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1.
MMWR Morb Mortal Wkly Rep ; 73(39): 883-887, 2024 Oct 03.
Article de Anglais | MEDLINE | ID: mdl-39361547

RÉSUMÉ

Ice machines can harbor water-related organisms, and the use of ice or tap water for clinical care activities has been associated with infections in health care settings. During 2021-2022, a total of 23 cases of infection by Burkholderia multivorans (sequence type ST659) were reported at two southern California hospitals and linked to contaminated ice and water from ice machines. In addition to these 23 cases, this report also includes 23 previously unreported cases of B. multivorans ST659 infections that occurred during 2020-2024: 13 at a northern California hospital, eight at a hospital in Colorado, and two additional cases at one of the southern California hospitals. The same brand of ice machine and brands of filters, descaling, and sanitizing products were used by all four hospitals; B. multivorans was isolated from samples collected from ice machines in two of the hospitals. Whole genome sequencing indicated that all clinical and ice machine isolates were highly genetically similar (0-14 single nucleotide variant differences across 81% of the selected reference genome). Recommendations from public health officials to halt the outbreak included avoiding ice and tap water during clinical care activities. An investigation is ongoing to determine possible sources of ice machine contamination. During outbreaks of water-related organisms in health care facilities, health care personnel should consider avoiding the use of tap water, including ice and water from ice machines, for patient care.


Sujet(s)
Infections à Burkholderia , Hôpitaux , Glace , Humains , Californie/épidémiologie , Colorado/épidémiologie , Hôpitaux/statistiques et données numériques , Infections à Burkholderia/épidémiologie , Microbiologie de l'eau , Adulte d'âge moyen , Adulte , Femelle , Mâle , Sujet âgé , Infection croisée/épidémiologie , Infection croisée/prévention et contrôle , Épidémies de maladies , Burkholderia cepacia complex/isolement et purification , Jeune adulte , Adolescent , Soins aux patients , Sujet âgé de 80 ans ou plus , Enfant , Contamination de matériel
2.
Clin Microbiol Rev ; 37(3): e0021521, 2024 Sep 12.
Article de Anglais | MEDLINE | ID: mdl-39158301

RÉSUMÉ

SUMMARYThis guidance presents recommendations for clinical microbiology laboratories for processing respiratory samples from people with cystic fibrosis (pwCF). Appropriate processing of respiratory samples is crucial to detect bacterial and fungal pathogens, guide treatment, monitor the epidemiology of cystic fibrosis (CF) pathogens, and assess therapeutic interventions. Thanks to CF transmembrane conductance regulator modulator therapy, the health of pwCF has improved, but as a result, fewer pwCF spontaneously expectorate sputum. Thus, the collection of sputum samples has decreased, while the collection of other types of respiratory samples such as oropharyngeal and bronchoalveolar lavage samples has increased. To optimize the detection of microorganisms, including Pseudomonas aeruginosa, Staphylococcus aureus, Haemophilus influenzae, and Burkholderia cepacia complex; other less common non-lactose fermenting Gram-negative bacilli, e.g., Stenotrophomonas maltophilia, Inquilinus, Achromobacter, Ralstonia, and Pandoraea species; and yeasts and filamentous fungi, non-selective and selective culture media are recommended for all types of respiratory samples, including samples obtained from pwCF after lung transplantation. There are no consensus recommendations for laboratory practices to detect, characterize, and report small colony variants (SCVs) of S. aureus, although studies are ongoing to address the potential clinical impact of SCVs. Accurate identification of less common Gram-negative bacilli, e.g., S. maltophilia, Inquilinus, Achromobacter, Ralstonia, and Pandoraea species, as well as yeasts and filamentous fungi, is recommended to understand their epidemiology and clinical importance in pwCF. However, conventional biochemical tests and automated platforms may not accurately identify CF pathogens. MALDI-TOF MS provides excellent genus-level identification, but databases may lack representation of CF pathogens to the species-level. Thus, DNA sequence analysis should be routinely available to laboratories for selected clinical circumstances. Antimicrobial susceptibility testing (AST) is not recommended for every routine surveillance culture obtained from pwCF, although selective AST may be helpful, e.g., for unusual pathogens or exacerbations unresponsive to initial therapy. While this guidance reflects current care paradigms for pwCF, recommendations will continue to evolve as CF research expands the evidence base for laboratory practices.


