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Antimicrobial Agents and Chemotherapy Oct 2020is a genus of nonfermenting Gram-negative bacteria under order Although primarily isolated from respiratory tract of people with cystic fibrosis, spp. can cause a... (Review)
Review
is a genus of nonfermenting Gram-negative bacteria under order Although primarily isolated from respiratory tract of people with cystic fibrosis, spp. can cause a broad range of infections in hosts with other underlying conditions. Their rare occurrence and ever-changing taxonomy hinder defining their clinical features, risk factors for acquisition and adverse outcomes, and optimal treatment. spp. are intrinsically resistant to several antibiotics (e.g., most cephalosporins, aztreonam, and aminoglycosides), and are increasingly acquiring resistance to carbapenems. Carbapenem resistance is mainly caused by multidrug efflux pumps and metallo-β-lactamases, which are not expected to be overcome by new β-lactamase inhibitors. Among the other new antibiotics, cefiderocol, and eravacycline were used as salvage therapy for a limited number of patients with infections. In this article, we aim to give an overview of the antimicrobial resistance in species, highlighting the possible place of new antibiotics in their treatment.
Topics: Achromobacter; Anti-Bacterial Agents; Carbapenems; Drug Resistance, Multiple, Bacterial; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Humans
PubMed: 32816734
DOI: 10.1128/AAC.01025-20 -
The Ocular Surface Apr 2023Atypical microbial keratitis refers to corneal infections caused by micro-organisms not commonly encountered in clinical practice. Unlike infections caused by common... (Review)
Review
Atypical microbial keratitis refers to corneal infections caused by micro-organisms not commonly encountered in clinical practice. Unlike infections caused by common bacteria, cases of atypical microbial keratitis are often associated with worse clinical outcomes and visual prognosis. This is due to the challenges in the identification of causative organisms with standard diagnostic techniques, resulting in delays in the initiation of appropriate therapies. Furthermore, due to the comparatively lower incidence of atypical microbial keratitis, there is limited literature on effective management strategies for some of these difficult to manage corneal infections. This review highlights the current management and available evidence of atypical microbial keratitis, focusing on atypical mycobacteria keratitis, nocardia keratitis, achromobacter keratitis, and pythium keratitis. It will also describe the management of two uncommonly encountered conditions, infectious crystalline keratopathy and post-refractive infectious keratitis. This review can be used as a guide for clinicians managing patients with such challenging corneal infections.
Topics: Humans; Eye Infections, Bacterial; Keratitis; Bacteria
PubMed: 34768003
DOI: 10.1016/j.jtos.2021.11.001 -
Annals of the American Thoracic Society Feb 2015Achromobacteria are ubiquitous environmental organisms that may also become opportunistic pathogens in certain conditions, such as cystic fibrosis, hematologic and solid... (Review)
Review
Achromobacteria are ubiquitous environmental organisms that may also become opportunistic pathogens in certain conditions, such as cystic fibrosis, hematologic and solid organ malignancies, renal failure, and certain immune deficiencies. Some members of this genus, such as xylosoxidans, cause primarily nosocomially acquired infections affecting multiple organ systems, including the respiratory tract, urinary tract, and, less commonly, the cardiovascular and central nervous systems. Despite an increasing number of published case reports and literature reviews suggesting a global increase in achromobacterial disease, most clinicians remain uncertain of the organism's significance when clinically isolated. Moreover, effective treatment can be challenging due to the organism's inherent and acquired multidrug resistance patterns. We reviewed all published cases to date of non-cystic fibrosis achromobacterial lung infections to better understand the organism's pathogenic potential and drug susceptibilities. We found that the majority of these cases were community acquired, typically presenting as pneumonias (88%), and were most frequent in individuals with hematologic and solid organ malignancies. Our findings also suggest that achromobacterial lung infections are difficult to treat, but respond well to extended-spectrum penicillins and cephalosporins, such as ticarcillin, piperacillin, and cefoperazone.
