scholarly journals Persistent Legionnaires’ Disease and Associated Antibiotic Treatment Engender a Highly Disturbed Pulmonary Microbiome Enriched in Opportunistic Microorganisms

mBio ◽  
2020 ◽  
Vol 11 (3) ◽  
Author(s):  
Ana Elena Pérez-Cobas ◽  
Christophe Ginevra ◽  
Christophe Rusniok ◽  
Sophie Jarraud ◽  
Carmen Buchrieser
Keyword(s):  
Antibiotic Treatment ◽  
Legionella Pneumophila ◽  
Antimicrobial Treatment ◽  
Resistant Bacteria ◽  
Marker Genes ◽  
Antibiotic Resistant ◽  
Content Type ◽  
Lung Microbiome ◽  
Long Term Treatment

ABSTRACT Despite the importance of pneumonia to public health, little is known about the composition of the lung microbiome during infectious diseases, such as pneumonia, and how it evolves during antibiotic therapy. To study the possible relation of the pulmonary microbiome to the severity and outcome of this respiratory disease, we analyzed the dynamics of the pathogen and the human lung microbiome during persistent infections caused by the bacterium Legionella pneumophila and their evolution during antimicrobial treatment. We collected 10 bronchoalveolar lavage fluid samples from three patients during long-term hospitalization due to pneumonia and performed a unique longitudinal study of the interkingdom microbiome, analyzing the samples for presence of bacteria, archaea, fungi, and protozoa by high-throughput Illumina sequencing of marker genes. The lung microbiome of the patients was characterized by a strong predominance of the pathogen, a low diversity of the bacterial fraction, and an increased presence of opportunistic microorganisms. The fungal fraction was more stable than the bacterial fraction. During long-term treatment, no genomic changes or antibiotic resistance-associated mutations that could explain the persistent infection occurred, according to whole-genome sequencing analyses of the pathogen. After antibiotic treatment, the microbiome did not recover rapidly but was mainly constituted of antibiotic-resistant species and enriched in bacteria, archaea, fungi, or protozoa associated with pathogenicity. The lung microbiome seems to contribute to nonresolving Legionella pneumonia, as it is strongly disturbed during infection and enriched in opportunistic and/or antibiotic-resistant bacteria and microorganisms, including fungi, archaea, and protozoa that are often associated with infections. IMPORTANCE The composition and dynamics of the lung microbiome during pneumonia are not known, although the lung microbiome might influence the severity and outcome of this infectious disease, similar to what was shown for the microbiome at other body sites. Here we report the findings of a comprehensive analysis of the lung microbiome composition of three patients with long-term pneumonia due to L. pneumophila and its evolution during antibiotic treatment. This work adds to our understanding of how the microbiome changes during disease and antibiotic treatment and points to microorganisms and their interactions that might be beneficial. In addition to bacteria and fungi, our analyses included archaea and eukaryotes (protozoa), showing that both are present in the pulmonary microbiota and that they might also play a role in the response to the microbiome disturbance.

scholarly journals Legionella pneumophila infection and antibiotic treatment engenders a highly disturbed pulmonary microbiome with decreased microbial diversity

2019 ◽  
Author(s):  
Ana Elena Pérez-Cobas ◽  
Christophe Ginevra ◽  
Christophe Rusniok ◽  
Sophie Jarraud ◽  
Carmen Buchrieser
Keyword(s):  
Antibiotic Treatment ◽  
Legionella Pneumophila ◽  
Severe Pneumonia ◽  
Resistant Bacteria ◽  
Rrna Gene ◽  
Microbial Composition ◽  
Bacterial Composition ◽  
Lung Microbiome ◽  
The Impact ◽  
Healthy Lung