Sujet(s)
Mucoviscidose , Infections de l'appareil respiratoire , Manipulation d'échantillons , Humains , Mucoviscidose/microbiologie , Mucoviscidose/complications , Infections de l'appareil respiratoire/microbiologie , Infections de l'appareil respiratoire/diagnostic , Manipulation d'échantillons/méthodes , Manipulation d'échantillons/normes , Techniques microbiologiques/méthodes , Techniques microbiologiques/normes , Bactéries/isolement et purification , Bactéries/classification , Appareil respiratoire/microbiologie , Champignons/isolement et purification , Champignons/classification
3.
Appl Environ Microbiol ; 90(9): e0060924, 2024 09 18.
Article de Anglais | MEDLINE | ID: mdl-39109876

RÉSUMÉ

Nontuberculous mycobacteria (NTM) in drinking water are a significant public health concern. However, an incomplete understanding of the factors that influence the occurrence of NTM in drinking water limits our ability to characterize risk and prevent infection. This study sought to evaluate the influence of season and water treatment, distribution, and stagnation on NTM in drinking water. Samples were collected source-to-tap in a full-scale, chloraminated drinking water system approximately monthly from December 2019 to November 2020. NTM were characterized using culture-dependent (plate culture with matrix-assisted laser desorption ionization-time-of-flight mass spectrometry [MALDI-TOF MS] isolate analysis) and culture-independent methods (quantitative PCR and genome-resolved metagenomics). Sampling locations included source waters, three locations within the treatment plant, and five buildings receiving water from the distribution system. Building plumbing samples consisted of first draw, 5-min flush, and full flush cold-water samples. As the study took place during the COVID-19 pandemic, the influence of reduced water usage in three of the five buildings was also investigated. The highest NTM densities source-to-tap were found in the summer first draw building water samples (107 gene copies/L), which also had the lowest monochloramine concentrations. Flushing was found to be effective for reducing NTM and restoring disinfectant residuals, though flush times necessary to improve water quality varied by building. Clinically relevant NTM species, including Mycobacterium avium, were recovered via plate culture, with increased occurrence observed in buildings with higher water age. Four of five NTM metagenome-assembled genomes were identified to the species level and matched identified isolates.IMPORTANCENTM infections are increasing in prevalence, difficult to treat, and associated with high morbidity and mortality rates. Our lack of understanding of the factors that influence NTM occurrence in drinking water limits our ability to prevent infections, accurately characterize risk, and focus remediation efforts. In this study, we comprehensively evaluated NTM in a full-scale drinking water system, showing that various steps in treatment and distribution influence NTM presence. Stagnant building water contained the highest NTM densities source-to-tap and was associated with low disinfectant residuals. We illustrated the differences in NTM detection and characterization obtained from culture-based and culture-independent methods, highlighting the complementarity between these approaches. We demonstrated that focusing NTM mitigation efforts in building plumbing systems, which have the highest NTM densities source-to-tap, has potential for immediate positive effects. We also identified steps during treatment that increase NTM levels, which provides beneficial information for utilities seeking to reduce NTM in finished water.


Sujet(s)
Chloramines , Eau de boisson , Mycobactéries non tuberculeuses , Purification de l'eau , Eau de boisson/microbiologie , Mycobactéries non tuberculeuses/génétique , Mycobactéries non tuberculeuses/isolement et purification , Chloramines/pharmacologie , Alimentation en eau , Microbiologie de l'eau , Désinfectants/pharmacologie , Saisons
4.
Curr Microbiol ; 81(9): 273, 2024 Jul 17.
Article de Anglais | MEDLINE | ID: mdl-39017960

RÉSUMÉ

In pharmaceutical manufacturing, ensuring product safety involves the detection and identification of microorganisms with human pathogenic potential, including Burkholderia cepacia complex (BCC), Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica, Staphylococcus aureus, Clostridium sporogenes, Candida albicans, and Mycoplasma spp., some of which may be missed or not identified by traditional culture-dependent methods. In this study, we employed a metagenomic approach to detect these taxa, avoiding the limitations of conventional cultivation methods. We assessed the groundwater microbiome's taxonomic and functional features from samples collected at two locations in the spring and summer. All datasets comprised 436-557 genera with Proteobacteria, Bacteroidota, Firmicutes, Actinobacteria, and Cyanobacteria accounting for > 95% of microbial DNA sequences. The aforementioned species constituted less than 18.3% of relative abundance. Escherichia and Salmonella were mainly detected in Hot Springs, relative to Jefferson, while Clostridium and Pseudomonas were mainly found in Jefferson relative to Hot Springs. Multidrug resistance efflux pumps and BlaR1 family regulatory sensor-transducer disambiguation dominated in Hot Springs and in Jefferson. These initial results provide insight into the detection of specified microorganisms and could constitute a framework for the establishment of comprehensive metagenomic analysis for the microbiological evaluation of pharmaceutical-grade water and other non-sterile pharmaceutical products, ensuring public safety.


