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Expert Review of Anti-infective Therapy 2016The HACEK group of bacteria - Haemophilus parainfluenzae, Aggregatibacter spp. (A. actinomycetemcomitans, A. aphrophilus, A. paraphrophilus, and A. segnis),... (Review)
Review
The HACEK group of bacteria - Haemophilus parainfluenzae, Aggregatibacter spp. (A. actinomycetemcomitans, A. aphrophilus, A. paraphrophilus, and A. segnis), Cardiobacterium spp. (C. hominis, C. valvarum), Eikenella corrodens, and Kingella spp. (K. kingae, K. denitrificans) - are fastidious gram-negative bacteria, part of the normal microbiota of oral and upper respiratory tract in humans. Although their pathogenicity is limited, they are responsible for 1-3% of all infective endocarditis. HACEK endocarditis mostly affect patients with underlying heart disease or prosthetic valves, and are characterized by an insidious course, with a mean diagnosis delay of 1 month (Haemophilus spp.) to 3 months (Aggregatibacter and Cardiobacterium spp.). The advent of continuously monitored blood culture systems with enriched media has erased the need for extended incubation for the diagnosis of HACEK endocarditis. Medical treatment relies on third-generation cephalosporin, with a favorable outcome in 80-90% of cases, with or without cardiac surgery.
Topics: Cephalosporins; Endocarditis, Bacterial; Gram-Negative Bacteria; Humans; Risk Factors
PubMed: 26953488
DOI: 10.1586/14787210.2016.1164032 -
BMC Infectious Diseases May 2023As a member of the HACEK group, Aggregatibacter segnis (A. segnis) is a fastidious Gram-negative coccobacillus that resides in the human oropharyngeal flora. Infective...
BACKGROUND
As a member of the HACEK group, Aggregatibacter segnis (A. segnis) is a fastidious Gram-negative coccobacillus that resides in the human oropharyngeal flora. Infective endocarditis caused by A. segnis is rarely reported.
CASE PRESENTATION
A 31-year-old male was admitted to our hospital for a 3-month history of intermittent high fever, chills, and chest distress. On presentation, he was febrile and tachycardic but otherwise with stable vital signs. Physical examination revealed systolic murmurs in the aortic and mitral valve areas. Pitting edema was evident in the lower extremities. Transthoracic echocardiography demonstrated multiple vegetations in the mitral and aortic valves. Severe regurgitation of the aortic valve and left heart dysfunction were also detected. With the suspicion of infective endocarditis and heart failure, we immediately performed microbiological tests and arranged the cardiac replacement surgery. Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry and metagenomic next-generation sequencing (mNGS) identified A. segnis from the bloodstream. While the surgical specimen culture was negative, the mNGS was positive for A. segnis. The patient was treated with ceftriaxone for four weeks and discharged. He remained clinically well, with laboratory results restored.
CONCLUSION
This is the first report of A. segnis infective endocarditis that combined MALDI-TOF and metagenomic next-generation sequencing in the diagnosis. The hypothesis-independent molecular techniques can outperform conventional tools to prevent diagnostic delay.
Topics: Male; Humans; Adult; Aggregatibacter segnis; Delayed Diagnosis; Endocarditis; Endocarditis, Bacterial; Heart Failure; Fever
PubMed: 37158846
DOI: 10.1186/s12879-023-08231-x -
Frontiers in Cellular and Infection... 2019The oral microbiota plays an important role in the human microbiome and human health, and imbalances between microbes and their hosts can lead to oral and systemic...
The oral microbiota plays an important role in the human microbiome and human health, and imbalances between microbes and their hosts can lead to oral and systemic diseases and chronic inflammation, which is usually caused by bacteria and contributes to cancer. There may be a relationship between oral bacteria and oral squamous cell carcinoma (OSCC); however, this relationship has not been thoroughly characterized. Therefore, in this study, we compared the microbiota compositions between tumor sites and opposite normal tissues in buccal mucosal of 50 patients with OSCC using the 16S rDNA sequencing. Richness and diversity of bacteria were significantly higher in tumor sites than in the control tissues. Cancer tissues were enriched in six families (, and ) and 13 genera, including and . At the species level, the abundances of , and another five species were significantly increased, suggesting a potential association between these bacteria and OSCC. Furthermore, the functional prediction revealed that genes involved in bacterial chemotaxis, flagellar assembly and lipopolysaccharide (LPS) biosynthesis which are associated with various pathological processes, were significantly increased in the OSCC group. Overall, oral bacterial profiles showed significant difference between cancer sites and normal tissue of OSCC patients, which might be onsidered diagnostic markers and treatment targets. Our study has been registered in the Chinese clinical trial registry (ChiCTR1900025253, http://www.chictr.org.cn/index.aspx).