ABSTRACTBackgroundLung microbiome analyses have shown that the healthy lung is not sterile but it is colonized like other body sites by bacteria, fungi and viruses. However, little is known about the microbial composition of the lung microbiome during infectious diseases such as pneumonia and how it evolves during antibiotic therapy. To better understand the impact of the composition of the pulmonary microbiome on severity and outcome of pneumonia we analysed the composition and evolution of the human lung microbiome during pneumonia caused by the bacterium Legionella pneumophila.ResultsWe collected 10 bronchoalveolar lavage (BAL) samples from three patients during long-term hospitalisation due to severe pneumonia and performed a longitudinal in-depth study of the composition of their lung microbiome by high-throughput Illumina sequencing of the 16S rRNA gene (bacteria and archaea), ITS region (fungi) and 18S rRNA gene (eukaryotes). We found that the composition of the bacterial lung microbiome during pneumonia is hugely disturbed containing a very high percentage of the pathogen, a very low bacterial diversity, and an increased presence of opportunistic microorganisms such as species belonging to Staphylococcaceae and Streptococcaceae. The microbiome of antibiotic treated patients cured from pneumonia represented a different perturbation state with a higher abundance of resistant bacteria (mainly Firmicutes) and a significantly different bacterial composition as that found in healthy individuals. In contrast, the mycobiome remains more stable during pneumonia and antimicrobial therapy. Interestingly we identified possible cooperation within and between both communities. Furthermore, archaea (Methanobrevibacter) and protozoa (Acanthamoeba and Trichomonas) were detected.ConclusionsBacterial pneumonia leads to a collapse of the healthy microbiome and a strongly disturbed bacterial composition of the pulmonary microbiome that is dominated by the pathogen. Antibiotic treatment allows some bacteria to regrow or recolonize the lungs but the restoration of a healthy lung microbiome composition is only regained a certain time after the antibiotic treatment. Archaea and protozoa should also be considered, as they might be important but yet overseen members of the lung microbiome. Interactions between the micro- and the mycobiome might play a role in the restoration of the microbiome and the clinical evolution of the disease.

Microbiological pattern of prosthetic hip and knee infections: a high-volume, single-centre experience in China

2021 ◽  
Author(s):  
Yali Yu ◽  
Yiyi Kong ◽  
Jing Ye ◽  
Aiguo Wang ◽  
Wenteng Si
Keyword(s):  
Antibiotic Treatment ◽  
Prolonged Treatment ◽  
Resistant Bacteria ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Musculoskeletal Infection ◽  
Gram Negative ◽  
Content Type ◽  
Empirical Antibiotic Treatment ◽  
Link Type

Introduction. Prosthetic joint infection (PJI) is a serious complication after arthroplasty, which results in high morbidity, prolonged treatment and considerable healthcare expenses in the absence of accurate diagnosis. In China, microbiological data on PJIs are still scarce. Hypothesis/Gap Statement. The incidence of PJI is increasing year by year, and the proportion of drug-resistant bacteria infection is nicreasing, which brings severe challenges to the treatment of infection. Aim. This study aimed to identify the pathogens in PJIs, multi-drug resistance, and evaluate the effect of the treatment regimen in patients with PJI. Methodology. A total of 366 consecutive cases of PJI in the hip or knee joint were admitted at the Orthopedic Surgery Center in Zhengzhou, China from January 2012 to December 2018. Infections were confirmed in accordance with the Infectious Diseases Society of America and the Musculoskeletal Infection Society (MSIS) criteria. Concurrently, patient demographic data, incidence and antibiotic resistance were investigated. Statistical differences were analysed using Fisher’s exact test or chi-square test. Results. Altogether, 318 PJI cases satisfying the inclusion criteria were enrolled in this study, including 148 with hip PJIs and 170 with knee PJIs. The average age of patients with hip PJIs was lesser than that of patients with knee PJIs (56.4 vs. 68.6 years). Meanwhile, coagulase-negative staphylococcus (CNS, n=81, 25.5 %) was the predominant causative pathogen, followed by Staphylococcus aureus (n=67, 21.1 %). Methicillin-resistant Staphylococcus (MRS) was identified in 28.9 % of PJI patients. In addition, fungus accounted for 4.8 % (n=15), non-tuberculosis mycobacterium accounted for 1.6 % (n=5), polymicrobial pathogens accounted for 21.7 % (n=69), and Gram-negative bacteria accounted for 7.9 % (n=25) of the total infections. The results of antibiotic susceptibility testing showed that gentamicin and clindamycin β-lactam antibiotics were poorly susceptible to Gram-positive isolates, but they were sensitive to rifampicin, linezolid and vancomycin. While antibiotics such as amikacin and imipenem were effective against Gram-negative bacteria, there was a high resistance rate of other pathogens to gentamicin, clindamycin and some quinolone antibacterial drugs. Empirical antibiotic treatment should combine vancomycin and cephalosporin, levofloxacin or clindamycin. When the pathogen is confirmed, the treatment should be individualized. Conclusions. The prevalence of culture-negative PJIs is still very high. Gram-positive bacteria are still the main type of pathogens that cause PJIs. Attention should be paid to the high incidence of MRS, such as MRSA and MR-CNS, among PJI patients. Empirical antibiotic treatment should cover Gram-positive isolates, especially Staphylococcus .