Topics: Achromobacter; Age Factors; Anti-Bacterial Agents; Bronchiectasis; Cefoperazone; Cephalosporins; Community-Acquired Infections; Comorbidity; Drug Resistance, Bacterial; Female; Gram-Negative Bacterial Infections; Humans; Male; Neoplasms; Penicillins; Piperacillin; Pneumonia, Bacterial; Respiratory Tract Infections; Risk Factors; Sex Factors; Ticarcillin; Virulence Factors
PubMed: 25706494
DOI: 10.1513/AnnalsATS.201406-288FR -
Best Practice & Research. Clinical... 2017In the last decades some bacteria have been associated with a various extent with marginal zone (extra nodal, nodal and splenic types) lymphomas are frequently... (Review)
Review
In the last decades some bacteria have been associated with a various extent with marginal zone (extra nodal, nodal and splenic types) lymphomas are frequently associated with chronic infections, with important clinical, molecular, biological, and therapeutic implications. The well-known correlation between Helicobacter pylori and gastric MALT-lymphoma, the recently reported links between Chlamydia psittaci and ocular adnexal MALT-lymphoma and Borrelia burgdorferi and cutaneous MALT lymphoma constitute the most studied examples; in addition, Campylobacter jejuni and some more recent associations encompassing Achromobacter xylosoxidans and Haemophilus influenzae will be further reported. Biological and clinical features, therapeutic implications and future perspectives of these lymphoma-microbial associations are discussed in this review.
Topics: Bacteria; Bacterial Infections; Chronic Disease; Humans; Lymphoma, B-Cell, Marginal Zone
PubMed: 28288714
DOI: 10.1016/j.beha.2017.01.001 -
Viruses Jul 2023species colonization of Cystic Fibrosis respiratory airways is an increasing concern. Two adult patients with Cystic Fibrosis colonized by CF418 or CF116 experienced...
species colonization of Cystic Fibrosis respiratory airways is an increasing concern. Two adult patients with Cystic Fibrosis colonized by CF418 or CF116 experienced fatal exacerbations. spp. are naturally resistant to several antibiotics. Therefore, phages could be valuable as therapeutics for the control of . In this study, thirteen lytic phages were isolated and characterized at the morphological and genomic levels for potential future use in phage therapy. They are presented here as the Kumeyaay phage collection. Six distinct phage genome clusters were identified based on a comprehensive phylogenetic analysis of the Kumeyaay collection as well as the publicly available phages. The infectivity of all phages in the Kumeyaay collection was tested in 23 clinical isolates; 78% of these isolates were lysed by at least one phage. A cryptic prophage was induced in CF418 when infected with some of the lytic phages. This prophage genome was characterized and is presented as phage CF418-P1. Prophage induction during lytic phage preparation for therapy interventions require further exploration. Large-scale production of phages and removal of endotoxins using an octanol-based procedure resulted in a phage concentrate of 1 × 10 plaque-forming units per milliliter with an endotoxin concentration of 65 endotoxin units per milliliter, which is below the Food and Drugs Administration recommended maximum threshold for human administration. This study provides a comprehensive framework for the isolation, bioinformatic characterization, and safe production of phages to kill spp. in order to potentially manage Cystic Fibrosis (CF) pulmonary infections.
Topics: Adult; Humans; Bacteriophages; Cystic Fibrosis; Phylogeny; Achromobacter; Achromobacter denitrificans; Prophages; Endotoxins
PubMed: 37632008
DOI: 10.3390/v15081665 -
Microbiological Research Oct 2022Bacteria belonging to the genus Achromobacter are widely distributed in natural environments and have been recognized as emerging pathogens for their contribution to a... (Review)
Review
Bacteria belonging to the genus Achromobacter are widely distributed in natural environments and have been recognized as emerging pathogens for their contribution to a wide range of human infections. In particular, patients with cystic fibrosis (CF) are the subjects most frequently colonized by Achromobacter spp., which can cause persistent infections in their respiratory tract. Although many clinical aspects and pathogenic mechanisms still remain to be elucidated, Achromobacter spp. have been a source of expanding interest in recent years. This review examines the current literature regarding Achromobacter spp. role in CF, focusing on taxonomy, prevalence in CF lung infections, genomic characteristics, and adaptation strategies including modifications of metabolism and virulence, acquisition of antibiotic resistance, exchange of mobile genetic elements and development of hypermutation.