Topics: Bacteria; Carcinoma, Squamous Cell; DNA, Ribosomal; Female; Fusobacterium nucleatum; Humans; Lipopolysaccharides; Male; Microbiota; Middle Aged; Mouth; Mouth Mucosa; Peptostreptococcus; Prevotella intermedia; RNA, Ribosomal, 16S
PubMed: 32010645
DOI: 10.3389/fcimb.2019.00476 -
International Journal of Systematic and... Sep 2006The aim of this study was to reinvestigate the relationships and the generic affiliations of the species Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus,...
Reclassification of Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus, Haemophilus paraphrophilus and Haemophilus segnis as Aggregatibacter actinomycetemcomitans gen. nov., comb. nov., Aggregatibacter aphrophilus comb. nov. and Aggregatibacter segnis comb. nov., and emended description...
The aim of this study was to reinvestigate the relationships and the generic affiliations of the species Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus, Haemophilus paraphrophilus and Haemophilus segnis. The nicotinamide phosphoribosyltransferase gene (nadV) conferring V factor-independent growth was identified in Haemophilus aphrophilus. The gene encodes a polypeptide of 462 amino acids that shows 74.5 % amino acid sequence identity to the corresponding enzyme from Actinobacillus actinomycetemcomitans. Ten isolates of Haemophilus paraphrophilus all carried a nadV pseudogene. DNA from Haemophilus aphrophilus was able to transform Haemophilus paraphrophilus into the NAD-independent phenotype. The transformants carried a full-length nadV inserted in the former locus of the pseudogene. The DNA-DNA relatedness between the type strains of Haemophilus aphrophilus and Haemophilus paraphrophilus was 77 %. We conclude that the division into two species Haemophilus aphrophilus and Haemophilus paraphrophilus is not justified and that Haemophilus paraphrophilus should be considered a later heterotypic synonym of Haemophilus aphrophilus. Forty strains of Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus and Haemophilus segnis were investigated by multilocus sequence analysis. The 40 strains form a monophyletic group clearly separate from other evolutionary lineages of the family Pasteurellaceae. We propose the transfer of Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus and Haemophilus segnis to a new genus Aggregatibacter gen. nov. as Aggregatibacter actinomycetemcomitans comb. nov. (the type species; type strain ATCC 33384(T)=CCUG 13227(T)=CIP 52.106(T)=DSM 8324(T)=NCTC 9710(T)), Aggregatibacter aphrophilus comb. nov. (type strain ATCC 33389(T)=CCUG 3715(T)=CIP 70.73(T)=NCTC 5906(T)) and Aggregatibacter segnis comb. nov. (type strain HK316(T)=ATCC 33393(T)=CCUG 10787(T)=CCUG 12838(T)=CIP 103292(T)=NCTC 10977(T)). The species of the genus Aggregatibacter are independent of X factor and variably dependent on V factor for growth in vitro.
Topics: Actinobacillus; DNA, Bacterial; Haemophilus; Molecular Sequence Data; Nicotinamide Phosphoribosyltransferase; Pentosyltransferases; RNA, Ribosomal, 16S
PubMed: 16957111
DOI: 10.1099/ijs.0.64207-0 -
Journal of Medical Microbiology Dec 2022are Gram-negative, facultatively anaerobic rods or coccobacilli that are infrequently encountered as pathogens causing infection. The range of invasive infection that...
are Gram-negative, facultatively anaerobic rods or coccobacilli that are infrequently encountered as pathogens causing infection. The range of invasive infection that cause is poorly described. The pathogenicity of species such as is debated. To identify invasive infection due to species in a large healthcare organization and to characterize clinical syndromes, co-morbidities and risk factors. All microbiological samples positive for species were identified by conventional culture or 16S rRNA PCR between October 2017 and March 2021. Electronic records for all patients with positive samples were reviewed and the infection syndrome classified for patients with invasive disease. Twenty-seven patients with invasive infection were identified, with a statistically significant difference in species-specific patterns of invasive infection (=0.02) and a statistically significant association with residence in the 30 % most deprived households in the UK by postcode (<0.01). The three most common co-morbidities were periodontitis or recent dental work (29.6%), cardiovascular disease (25.9%) and diabetes (18.5 %). We describe a novel association of with skin and soft tissue infection. The propensity of the species to cause invasive infection at different body sites and be associated with deprivation is reported. bacteraemia was associated with infective endocarditis, and was implicated in severe appendicitis and noted to cause brain abscess. Areas warranting future research include exploring the risk-factors required for invasive infection and those that may determine the species-specific differences in patterns of invasive disease.