scholarly journals Stochastic Variation in Expression of the Tricarboxylic Acid Cycle Produces Persister Cells

mBio ◽  
2019 ◽  
Vol 10 (5) ◽  
Author(s):  
Eliza A. Zalis ◽  
Austin S. Nuxoll ◽  
Sylvie Manuse ◽  
Geremy Clair ◽  
Lauren C. Radlinski ◽  
...  
Keyword(s):  
Antibiotic Treatment ◽  
Bacterial Infections ◽  
Tricarboxylic Acid Cycle ◽  
Tricarboxylic Acid ◽  
Resistant Bacteria ◽  
Chronic Infections ◽  
Persister Cells ◽  
Stochastic Variation ◽  
Content Type ◽  
Atp Levels

ABSTRACT Chronic bacterial infections are difficult to eradicate, though they are caused primarily by drug-susceptible pathogens. Antibiotic-tolerant persisters largely account for this paradox. In spite of their significance in the recalcitrance of chronic infections, the mechanism of persister formation is poorly understood. We previously reported that a decrease in ATP levels leads to drug tolerance in Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. We reasoned that stochastic fluctuation in the expression of tricarboxylic acid (TCA) cycle enzymes can produce cells with low energy levels. S. aureus knockouts in glutamate dehydrogenase, 2-oxoketoglutarate dehydrogenase, succinyl coenzyme A (CoA) synthetase, and fumarase have low ATP levels and exhibit increased tolerance of fluoroquinolone, aminoglycoside, and β-lactam antibiotics. Fluorescence-activated cell sorter (FACS) analysis of TCA genes shows a broad Gaussian distribution in a population, with differences of over 3 orders of magnitude in the levels of expression between individual cells. Sorted cells with low levels of TCA enzyme expression have an increased tolerance of antibiotic treatment. These findings suggest that fluctuations in the levels of expression of energy-generating components serve as a mechanism of persister formation. IMPORTANCE Persister cells are rare phenotypic variants that are able to survive antibiotic treatment. Unlike resistant bacteria, which have specific mechanisms to prevent antibiotics from binding to their targets, persisters evade antibiotic killing by entering a tolerant nongrowing state. Persisters have been implicated in chronic infections in multiple species, and growing evidence suggests that persister cells are responsible for many cases of antibiotic treatment failure. New antibiotic treatment strategies aim to kill tolerant persister cells more effectively, but the mechanism of tolerance has remained unclear until now.

scholarly journals In VitroEffects of Novel Ruthenium Complexes in Neospora caninum and Toxoplasma gondii Tachyzoites

2013 ◽  
Vol 57 (11) ◽  
pp. 5747-5754 ◽  
Author(s):  
Fabienne Barna ◽  
Karim Debache ◽  
Carsten A. Vock ◽  
Tatiana Küster ◽  
Andrew Hemphill
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Toxoplasma Gondii ◽  
Neospora Caninum ◽  
Ruthenium Complexes ◽  
Term Treatment ◽  
Content Type ◽  
Transmission Electron ◽  
Long Term Treatment

ABSTRACTUpon the screening of 16 antiproliferative compounds againstToxoplasma gondiiandNeospora caninum, two hydrolytically stable ruthenium complexes (compounds 16 and 18) exhibited 50% inhibitory concentrations of 18.7 and 41.1 nM (T. gondii) and 6.7 and 11.3 nM (N. caninum). To achieve parasiticidal activity with compound 16, long-term treatment (22 to 27 days at 80 to 160 nM) was required. Transmission electron microscopy demonstrated the rapid impact on and ultrastructural alterations in both parasites. These preliminary findings suggest that the potential of ruthenium-based compounds should thus be further exploited.

scholarly journals Fighting Antibiotic-Resistant Klebsiella pneumoniae with “Sweet” Immune Targets

mBio ◽  
2018 ◽  
Vol 9 (3) ◽  
Author(s):  
Roberto Adamo ◽  
Immaculada Margarit
Keyword(s):  
Klebsiella Pneumoniae ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
Therapeutic Approaches ◽  
Antibiotic Resistant ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Surface Polysaccharides ◽  
Resistant Strains ◽  
Murine Monoclonal Antibodies

