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Journal of Microbiology, Immunology,... Aug 2020Lemierre's syndrome, also known as post-anginal septicemia or necrobacillosis, is characterized by bacteremia, internal jugular vein thrombophlebitis, and metastatic... (Review)
Review
Lemierre's syndrome, also known as post-anginal septicemia or necrobacillosis, is characterized by bacteremia, internal jugular vein thrombophlebitis, and metastatic septic emboli secondary to acute pharyngeal infections. Modern physicians have "forgotten" this disease. The most common causative agent of Lemierre's syndrome is Fusobacterium necrophorum, followed by Fusobacterium nucleatum and anaerobic bacteria such as streptococci, staphylococci, and Klebsiella pneumoniae. The causative focus mostly originated from pharyngitis or tonsillitis, accounting for over 85% of the cases of Lemierre's syndrome. Pneumonia or pleural empyema is the most common metastatic infection in Lemierre's syndrome. Antimicrobial therapy should be prescribed for 3-6 weeks. The treatment regimens include metronidazole and β-lactam antibiotics. In recent years, the antibiotic stewardship program has resulted in decreased antibiotic prescription for upper respiratory tract infections. The incidence of Lemierre's syndrome has increased over the past decade. F. necrophorum is an underestimated cause of acute pharyngitis or tonsillitis. A high index of suspicion is required for the differential diagnosis of acute tonsillopharyngitis with persistent neck pain and septic syndrome.
Topics: Anti-Bacterial Agents; Bacteria; Bacteria, Anaerobic; Communicable Diseases, Emerging; Fusobacterium necrophorum; Humans; Lemierre Syndrome; Pharyngitis; Sepsis
PubMed: 32303484
DOI: 10.1016/j.jmii.2020.03.027 -
Cancer Medicine Sep 2020Bacteria identified in the oral cavity are highly complicated. They include approximately 1000 species with a diverse variety of commensal microbes that play crucial... (Review)
Review
Bacteria identified in the oral cavity are highly complicated. They include approximately 1000 species with a diverse variety of commensal microbes that play crucial roles in the health status of individuals. Epidemiological studies related to molecular pathology have revealed that there is a close relationship between oral microbiota and tumor occurrence. Oral microbiota has attracted considerable attention for its role in in-situ or distant tumor progression. Anaerobic oral bacteria with potential pathogenic abilities, especially Fusobacterium nucleatum and Porphyromonas gingivalis, are well studied and have close relationships with various types of carcinomas. Some aerobic bacteria such as Parvimonas are also linked to tumorigenesis. Moreover, human papillomavirus, oral fungi, and parasites are closely associated with oropharyngeal carcinoma. Microbial dysbiosis, colonization, and translocation of oral microbiota are necessary for implementation of carcinogenic functions. Various underlying mechanisms of oral microbiota-induced carcinogenesis have been reported including excessive inflammatory reaction, immunosuppression of host, promotion of malignant transformation, antiapoptotic activity, and secretion of carcinogens. In this review, we have systemically described the impact of oral microbial abnormalities on carcinogenesis and the future directions in this field for bringing in new ideas for effective prevention of tumors.
Topics: Alphapapillomavirus; Bacteria, Aerobic; Bacteria, Anaerobic; Bacterial Translocation; Cell Transformation, Neoplastic; Disease Progression; Dysbiosis; Firmicutes; Fungi; Fusobacterium nucleatum; Humans; Immune Tolerance; Microbiota; Mouth; Neoplasms; Oropharyngeal Neoplasms; Porphyromonas gingivalis
PubMed: 32638533
DOI: 10.1002/cam4.3206 -
The Journal of Biological Chemistry Mar 2020An early exposure to lipid biochemistry in the laboratory of Konrad Bloch resulted in a fascination with the biosynthesis, structures, and functions of bacterial lipids....
An early exposure to lipid biochemistry in the laboratory of Konrad Bloch resulted in a fascination with the biosynthesis, structures, and functions of bacterial lipids. The discovery of plasmalogens (1-alk-1'-enyl, 2-acyl phospholipids) in anaerobic Gram-positive bacteria led to studies on the physical chemistry of these lipids and the cellular regulation of membrane lipid polymorphism in bacteria. Later studies in several laboratories showed that the formation of the alk-1-enyl ether bond involves an aerobic process in animal cells and thus is fundamentally different from that in anaerobic organisms. Our work provides evidence for an anaerobic process in which plasmalogens are formed from their corresponding diacyl lipids. Studies on the roles of phospholipases in revealed distinctions between its phospholipases and those previously discovered in other bacteria and showed how the enzymes are uniquely fitted to the intracellular lifestyle of this significant human pathogen.