Sujet(s)
Bactéries , Nappe phréatique , Métagénomique , Bactéries/génétique , Bactéries/classification , Bactéries/isolement et purification , Nappe phréatique/microbiologie , Microbiote/génétique , Préparations pharmaceutiques , Métagénome , Microbiologie de l'eau
5.
Nat Commun ; 15(1): 4889, 2024 Jun 07.
Article de Anglais | MEDLINE | ID: mdl-38849369

RÉSUMÉ

Polymicrobial infection of the airways is a hallmark of obstructive lung diseases such as cystic fibrosis (CF), non-CF bronchiectasis, and chronic obstructive pulmonary disease. Pulmonary exacerbations (PEx) in these conditions are associated with accelerated lung function decline and higher mortality rates. Understanding PEx ecology is challenged by high inter-patient variability in airway microbial community profiles. We analyze bacterial communities in 880 CF sputum samples collected during an observational prospective cohort study and develop microbiome descriptors to model community reorganization prior to and during 18 PEx. We identify two microbial dysbiosis regimes with opposing ecology and dynamics. Pathogen-governed PEx show hierarchical community reorganization and reduced diversity, whereas anaerobic bloom PEx display stochasticity and increased diversity. A simulation of antimicrobial treatment predicts better efficacy for hierarchically organized communities. This link between PEx, microbiome organization, and treatment success advances the development of personalized clinical management in CF and, potentially, other obstructive lung diseases.


Sujet(s)
Mucoviscidose , Dysbiose , Microbiote , Expectoration , Mucoviscidose/microbiologie , Humains , Mâle , Expectoration/microbiologie , Études prospectives , Femelle , Résultat thérapeutique , Dysbiose/microbiologie , Adulte , Antibactériens/usage thérapeutique , Antibactériens/pharmacologie , Poumon/microbiologie , Évolution de la maladie , Broncho-pneumopathie chronique obstructive/microbiologie , Jeune adulte , Adolescent , Bactéries/classification , Bactéries/génétique , Bactéries/isolement et purification
6.
Water Res ; 257: 121702, 2024 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-38749337

RÉSUMÉ

While online monitoring of physicochemical parameters has widely been incorporated into drinking water treatment systems, online microbial monitoring has lagged behind, resulting in the use of surrogate parameters (disinfectant residual, applied dose, concentration × time, CT) to assess disinfection system performance. Online flow cytometry (online FCM) allows for automated quantification of total and intact microbial cells. This study sought to investigate the feasibility of online FCM for full-scale drinking water ozone disinfection system performance monitoring. A water treatment plant with high lime solids turbidity in the ozone contactor influent was selected to evaluate the online FCM in challenging conditions. Total and intact cell counts were monitored for 40 days and compared to surrogate parameters (ozone residual, ozone dose, and CT) and grab sample assay results for cellular adenosine triphosphate (cATP), heterotrophic plate counts (HPC), impedance flow cytometry, and 16S rRNA gene sequencing. Online FCM provided insight into the dynamics of the full-scale ozone system, including offering early warning of increased contactor effluent cell concentrations, which was not observed using surrogate measures. Positive correlations were observed between online FCM intact cell counts and cATP levels (Kendall's tau=0.40), HPC (Kendall's tau=0.20), and impedance flow cytometry results (Kendall's tau=0.30). Though a strong correlation between log intact cell removal and CT was not observed, 16S rRNA gene sequencing results showed that passage through the ozone contactor significantly changed the microbial community (p < 0.05). Potential causes of the low overall cell inactivation in the contactor and the significant changes in the microbial community after ozonation include regrowth in the later chambers of the contactor and varied ozone resistance of drinking water microorganisms. This study demonstrates the suitability of direct, online microbial analysis for monitoring full-scale disinfection systems.