ABSTRACT Antibiotics and vaccines have greatly impacted human health in the last century by dramatically reducing the morbidity and mortality associated with infectious diseases. The recent challenge posed by the emergence of multidrug-resistant bacteria could possibly be addressed by novel immune prophylactic and therapeutic approaches. Among the newly threatening pathogens, Klebsiella pneumoniae is particularly worrisome in the nosocomial setting, and its surface polysaccharides are regarded as promising antigen candidates. The majority of Klebsiella carbapenem-resistant strains belong to the sequence type 158 (ST258) lineage, with two main clades expressing capsular polysaccharides CPS1 and CPS2. In a recent article, S. D. Kobayashi and colleagues (mBio 9:e00297-18, 2018, https://doi.org/10.1128/mBio.00297-18) show that CPS2-specific IgGs render ST258 clade 2 bacteria more sensitive to human serum and phagocytic killing. E. Diago-Navarro et al. (mBio 9:e00091-18, 2018, https://doi.org/10.1128/mBio.00091-18) generated two murine monoclonal antibodies recognizing distinct glycotopes of CPS2 that presented functional activity against multiple ST258 strains. These complementary studies represent a step toward the control of this dangerous pathogen.

scholarly journals HAMLET, a Protein Complex from Human Milk, Has Bactericidal Activity and Enhances the Activity of Antibiotics against Pathogenic Streptococci

2019 ◽  
Vol 63 (12) ◽  
Author(s):  
Feiruz Alamiri ◽  
Kristian Riesbeck ◽  
Anders P. Hakansson
Keyword(s):  
Human Milk ◽  
Bactericidal Activity ◽  
Combination Treatment ◽  
Bacterial Species ◽  
Penicillin G ◽  
Resistant Bacteria ◽  
Tumoricidal Activity ◽  
Antibiotic Resistant ◽  
Content Type ◽  
Transport Inhibitors

ABSTRACT HAMLET (human alpha-lactalbumin made lethal to tumor cells) is a protein-lipid complex derived from human milk that was first described for its tumoricidal activity. Later studies showed that HAMLET also has direct bactericidal activity against select species of bacteria, with highest activity against Streptococcus pneumoniae. Additionally, HAMLET in combination with various antimicrobial agents can make a broad range of antibiotic-resistant bacterial species sensitive to antibiotics. Here, we show that HAMLET has direct antibacterial activity not only against pneumococci but also against Streptococcus pyogenes (group A streptococci [GAS]) and Streptococcus agalactiae (group B streptococci [GBS]). As with pneumococci, HAMLET treatment of GAS and GBS resulted in depolarization of the bacterial membrane, followed by membrane permeabilization and death, which was able to be inhibited by calcium and sodium transport inhibitors. Treatment of clinical antibiotic-resistant isolates of S. pneumoniae, GAS, and GBS with sublethal concentrations of HAMLET in combination with antibiotics decreased the MICs of the antibiotics into the sensitive range. This effect could also be blocked by ion transport inhibitors, suggesting that HAMLET’s bactericidal and combination treatment effects used similar mechanisms. Finally, we show that HAMLET potentiated the effects of erythromycin against erythromycin-resistant bacteria more effectively than penicillin G potentiated killing bacteria resistant to erythromycin. These results show that HAMLET effectively (i) kills three different species of pathogenic streptococci by similar mechanisms and also (ii) potentiates the activities of macrolides and lincosamides more effectively than combination treatment with beta-lactams. These findings suggest a potential therapeutic role for HAMLET in repurposing antibiotics currently causing treatment failures in patients.

scholarly journals Novel Carbapenemases FLC-1 and IMI-2 Encoded by an Enterobacter cloacae Complex Isolated from Food Products

2019 ◽  
Vol 63 (6) ◽  
Author(s):  
Michael S. M. Brouwer ◽  
Kamaleddin H. M. E. Tehrani ◽  
Michel Rapallini ◽  
Yvon Geurts ◽  
Arie Kant ◽  
...  
Keyword(s):  
General Population ◽  
Enterobacter Cloacae ◽  
Hydrolytic Activity ◽  
Resistant Bacteria ◽  
Human Consumption ◽  
The Novel ◽  
Antibiotic Resistant ◽  
Content Type ◽  
Class A ◽  
Enterobacter Cloacae Complex

ABSTRACT Food for human consumption is screened widely for the presence of antibiotic-resistant bacteria to assess the potential for transfer of resistant bacteria to the general population. Here, we describe an Enterobacter cloacae complex isolated from imported seafood that encodes two carbapenemases on two distinct plasmids. Both enzymes belong to Ambler class A β-lactamases, the previously described IMI-2 and a novel family designated FLC-1. The hydrolytic activity of the novel enzyme against aminopenicillins, cephalosporins, and carbapenems was determined.