Topics: Anaerobiosis; Bacteria, Anaerobic; Fatty Acids; Gram-Positive Bacteria; Lipids; Phosphatidylethanolamines; Plasmalogens
PubMed: 32221031
DOI: 10.1074/jbc.X120.013022 -
International Journal of Infectious... Jan 2021For decades, the term "anti-anaerobic" has been commonly used to refer to antibiotics exhibiting activity against anaerobic bacteria, also designated as anaerobes. This... (Review)
Review
For decades, the term "anti-anaerobic" has been commonly used to refer to antibiotics exhibiting activity against anaerobic bacteria, also designated as anaerobes. This term is used in various situations ranging from infections associated with well-identified pathogens like Clostridioides difficile, or Fusobacterium necrophorum in Lemierre's syndrome, that require specific antibiotic treatments to polymicrobial infections generally resulting from the decreased permeability of anatomical barriers (e.g., intestinal translocation and stercoral peritonitis) or infectious secondary localizations (e.g., brain abscess and infectious pleurisy). In these cases, the causal bacteria generally remain unidentified and the antimicrobial treatment is empirical. However, major progress in the knowledge of human bacterial microbiotas in the last 10 years has shown how diverse are the species involved in these communities. Here, we sought to reappraise the concept of anti-anaerobic spectrum in the light of recent advances in the microbiota field. We first highlight that the term anaerobic itself does not represent the tremendous diversity of the bacteria it spans, and then we stress that the antibiotic susceptibility profiles for most anaerobic bacteria remain unaddressed. Furthermore, we provide examples challenging the relevance of the "anti-anaerobic" spectrum from a clinical and ecological perspective.
Topics: Anaerobiosis; Animals; Anti-Bacterial Agents; Bacteria, Anaerobic; Humans; Microbiota; Terminology as Topic
PubMed: 33127500
DOI: 10.1016/j.ijid.2020.10.052 -
Anaerobe Oct 2021This was a multicenter, retrospective study of patients with anaerobic bacteremia comparing metronidazole 500 mg every 8 h versus 500 mg every 12 h. Of 782 patients...
This was a multicenter, retrospective study of patients with anaerobic bacteremia comparing metronidazole 500 mg every 8 h versus 500 mg every 12 h. Of 782 patients reviewed, 85 met inclusion criteria. There was no significant difference in mortality, length of stay, or escalation of therapy between dosing strategies.
Topics: Aged; Anti-Bacterial Agents; Bacteremia; Bacteria, Anaerobic; Drug Administration Schedule; Female; Humans; Length of Stay; Male; Metronidazole; Middle Aged; Retrospective Studies; Treatment Outcome
PubMed: 33965559
DOI: 10.1016/j.anaerobe.2021.102378 -
Anaerobe Apr 2021
Topics: Animals; Bacteria, Anaerobic; Humans; Microbiota
PubMed: 33975719
DOI: 10.1016/j.anaerobe.2021.102362 -
Current Opinion in Infectious Diseases Dec 2019Anaerobic bacteria are implicated in a broad range of infections and can cause significant morbidity and mortality. As such, development of antimicrobial resistance... (Review)
Review
PURPOSE OF REVIEW
Anaerobic bacteria are implicated in a broad range of infections and can cause significant morbidity and mortality. As such, development of antimicrobial resistance (AMR) increases the risk of worse clinical outcomes and death.
RECENT FINDINGS
Anaerobe AMR is highly variable according to region and species included in the survey. The overall trend is to increasing resistance, particularly in Europe and Asia, and in the Bacteroides fragilis group and Clostridium sp. Conversely, with the decline in RT027, resistance in Clostridiodes difficile is decreasing. Resistance to moxifloxacin and clindamycin has reached 30-50%, whereas prevalence of metronidazole and carbapenem resistance is generally low. Infections due to multidrug anaerobes have been increasingly reported, with clinical studies demonstrating adverse clinical outcomes, including higher mortality, with anaerobic resistance or inappropriate therapy. The role of antimicrobial stewardship in the setting of increasing anaerobe resistance is yet to be fully elucidated.
SUMMARY
These findings highlight the importance of continuous surveillance in monitoring emerging trends in anaerobe AMR. Mean inhibitory concentrations should be reported due to variable susceptibility breakpoints and for detection of isolates with reduced susceptibility. At a local level, the clinical microbiology laboratory has a key role in identifying and undertaking susceptibility testing to inform individual patient management, develop local antibiograms and liaise with antimicrobial stewardship teams. A greater understanding of the clinical impact of anaerobic resistance and the role of antimicrobial stewardship in preventing resistance is required.