Sujet(s)
Désinfection , Eau de boisson , Cytométrie en flux , Ozone , Purification de l'eau , Cytométrie en flux/méthodes , Désinfection/méthodes , Eau de boisson/microbiologie , Purification de l'eau/méthodes
7.
Microbiol Spectr ; 12(6): e0402123, 2024 Jun 04.
Article de Anglais | MEDLINE | ID: mdl-38661349

RÉSUMÉ

A collection of 161 Ralstonia isolates, including 90 isolates from persons with cystic fibrosis, 27 isolates from other human clinical samples, 8 isolates from the hospital environment, 7 isolates from industrial samples, and 19 environmental isolates, was subjected to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) identification and yielded confident species level identification scores for only 62 (39%) of the isolates, including four that proved misidentified subsequently. Whole-genome sequence analysis of 32 representative isolates for which no confident MALDI-TOF MS species level identification was obtained revealed the presence of seven novel Ralstonia species, including three and four that were isolated from cystic fibrosis or other human clinical samples, respectively, and provided the basis for updating an in-house MALDI-TOF MS database. A reanalysis of all mass spectra with the updated MALDI-TOF MS database increased the percentage of isolates with confident species level identification up to 77%. The antimicrobial susceptibility of 30 isolates mainly representing novel human clinical and environmental Ralstonia species was tested toward 17 antimicrobial agents and demonstrated that the novel Ralstonia species were generally multi-resistant, yet susceptible to trimethoprim/sulfamethoxazole, ciprofloxacin, and tigecycline. An analysis of genomic antimicrobial resistance genes in 32 novel and publicly available genome sequences revealed broadly distributed beta-lactam resistance determinants.IMPORTANCEThe present study demonstrated that a commercial matrix-assisted laser desorption/ionization time-of-flight mass spectrometry identification database can be tailored to improve the identification of Ralstonia species. It also revealed the presence of seven novel Ralstonia species, including three and four that were isolated from cystic fibrosis or other human clinical samples, respectively. An analysis of minimum inhibitory concentration values demonstrated that the novel Ralstonia species were generally multi-resistant but susceptible to trimethoprim/sulfamethoxazole, ciprofloxacin, and tigecycline.


Sujet(s)
Antibactériens , Tests de sensibilité microbienne , Ralstonia , Spectrométrie de masse MALDI , Spectrométrie de masse MALDI/méthodes , Humains , Ralstonia/effets des médicaments et des substances chimiques , Ralstonia/génétique , Ralstonia/isolement et purification , Ralstonia/classification , Antibactériens/pharmacologie , Mucoviscidose/microbiologie , Infections bactériennes à Gram négatif/microbiologie , Infections bactériennes à Gram négatif/traitement médicamenteux , Multirésistance bactérienne aux médicaments/génétique , Résistance bactérienne aux médicaments , Génome bactérien/génétique , Séquençage du génome entier
8.
Res Sq ; 2024 Mar 21.
Article de Anglais | MEDLINE | ID: mdl-38562856

RÉSUMÉ

Polymicrobial infection of the airways is a hallmark of obstructive lung diseases such as cystic fibrosis (CF), non-CF bronchiectasis, and chronic obstructive pulmonary disease. Pulmonary exacerbations (PEx) in these conditions are associated with accelerated lung function decline and higher mortality rates. An understanding of the microbial underpinnings of PEx is challenged by high inter-patient variability in airway microbial community profiles. We analyzed bacterial communities in 880 CF sputum samples and developed microbiome descriptors to model community reorganization prior to and during 18 PEx. We identified two microbial dysbiosis regimes with opposing ecology and dynamics. Pathogen-governed PEx showed hierarchical community reorganization and reduced diversity, whereas anaerobic bloom PEx displayed stochasticity and increased diversity. A simulation of antimicrobial treatment predicted better efficacy for hierarchically organized communities. This link between PEx type, microbiome organization, and treatment success advances the development of personalized clinical management in CF and, potentially, other obstructive lung diseases.