Topics: Humans; Aggregatibacter; Retrospective Studies; RNA, Ribosomal, 16S; Endocarditis, Bacterial
PubMed: 36748613
DOI: 10.1099/jmm.0.001612 -
Clinical Microbiology Reviews Apr 2014The aim of this review is to provide a comprehensive update on the current classification and identification of Haemophilus and Aggregatibacter species with exclusive or... (Review)
Review
The aim of this review is to provide a comprehensive update on the current classification and identification of Haemophilus and Aggregatibacter species with exclusive or predominant host specificity for humans. Haemophilus influenzae and some of the other Haemophilus species are commonly encountered in the clinical microbiology laboratory and demonstrate a wide range of pathogenicity, from life-threatening invasive disease to respiratory infections to a nonpathogenic, commensal lifestyle. New species of Haemophilus have been described (Haemophilus pittmaniae and Haemophilus sputorum), and the new genus Aggregatibacter was created to accommodate some former Haemophilus and Actinobacillus species (Aggregatibacter aphrophilus, Aggregatibacter segnis, and Aggregatibacter actinomycetemcomitans). Aggregatibacter species are now a dominant etiology of infective endocarditis caused by fastidious organisms (HACEK endocarditis), and A. aphrophilus has emerged as an important cause of brain abscesses. Correct identification of Haemophilus and Aggregatibacter species based on phenotypic characterization can be challenging. It has become clear that 15 to 20% of presumptive H. influenzae isolates from the respiratory tracts of healthy individuals do not belong to this species but represent nonhemolytic variants of Haemophilus haemolyticus. Due to the limited pathogenicity of H. haemolyticus, the proportion of misidentified strains may be lower in clinical samples, but even among invasive strains, a misidentification rate of 0.5 to 2% can be found. Several methods have been investigated for differentiation of H. influenzae from its less pathogenic relatives, but a simple method for reliable discrimination is not available. With the implementation of identification by matrix-assisted laser desorption ionization-time of flight mass spectrometry, the more rarely encountered species of Haemophilus and Aggregatibacter will increasingly be identified in clinical microbiology practice. However, identification of some strains will still be problematic, necessitating DNA sequencing of multiple housekeeping gene fragments or full-length 16S rRNA genes.
Topics: Aggregatibacter; Bacteriological Techniques; Haemophilus; Haemophilus Infections; Host Specificity; Humans; Molecular Diagnostic Techniques; Pasteurellaceae Infections; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 24696434
DOI: 10.1128/CMR.00103-13 -
Rinsho Shinkeigaku = Clinical Neurology 2015A 56-year-old man who underwent a tooth extraction in the previous year presented with weakness of the right upper extremity. Brain CT and MRI scans showed subcortical...
A 56-year-old man who underwent a tooth extraction in the previous year presented with weakness of the right upper extremity. Brain CT and MRI scans showed subcortical hemorrhage in the left frontal lobe. His body temperature was 37.5°C. Blood examination revealed anemia, elevated levels of C-reactive protein, and a positive result for PR3-ANCA. Aggregatibacter segnis was identified in the incubated blood cultures, and transesophageal echocardiograms showed infectious growth in the anterior mitral leaflet. He was diagnosed with infectious endocarditis. After treatment with ceftriaxione, the clinical symptoms were improved. We concluded that infectious endocarditis caused cerebral hemorrhage and that the positive result for PR3-ANCA was a false positive. Infectious endocarditis can mimic ANCA-associated vasculitis. When ANCA-associated vasculitis is suspected, infectious endocarditis must be ruled out.
Topics: Aggregatibacter segnis; Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis; Cerebral Hemorrhage; Diagnosis, Differential; Endocarditis, Bacterial; Humans; Male; Middle Aged; Pasteurellaceae Infections
PubMed: 26041394
DOI: 10.5692/clinicalneurol.cn-000689 -
BMC Women's Health Nov 2022Gut microbes were closely related to women's health. Previous studies reported that the gut microbes of premenopausal women were different from those of postmenopausal...
BACKGROUND
Gut microbes were closely related to women's health. Previous studies reported that the gut microbes of premenopausal women were different from those of postmenopausal women. However, little was known about the relationship between gut microbiota dysbiosis and menopausal syndrome (MPS). The aim of this study was to explore the relationship between MPS and gut microbes.
METHODS
Patients with MPS (P group, n = 77) and healthy women (H group, n = 24) at menopause were recruited in this study. The stool specimen and clinical parameters (demographic data, follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), et al) of participants' were collected. We evaluated the differences in gut microbes by 16S ribosomal RNA gene sequencing. We used LEfSe to identify gut microbes with varying abundances in different groups. The Spearman correlation coefficients of clinical parameters and gut microbes were calculated. PICRUSt was used to predict the potential KEGG Ortholog functional profiles of microbial communities.