Topics: Achromobacter; Achromobacter denitrificans; Cystic Fibrosis; Gram-Negative Bacterial Infections; Humans; Lung; Prevalence
PubMed: 35931003
DOI: 10.1016/j.micres.2022.127140 -
American Journal of Infection Control Dec 2022Microbiological monitoring of disinfection of high-touch surfaces identified heavy growth of Serratia marcescens and Achromobacter xylosoxidans not present on surfaces...
BACKGROUND
Microbiological monitoring of disinfection of high-touch surfaces identified heavy growth of Serratia marcescens and Achromobacter xylosoxidans not present on surfaces before disinfection, suggesting contamination of the disinfectant used.
METHODS
An investigation included interview of the housekeeper involved, level of bacterial contamination of the in-use quaternary ammonium (Quat) disinfectant, bactericidal activity of the contaminated disinfectant, pulsed field gel electrophoresis of S.marcescens and Achromobacter isolates, survival of S. marcescens on dry surfaces, and genome sequencing to identify possible Quat resistance genes.
RESULTS
The housekeeper, who seldom cleaned patient rooms, had used the disinfectant for months without emptying and drying the bucket between uses. The contaminated disinfectant contained 9.3 × 10 CFU of S. marcescens plus A. xylosoxidans. The log reduction of S. marcescens by fresh Quat was 10-fold lower than that achieved against a control strain (S. marcescens ATCC 13380). Genome sequencing of S. marcescens isolates identified the following genes previously shown to encode for efflux pumps associated with Quat resistance: sdeXY, sdeAB, smfY, and a sugE-like gene.
CONCLUSIONS
Failure to follow existing guidelines and manufacturer's instructions for use resulted in contamination by A. xylosoxidans and by S. marcescens that possessed multiple genes associated with Quat resistance.
Topics: Humans; Disinfectants; Serratia marcescens; Disinfection; Drug Contamination; Hospitals
PubMed: 35307473
DOI: 10.1016/j.ajic.2022.03.008 -
Microbial Genomics Jul 2021spp. are emerging pathogens in patients with cystic fibrosis (CF) and spp. caused infections are associated with more severe disease outcomes and high intrinsic...
spp. are emerging pathogens in patients with cystic fibrosis (CF) and spp. caused infections are associated with more severe disease outcomes and high intrinsic antibiotic resistance. While conventional CF pathogens are studied extensively, little is known about the genetic determinants leading to antibiotic resistance and the genetic adaptation in spp. infections. Here, we analysed 101 spp. genomes from 51 patients with CF isolated during the course of up to 20 years of infection to identify within-host adaptation, mutational signatures and genetic variation associated with increased antibiotic resistance. We found that the same regulatory and inorganic ion transport genes were frequently mutated in persisting clone types within and between species, indicating convergent genetic adaptation. Genome-wide association study of six antibiotic resistance phenotypes revealed the enrichment of associated genes involved in inorganic ion transport, transcription gene enrichment in β-lactams, and energy production and translation gene enrichment in the trimethoprim/sulfonamide group. Overall, we provide insights into the pathogenomics of spp. infections in patients with CF airways. Since emerging pathogens are increasingly recognized as an important healthcare issue, our findings on evolution of antibiotic resistance and genetic adaptation can facilitate better understanding of disease progression and how mutational changes have implications for patients with CF.