9.
Ann Am Thorac Soc ; 21(4): 595-603, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-37963297

RÉSUMÉ

Rationale: Rates of viral respiratory infection (VRI) are similar in people with cystic fibrosis (CF) and the general population; however, the associations between VRI and CF pulmonary exacerbations (PEx) require further elucidation.Objectives: To determine VRI prevalence during CF PEx and evaluate associations between VRI, clinical presentation, and treatment response.Methods: The STOP2 (Standardized Treatment of Pulmonary Exacerbations II) study was a multicenter randomized trial to evaluate different durations of intravenous antibiotic therapy for PEx. In this ancillary study, participant sputum samples from up to three study visits were tested for respiratory viruses using multiplex polymerase chain reactions. Baselines and treatment-associated changes in mean lung function (percent predicted forced expiratory volume in 1 s), respiratory symptoms (Chronic Respiratory Infection Symptom Score), weight, and C-reactive protein were compared as a function of virus detection. Odds of PEx retreatment within 30 days and future PEx hazard were modeled by logistic and Cox proportional hazards regression, respectively.Results: A total of 1,254 sputum samples from 621 study participants were analyzed. One or more respiratory viruses were detected in sputum samples from 245 participants (39.5%). Virus-positive participants were more likely to be receiving CF transmembrane conductance regulator modulator therapy (45% vs. 34%) and/or chronic azithromycin therapy (54% vs. 44%) and more likely to have received treatment for nontuberculous Mycobacterium infection in the preceding 2 years (7% vs. 3%). At study visit 1, virus-positive participants were more symptomatic (mean Chronic Respiratory Infection Symptom Score, 53.8 vs. 51.1), had evidence of greater systemic inflammation (log10 C-reactive protein concentration, 1.32 log10 mg/L vs. 1.23 log10 mg/L), and had a greater drop in percent predicted forced expiratory volume in 1 second from the prior 6-month baseline (5.8 vs. 3.6). Virus positivity was associated with reduced risk of future PEx (hazard ratio, 0.82; 95% confidence interval, 0.69-0.99; P = 0.034) and longer median time to next PEx (255 d vs. 172 d; P = 0.021) compared with virus negativity.Conclusions: More than one-third of STOP2 participants treated for a PEx had a positive test result for a respiratory virus with more symptomatic initial presentation compared with virus-negative participants, but favorable long-term outcomes. More refined phenotyping of PEx, taking VRIs into account, may aid in optimizing personalized management of PEx.Clinical trial registered with www.clinicaltrials.gov (NCT02781610).


Sujet(s)
Mucoviscidose , Infections de l'appareil respiratoire , Maladies virales , Virus , Humains , Mucoviscidose/complications , Mucoviscidose/épidémiologie , Mucoviscidose/diagnostic , Protéine C-réactive , Prévalence , Infections de l'appareil respiratoire/traitement médicamenteux , Infections de l'appareil respiratoire/épidémiologie , Infections de l'appareil respiratoire/diagnostic , Maladies virales/complications , Maladies virales/épidémiologie , Maladies virales/diagnostic , Antibactériens/usage thérapeutique
10.
J Cyst Fibros ; 2023 Nov 10.
Article de Anglais | MEDLINE | ID: mdl-37953182

RÉSUMÉ

BACKGROUND: Care guidelines for cystic fibrosis (CF) have been developed to enhance consistent care and to improve health outcomes. We determined if adherence to CF care guidelines predicted P. aeruginosa incidence rates (Pa-IR) at U.S. CF centers in 2018. METHODS: This cross-sectional CF Foundation Patient Registry study included 82 adult and 132 pediatric centers. Adherence to 12 guidelines was defined categorically (guideline met) or as a continuous measure (proportion of patients being treated/evaluated per guideline). Association of adherence to individual guidelines with Pa-IR, accounted for center and patient characteristics relevant to Pa-IR and were modeled using random forests and weighted-least-squares (WLS) analyses. RESULTS: The mean Pa-IR was 0.2 cases/patient-years at risk (SE 0.0074) for all centers combined. Guideline adherence was lowest for ≥4 bacterial cultures/year (54% of centers) and annual oral glucose tolerance test (OGTT) (48% of centers), and highest for annual non-tuberculous mycobacteria (NTM) sputum culture (98%). The mean number of guidelines met was 6.7 and higher for pediatric (7.3) than adult (5.6) centers, (p<0.001). The number of guidelines met correlated negatively with Pa-IR (ß=-0.007, p = 0.043). Macrolide prescription and annual OGTT per guideline were associated with lower and higher Pa-IR, respectively. Centers with lower center-wide lung function, higher proportion of pwCF with low body-mass index, and location in the Southwest had higher Pa-IR. CONCLUSION: Overall adherence to guidelines was high except for performing ≥4 bacterial cultures/year and OGTT. Higher Pa-IR was associated with center characteristics and lower guideline adherence. The lower Pa-IR with greater adherence to guidelines suggests that focusing on quality care can positively impact Pa-IR.

