Intensive Care Unit (ICU) during an AB outbreak (14 months). A five-year time series was constructed with the monthly incidence of cases of infection/colonization with strains of AB resistant to each antibiotic administered and with the monthly consumption of these antibiotics in the ICU. Results. We identified 40 patients either infected (23) or colonized (17) by AB and 73 controls. We found an epidemic multidrug-resistant clone of AB in 75% of cases. Risk factors associated with the development of AB infection/colonization were: greater use of medical instruments, the presence of a tracheostomy, cutaneous ulcers, surgical lesions and prior antibiotic therapies. The regression analysis of individual use of antibiotics showed that prior treatment with ceftazidime, ceftriaxone, amoxicillin/clavulanate, imipenem, levofloxacin, linezolid, and vancomycin was a risk factor for acquiring AB. ARIMA models showed that the relationship were greatest and statistically significant when the treatment occurred between 6 months (ceftazidime) and 9 months (imipenem and levofloxacin) prior. Conclusions. The dynamic and aggregate relationship between the incidence of infection/colonization by multidrug-resistant strains of AB and prior antibiotic treatment was statistically significant for intervals of 6 to 9 months.

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CsrA Coordinates Compatible Solute Synthesis in Acinetobacter baumannii and Facilitates Growth in Human Urine

Microbiology Spectrum ◽

10.1128/spectrum.01296-21 ◽

2021 ◽

Author(s):

Josephine Joy Hubloher ◽

Kim Schabacker ◽

Volker Müller ◽

Beate Averhoff

Keyword(s):

Acinetobacter Baumannii ◽

Multidrug Resistant ◽

Compatible Solute ◽

Human Pathogen ◽

Content Type ◽

Clinical Environments ◽

Resistant Strains ◽

Opportunistic Human Pathogen ◽

Mrna Binding ◽

Optimal Adaptation

The opportunistic human pathogen Acinetobacter baumannii has become one of the leading causes of nosocomial infections around the world due to the increasing prevalence of multidrug-resistant strains and their optimal adaptation to clinical environments and the human host. Recently, it was found that CsrA, a global mRNA binding posttranscriptional regulator, plays a role in osmotic stress adaptation, virulence, and growth on amino acids of A. baumannii AB09-003 and 17961.

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