Topics: Achromobacter; Adaptation, Physiological; Cystic Fibrosis; Denmark; Disease Progression; Drug Resistance, Multiple, Bacterial; Energy Metabolism; Genome, Bacterial; Genome-Wide Association Study; Gram-Negative Bacterial Infections; Host-Pathogen Interactions; Humans; Respiratory Tract Infections
PubMed: 34232117
DOI: 10.1099/mgen.0.000582 -
Antimicrobial Agents and Chemotherapy Jul 2023We conducted antimicrobial susceptibility testing of 267 isolates for 16 antibiotics from 2017 to 2022. The highest susceptibility was found for...
We conducted antimicrobial susceptibility testing of 267 isolates for 16 antibiotics from 2017 to 2022. The highest susceptibility was found for piperacillin-tazobactam (70%) and ceftazidime-avibactam (62%). Between 30% and 49% of strains were susceptible to tigecycline, ceftazidime, and meropenem. We applied species-specific Achromobacter xylosoxidans breakpoints for piperacillin-tazobactam, meropenem, and trimethoprim-sulfamethoxazole and EUCAST pharmacokinetic/pharmacodynamic (PK/PD) breakpoints for the others. A. xylosoxidans was the most frequently isolated species, followed by Achromobacter insuavis and Achromobacter ruhlandii.
Topics: Humans; Meropenem; Cystic Fibrosis; Microbial Sensitivity Tests; Anti-Bacterial Agents; Achromobacter; Piperacillin; Tazobactam
PubMed: 37310234
DOI: 10.1128/aac.00379-23 -
and activity of cefiderocol against spp. and complex, including carbapenem-non-susceptible isolates.Antimicrobial Agents and Chemotherapy Dec 2023spp. and complex (Bcc) are rare but diverse opportunistic pathogens associated with serious infections, which are often multidrug resistant. This study compared the...
spp. and complex (Bcc) are rare but diverse opportunistic pathogens associated with serious infections, which are often multidrug resistant. This study compared the antibacterial activity of the siderophore antibiotic cefiderocol against spp. and Bcc isolates with that of other approved antibacterial drugs, including ceftazidime-avibactam, ciprofloxacin, colistin, imipenem-relebactam, and meropenem-vaborbactam. Isolates were collected in the SIDERO multinational surveillance program. Among 334 spp. isolates [76.6% from respiratory tract infections (RTIs)], cefiderocol had minimum inhibitory concentration (MIC) of 0.06/0.5 µg/mL overall and 0.5/4 µg/mL against 52 (15.6%) carbapenem-non-susceptible (Carb-NS) isolates. Eleven (3.3%) spp. isolates overall and 6 (11.5%) Carb-NS isolates were not susceptible to cefiderocol. Among 425 Bcc isolates (73.4% from RTIs), cefiderocol had MIC of ≤0.03/0.5 µg/mL overall and ≤0.03/1 µg/mL against 184 (43.3%) Carb-NS isolates. Twenty-two (5.2%) Bcc isolates overall and 13 (7.1%) Carb-NS isolates were not susceptible to cefiderocol. Cumulative MIC distributions showed cefiderocol to be the most active of the agents tested against both spp. and Bcc. In a neutropenic murine lung infection model and a humanized pharmacokinetic immunocompetent rat lung infection model, cefiderocol showed significant bactericidal activity against two meropenem-resistant strains compared with untreated controls ( < 0.05) and vehicle-treated controls ( < 0.05), respectively. Meropenem, piperacillin-tazobactam, ceftazidime, and ciprofloxacin comparators showed no significant activity in these models. The results suggest that cefiderocol could be a possible treatment option for RTIs caused by spp. and Bcc.
Topics: Rats; Animals; Mice; Cefiderocol; Meropenem; Carbapenems; Cephalosporins; Burkholderia cepacia complex; Achromobacter; Drug Resistance, Multiple, Bacterial; Anti-Bacterial Agents; Ceftazidime; Respiratory Tract Infections; Ciprofloxacin; Microbial Sensitivity Tests
PubMed: 37971240
DOI: 10.1128/aac.00346-23