11.
Antimicrob Agents Chemother ; 67(11): e0049823, 2023 11 15.
Article de Anglais | MEDLINE | ID: mdl-37768313

RÉSUMÉ

The novel clinical-stage ß-lactam-ß-lactamase inhibitor combination, cefepime-taniborbactam, demonstrates promising activity toward many Gram-negative bacteria producing class A, B, C, and/or D ß-lactamases. We tested this combination against a panel of 150 Burkholderia cepacia complex (Bcc) and Burkholderia gladioli strains. The addition of taniborbactam to cefepime shifted cefepime minimum inhibitory concentrations toward the provisionally susceptible range in 59% of the isolates tested. Therefore, cefepime-taniborbactam possessed similar activity as first-line agents, ceftazidime and trimethoprim-sulfamethoxazole, supporting further development.


Sujet(s)
Burkholderia cepacia complex , Burkholderia gladioli , Mucoviscidose , Humains , États-Unis , Céfépime/pharmacologie , Antibactériens/pharmacologie , Mucoviscidose/microbiologie , Inhibiteurs des bêta-lactamases/pharmacologie , bêta-Lactamases , Tests de sensibilité microbienne
12.
bioRxiv ; 2023 Jul 25.
Article de Anglais | MEDLINE | ID: mdl-37546739

RÉSUMÉ

Polymicrobial infection of the airways is a hallmark of obstructive lung diseases such as cystic fibrosis (CF), non-CF bronchiectasis, and chronic obstructive pulmonary disease (COPD). Intermittent pulmonary exacerbations (PEx) in these conditions are associated with lung function decline and higher mortality rates. An understanding of the microbial underpinnings of PEx is challenged by high inter-patient variability in airway microbial community profiles. We analyzed 880 near-daily CF sputum samples and developed non-standard microbiome descriptors to model community reorganization prior and during 18 PEx. We identified two communal microbial regimes with opposing ecology and dynamics. Whereas pathogen-governed dysbiosis showed hierarchical community organization and reduced diversity, anaerobic bloom dysbiosis displayed stochasticity and increased diversity. Microbiome organization modulated the relevance of pathogens and a simulation of antimicrobial treatment predicted better efficacy for hierarchically organized microbiota. This causal link between PEx, microbiome organization, and treatment success advances the development of personalized dysbiosis management in CF and, potentially, other obstructive lung diseases.

13.
J Cyst Fibros ; 2023 May 25.
Article de Anglais | MEDLINE | ID: mdl-37244842

RÉSUMÉ

BACKGROUND: Home spirometry is increasingly used to monitor lung function in people with cystic fibrosis (pwCF). Although decreases in lung function in the setting of increased respiratory symptoms are consistent with a pulmonary exacerbation (PEx), the interpretation of home spirometry during asymptomatic periods of baseline health is unclear. The aims of this study were to determine the variation in home spirometry in pwCF during asymptomatic periods of baseline health and to identify associations between this variation and PEx. METHODS: Near-daily home spirometry measurements were obtained from a cohort of pwCF enrolled in a long-term study of the airway microbiome. Associations between the degree of variation in home spirometry and the time to next PEx were evaluated. RESULTS: Thirteen subjects (mean age of 29 years and mean percent predicted forced expiratory volume in one second [ppFEV1] of 60) provided a median of 204 spirometry readings taken during 40 periods of baseline health. The mean week-to-week within-subject level of variation in ppFEV1 was 15.2 ± 6.2%. The degree of variation in ppFEV1 during baseline health was not associated with time to PEx. CONCLUSIONS: Variation in ppFEV1 measured with near-daily home spirometry in pwCF during periods of baseline health exceeded the variation in ppFEV1 expected in clinic spirometry (based on ATS guidelines). The degree of variation in ppFEV1 during baseline health was not associated with time to PEx. These data are relevant for guiding interpretation of home spirometry.