RESULTS
The abundance of 14 species differed substantially between the MPS and menopausal healthy women (LDA significance threshold > 2.0) according to LEfSe analysis. Using Spearman's correlation analysis, it was discovered that E2 had a positive correlation with Aggregatibacter segnis, Bifidobacterium animalis, Acinetobacter guillouiae (p < 0.05, these three species were enriched in menopausal healthy women), while FSH and LH had a negative correlation with them (p < 0.05). KEGG level3 metabolic pathways relevant to cardiovascular disease and carbohydrate metabolism were enriched in the MPS (p < 0.05), according to functional prediction by PICRUST and analyzed by Dunn test.
CONCLUSION
There was gut microbiota dysbiosis in MPS, which is reflected in the deficiency of the abundance of Aggregatibacter segnis, Bifidobacterium animalis and Acinetobacter guillouiae related to the level of sex hormones. In MPS individuals, species with altered abundances and unique functional pathways were found.
Topics: Humans; Female; Dysbiosis; Gastrointestinal Microbiome; Luteinizing Hormone; Follicle Stimulating Hormone; Menopause
PubMed: 36348390
DOI: 10.1186/s12905-022-02029-w -
BMC Microbiology Sep 2022Tongue coating is an important health indicator in traditional Chinese medicine (TCM). The tongue coating microbiome can distinguish disease patients from healthy...
BACKGROUND
Tongue coating is an important health indicator in traditional Chinese medicine (TCM). The tongue coating microbiome can distinguish disease patients from healthy controls. To study the relationship between different types of tongue coatings and health, we analyzed the species composition of different types of tongue coatings and the co-occurrence relationships between microorganisms in Chinese adults. From June 2019 to October 2020, 158 adults from Hangzhou and Shaoxing City, Zhejiang Province, were enrolled. We classified the TCM tongue coatings into four different types: thin white tongue fur (TWF), thin yellow tongue fur (TYF), white greasy tongue fur (WGF), and yellow greasy tongue fur (YGF). Tongue coating specimens were collected and used for 16S rRNA gene sequencing using the Illumina MiSeq system. Wilcoxon rank-sum and permutational multivariate analysis of variance tests were used to analyze the data. The microbial networks in the four types of tongue coatings were inferred independently using sparse inverse covariance estimation for ecological association inference.
RESULTS
The microbial composition was similar among the different tongue coatings; however, the abundance of microorganisms differed. TWF had a higher abundance of Fusobacterium periodonticum and Neisseria mucosa, the highest α-diversity, and a highly connected community (average degree = 3.59, average closeness centrality = 0.33). TYF had the lowest α-diversity, but the most species in the co-occurrence network diagram (number of nodes = 88). The platelet-to-lymphocyte ratio (PLR) was associated with tongue coating (P = 0.035), and the YGF and TYF groups had higher PLR values. In the co-occurrence network, Aggregatibacter segnis was the "driver species" of the TWF and TYF groups and correlated with C-reactive protein (P < 0.05). Streptococcus anginosus was the "driver species" in the YGF and TWF groups and was positively correlated with body mass index and weight (P < 0.05).
CONCLUSION
Different tongue coatings have similar microbial compositions but different abundances of certain bacteria. The co-occurrence of microorganisms in the different tongue coatings also varies. The significance of different tongue coatings in TCM theory is consistent with the characteristics and roles of the corresponding tongue-coating microbes. This further supports considering tongue coating as a risk factor for disease.
Topics: Adult; Bacteria; Humans; Medicine, Chinese Traditional; Microbiota; RNA, Ribosomal, 16S; Tongue
PubMed: 36085010
DOI: 10.1186/s12866-022-02626-7 -
BMC Infectious Diseases May 2022The bacterial genus Aggregatibacter was categorized in 2006 to accommodate the former Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus, and H. segnis...
BACKGROUND
The bacterial genus Aggregatibacter was categorized in 2006 to accommodate the former Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus, and H. segnis species. Aggregatibacter kilianii is a normal resident of the human upper respiratory tract but can also cause serious infections. A. kilianii is relatively newly identified and has been isolated from conjunctivitis, wounds, abdominal abscesses, and blood.
CASE PRESENTATION
An 80-year-old female patient with distal common bile duct cancer was admitted to our hospital with sudden loss of consciousness and general weakness, fever, and abdominal pain for 3 days. Two colonial morphologies were isolated from both the blood and bile cultures; one was identified as Streptococcus constellatus subsp. pharyngis, but the other was not recognized by Vitek2 and MALDI-TOF. The 16 S rRNA sequences showed 99.73% similarity with the sequence of A. kilianii strains.
CONCLUSION AND DISCUSSION
This article presents the first case of a clinical isolate of A. kilianii outside Europe. This case is also the first of the antimicrobial profile of this strain. This report highlights the importance of proper molecular identification for timely diagnosis and treatment of disease.
Topics: Aged, 80 and over; Aggregatibacter; Aggregatibacter aphrophilus; Female; Humans; Streptococcus
PubMed: 35619055
DOI: 10.1186/s12879-022-07471-7