scholarly journals Therapeutic institutions of violence: conceptualising the biographical narratives of mental health service users/survivors accessing long term “treatment” in England

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Stephen J. Macdonald
Keyword(s):  
Mental Health ◽  
Family Members ◽  
Psychiatric Hospitals ◽  
Term Treatment ◽  
Service Users ◽  
Content Type ◽  
Criminal Violence ◽  
Long Term Treatment ◽  
Forms Of Violence

Purpose This paper aims to conceptualise the residential and psychiatric hospital as a space where criminality and social harms can emerge. Because of recent media scandals over the past 10 years concerning privately-owned hospitals, this study examines the lived experiences of service users/survivors, family members and practitioners to examine historic and contemporary encounters of distress and violence in hospital settings. Design/methodology/approach The study consists of 16 biographical accounts exploring issues of dehumanising and harmful practices, such as practices of restraint and rituals of coercive violence. A biographical methodology has been used to analyse the life stories of service users/survivors (n = 9), family members (n = 3) and professional health-care employees (n = 4). Service users/survivors in this study have experienced over 40 years of short-term and long-term periods of hospitalisation. Findings The study discovered that institutional forms of violence had changed after the deinstitutionalisation of care. Practitioners recalled comprehensive experiences of violence within historic mental hospitals, although violence that may be considered criminal appeared to disappear from hospitals after the Mental Health Act (1983). These reports of criminal violence and coercive abuse appeared to be replaced with dehumanising and harmful procedures, such as practices of restraint. Originality/value The data findings offer a unique interpretation, both historical and contemporary, of dehumanising psychiatric rituals experienced by service users/survivors, which are relevant to criminology and MAD studies. The study concludes by challenging oppressive psychiatric “harms” to promote social justice for service users/survivors currently being “treated” within the contemporary psychiatric system. The study intends to conceptualise residential and psychiatric hospitals as a space where criminality and social harms can emerge. The three aims of the study examined risk factors concerning criminality and social harms, oppressive and harmful practices within hospitals and evidence that violence occurs within these institutionalised settings. The study discovered that institutional forms of violence had changed after the deinstitutionalisation of care. These reports of violence include dehumanising attitudes, practices of restraint and coercive abuse.

scholarly journals New Zealand White Rabbits Effectively ClearBorrelia burgdorferiB31 despite the Bacterium’s FunctionalvlsEAntigenic Variation System

2019 ◽  
Vol 87 (7) ◽  
Author(s):  
Maliha Batool ◽  
Andrew E. Hillhouse ◽  
Yurij Ionov ◽  
Kelli J. Kochan ◽  
Fatemeh Mohebbi ◽  
...  
Keyword(s):  
New Zealand ◽  
Persistent Infection ◽  
Antigenic Variation ◽  
Surface Expression ◽  
The United States ◽  
Antimicrobial Treatment ◽  
Current Data ◽  
Content Type ◽  
Highly Evolved

ABSTRACTBorrelia burgdorferiis a tick-borne bacterium responsible for approximately 300,000 annual cases of Lyme disease (LD) in the United States, with increasing incidences in other parts of the world. The debilitating nature of LD is mainly attributed to the ability ofB. burgdorferito persist in patients for many years despite strong anti-Borreliaantibody responses. Antimicrobial treatment of persistent infection is challenging. Similar to infection of humans,B. burgdorferiestablishes long-term infection in various experimental animal models except for New Zealand White (NZW) rabbits, which clear the spirochete within 4 to 12 weeks. LD spirochetes have a highly evolved antigenic variationvlssystem, on the lp28-1 plasmid, where gene conversion results in surface expression of the antigenically variable VlsE protein. VlsE is required forB. burgdorferito establish persistent infection by continually evading otherwise potent antibodies. Since the clearance ofB. burgdorferiis mediated by humoral immunity in NZW rabbits, the previously reported results that LD spirochetes lose lp28-1 during rabbit infection could potentially explain the failure ofB. burgdorferito persist. However, the present study unequivocally disproves that previous finding by demonstrating that LD spirochetes retain thevlssystem. However, despite thevlssystem being fully functional, the spirochete fails to evade anti-Borreliaantibodies of NZW rabbits. In addition to being protective against homologous and heterologous challenges, the rabbit antibodies significantly ameliorate LD-induced arthritis in persistently infected mice. Overall, the current data indicate that NZW rabbits develop a protective antibody repertoire, whose specificities, once defined, will identify potential candidates for a much-anticipated LD vaccine.

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