14.
Transpl Infect Dis ; 25(2): e14041, 2023 Apr.
Article de Anglais | MEDLINE | ID: mdl-36864824

RÉSUMÉ

BACKGROUND: There is increased interest in bacteriophage (phage) therapy to treat infections caused by antibiotic-resistant bacteria. A lung transplant recipient with cystic fibrosis and Burkholderia multivorans infection was treated with inhaled phage therapy for 7 days before she died. METHODS: Phages were given via nebulization through the mechanical ventilation circuit. Remnant respiratory specimens and serum were collected. We quantified phage and bacterial deoxyribonucleic acid (DNA) using quantitative polymerase chain reaction, and tested phage neutralization in the presence of patient serum. We performed whole genome sequencing and antibiotic and phage susceptibility testing on 15 B. multivorans isolates. Finally, we extracted lipopolysaccharide (LPS) from two isolates and visualized their LPS using gel electrophoresis. RESULTS: Phage therapy was temporally followed by a temporary improvement in leukocytosis and hemodynamics, followed by worsening leukocytosis on day 5, deterioration on day 7, and death on day 8. We detected phage DNA in respiratory samples after 6 days of nebulized phage therapy. Bacterial DNA in respiratory samples decreased over time, and no serum neutralization was detected. Isolates collected between 2001 and 2020 were closely related but differed in their antibiotic and phage susceptibility profiles. Early isolates were not susceptible to the phage used for therapy, while later isolates, including two isolates collected during phage therapy, were susceptible. Susceptibility to the phage used for therapy was correlated with differences in O-antigen profiles of an early versus a late isolate. CONCLUSIONS: This case of clinical failure of nebulized phage therapy highlights the limitations, unknowns, and challenges of phage therapy for resistant infections.


Sujet(s)
Infections à Burkholderia , Burkholderia cepacia complex , Mucoviscidose , Phagothérapie , Femelle , Humains , Antibactériens/usage thérapeutique , Infections à Burkholderia/traitement médicamenteux , Mucoviscidose/microbiologie , ADN/usage thérapeutique , Hyperleucocytose/traitement médicamenteux , Lipopolysaccharides/usage thérapeutique , Poumon/microbiologie , Receveurs de transplantation , Issue fatale , Adulte
15.
Microbiol Spectr ; : e0410522, 2023 Feb 06.
Article de Anglais | MEDLINE | ID: mdl-36744887

RÉSUMÉ

Ralstonia insidiosa and Chryseobacterium gleum are bacterial species commonly found in potable water systems, and these two species contribute to the robustness of biofilm formation in a model six-species community from the International Space Station (ISS) potable water system. Here, we set about characterizing the interaction between these two ISS-derived strains and examining the extent to which this interaction extends to other strains and species in these two genera. The enhanced biofilm formation between the ISS strains of R. insidiosa and C. gleum is robust to starting inoculum and temperature and occurs in some but not all tested growth media, and evidence does not support a soluble mediator or coaggregation mechanism. These findings shed light on the ISS R. insidiosa and C. gleum interaction, though such enhancement is not common between these species based on our examination of other R. insidiosa and C. gleum strains, as well as other species of Ralstonia and Chryseobacterium. Thus, while the findings presented here increase our understanding of the ISS potable water model system, not all our findings are broadly extrapolatable to strains found outside of the ISS. IMPORTANCE Biofilms present in drinking water systems and terminal fixtures are important for human health, pipe corrosion, and water taste. Here, we examine the enhanced biofilm of cocultures for two very common bacteria from potable water systems: Ralstonia insidiosa and Chryseobacterium gleum. While strains originally isolated on the International Space Station show enhanced dual-species biofilm formation, terrestrial strains do not show the same interaction properties. This study contributes to our understanding of these two species in both dual-culture and monoculture biofilm formation.

16.
J Cyst Fibros ; 22(4): 623-629, 2023 07.
Article de Anglais | MEDLINE | ID: mdl-36628831

RÉSUMÉ

BACKGROUND: The progression of lung disease in people with cystic fibrosis (pwCF) has been associated with a decrease in the diversity of airway bacterial communities. How often low diversity communities occur in advanced CF lung disease and how they may be associated with clinical outcomes is not clear, however. METHODS: We sequenced a region of the bacterial 16S ribosomal RNA gene to characterize bacterial communities in sputum from 190 pwCF with advanced lung disease (FEV1≤40% predicted), with particular attention to the prevalence and relative abundance of dominant genera. We evaluated relationships between community diversity and clinical outcomes. RESULTS: Although most of the 190 pwCF with advanced lung disease had airway bacterial communities characterized by low diversity with a dominant genus, a considerable minority (40%) did not. The absence of a dominant genus, presence of methicillin-susceptible Staphylococcus aureus, and greater bacterial richness positively correlated with lung function. Higher relative abundance of the dominant genus and greater antimicrobial use negatively correlated with lung function. PwCF with a low diversity community and dominant genus had reduced lung transplant-free survival compared to those without (median survival of 1.6 vs 2.9 years). CONCLUSIONS: A considerable proportion of pwCF with advanced lung disease do not have airway bacterial communities characterized by low diversity and a dominant genus and these individuals had better survival. An understanding of the antecedents of low diversity airway communities- and the impact these may have on lung disease trajectory - may provide avenues for improved management strategies.