Topics: Anti-Bacterial Agents; Antimicrobial Stewardship; Bacteria, Anaerobic; Bacterial Infections; Drug Resistance, Bacterial; Drug Resistance, Multiple, Bacterial; Health Care Surveys; Humans
PubMed: 31567734
DOI: 10.1097/QCO.0000000000000595 -
Future Microbiology Aug 2019Multidrug resistance (MDR) in anaerobes is not a well-known topic. group isolates have numerous resistance determinants such as multidrug efflux pumps, and genes and... (Review)
Review
Multidrug resistance (MDR) in anaerobes is not a well-known topic. group isolates have numerous resistance determinants such as multidrug efflux pumps, and genes and activating insertion sequences, and some isolates exhibited extensive drug-resistant patterns. MDR rates in group were from 1.5 to >18% and up to >71% in and positive isolates carrying insertion sequences. MDR was present in >1/2 of isolates, most often in epidemic/hypervirulent strains and unusually high metronidazole or vancomycin resistance has been reported in single studies. MDR was found in spp. (in ≤10% of isolates), spp. and . Resistance in the anaerobes tends to be less predictable and anaerobic microbiology is required in more laboratories. New hopes may be new antibiotics such as eravacycline, cadazolid, surotomycin, ridinilazol or toxoid vaccines; however, more efforts are needed to track the MDR in anaerobes.
Topics: Anti-Bacterial Agents; Bacteria, Anaerobic; Bacterial Infections; Drug Resistance, Multiple, Bacterial; Genes, Bacterial; Humans; Prevalence
PubMed: 31469008
DOI: 10.2217/fmb-2019-0132 -
Anaerobe Jun 2022To date, antimicrobial susceptibility testing (AST) in anaerobes is highly disarrayed. The testing is not routinely performed in many laboratories to direct appropriate... (Review)
Review
To date, antimicrobial susceptibility testing (AST) in anaerobes is highly disarrayed. The testing is not routinely performed in many laboratories to direct appropriate antimicrobial therapy, and literature on AST remains scarce. This review aims to present the current methods employed for the AST of anaerobic bacteria both in routine and research. Anaerobes are potential human pathogens and predominate the human microbiota. Despite their significant role in human health and disease, they are not paid enough heed. The educated experience-based treatment has often been instituted with anaerobic infections due to the challenging AST and relatively predictable patterns of antimicrobial resistance (AMR). However, the AMR in anaerobes remains no more predictable, especially in Gram-negative anaerobes like Bacteroides spp., where multi-drug resistance is also emerging. The changing antibiograms and the emergence of resistance determinants in anaerobes necessitate routine AST, periodic monitoring, and literature review of these organisms. The present scenario dictates to limit the empirical management of anaerobic infections and encourage consistent AST practice in routine by employing economical, faster, and more pragmatic approaches, especially in tertiary care setups that cater to a vast patient population and are held accountable for producing accurate clinical and surveillance data. The article may provide a broad perspective on the topic and different AST solutions.
Topics: Anti-Bacterial Agents; Anti-Infective Agents; Bacteria, Anaerobic; Bacterial Infections; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests
PubMed: 35417767
DOI: 10.1016/j.anaerobe.2022.102559 -
Current Opinion in Chemical Biology Aug 2019Fluorescence microscopy is a powerful tool for investigating living cells. While widely used fluorescent proteins, such as green fluorescent protein (GFP), have had huge... (Review)
Review
Fluorescence microscopy is a powerful tool for investigating living cells. While widely used fluorescent proteins, such as green fluorescent protein (GFP), have had huge impact in biological imaging because they provide genetically encoded, highly specific labeling, these probes require oxygen to generate fluorescence. This crucial oxidative step has limited the use of GFP-like proteins in anaerobic bacterial systems and restricted live-cell studies of obligate anaerobes and their biology. This review discusses alternative approaches to labeling proteins in anaerobic bacteria that are compatible with live-cell fluorescence microscopy in strict oxygen-free environments. The advantages, disadvantages, and likelihood of successful implementation for each approach are considered to provide context and guide further advances in anaerobic fluorescence labeling.
Topics: Anaerobiosis; Bacteria, Anaerobic; Bacterial Proteins; Fluorescent Dyes; Green Fluorescent Proteins; Microscopy, Fluorescence
PubMed: 31252372
DOI: 10.1016/j.cbpa.2019.05.008