Sujet(s)
Mucoviscidose , Transplantation pulmonaire , Microbiote , Humains , Mucoviscidose/complications , Mucoviscidose/épidémiologie , Mucoviscidose/microbiologie , Poumon , Expectoration/microbiologie , Bactéries/génétique , ARN ribosomique 16S/génétique
17.
Antimicrob Agents Chemother ; 67(1): e0135222, 2023 01 24.
Article de Anglais | MEDLINE | ID: mdl-36507667

RÉSUMÉ

Burkholderia cepacia complex (Bcc) and Burkholderia gladioli are opportunistic human pathogens that are inherently multidrug resistant, limiting treatment options for infections. Here, a novel diazabicyclooctane, ETX0462, was evaluated for activity against Bcc and B. gladioli. Ninety-eight percent of the isolates examined in this study were susceptible. ETX0462 was found to demonstrate in vitro activity superior to that of currently available treatment options (e.g., trimethoprim-sulfamethoxazole and ceftazidime).


Sujet(s)
Infections à Burkholderia , Burkholderia cepacia complex , Burkholderia , Humains , Antibactériens/pharmacologie , Antibactériens/usage thérapeutique , Ceftazidime/usage thérapeutique , Association triméthoprime-sulfaméthoxazole/pharmacologie , Association triméthoprime-sulfaméthoxazole/usage thérapeutique , Infections à Burkholderia/traitement médicamenteux
18.
MMWR Morb Mortal Wkly Rep ; 71(48): 1517-1521, 2022 Dec 02.
Article de Anglais | MEDLINE | ID: mdl-36454695

RÉSUMÉ

In July 2021, the Virginia Department of Health notified CDC of a cluster of eight invasive infections with Burkholderia stabilis, a bacterium in the Burkholderia cepacia complex (BCC), among hospitalized patients at hospital A. Most patients had undergone ultrasound-guided procedures during their admission. Culture of MediChoice M500812 nonsterile ultrasound gel used in hospital A revealed contamination of unopened product with B. stabilis that matched the whole genome sequencing (WGS) of B. stabilis strains found among patients. CDC and hospital A, in collaboration with partner health care facilities, state and local health departments, and the Food and Drug Administration (FDA), identified 119 B. stabilis infections in 10 U.S. states, leading to the national recall of all ultrasound gel products produced by Eco-Med Pharmaceutical (Eco-Med), the manufacturer of MediChoice M500812. Additional investigation of health care facility practices revealed frequent use of nonsterile ultrasound gel to assist with visualization in preparation for or during invasive, percutaneous procedures (e.g., intravenous catheter insertion). This practice could have allowed introduction of contaminated ultrasound gel into sterile body sites when gel and associated viable bacteria were not completely removed from skin, leading to invasive infections. This outbreak highlights the importance of appropriate use of ultrasound gel within health care settings to help prevent patient infections, including the use of only sterile, single-use ultrasound gel for ultrasonography when subsequent percutaneous procedures might be performed.


Sujet(s)
Infections à Burkholderia , Épidémies de maladies , Contamination de matériel , Établissements de santé , Humains , Contamination de médicament , Échographie , États-Unis/épidémiologie , Gels , Infections à Burkholderia/épidémiologie , Infections à Burkholderia/étiologie
20.
J Pediatric Infect Dis Soc ; 11(Supplement_2): S46-S52, 2022 Sep 07.
Article de Anglais | MEDLINE | ID: mdl-36069902

RÉSUMÉ

Antimicrobial susceptibility testing (AST) has been used to guide therapy of airway infection in persons with cystic fibrosis (CF) for decades. However, evidence that AST adds benefit to treatment outcomes in CF is lacking. In fact, the routine use of AST has potential to exacerbate inappropriate antibiotic use. Several features of airway infection in CF contribute to the limitations of AST in predicting treatment outcomes, providing rationale for abandoning this practice altogether. Other features of CF infection suggest, however, that select use of AST can provide worthwhile guidance to antibiotic selection.


Sujet(s)
Mucoviscidose , Infections à Pseudomonas , Antibactériens/pharmacologie , Antibactériens/usage thérapeutique , Mucoviscidose/complications , Mucoviscidose/traitement médicamenteux , Humains , Tests de sensibilité microbienne , Infections à Pseudomonas/traitement médicamenteux , Pseudomonas aeruginosa
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