Empyema caused by Eikenella halliae diagnosed by metagenomic next-generation sequencing (mNGS) after pulmonary surgery: A case report.

Background: Empyema is one of the complications of pulmonary surgery for lung cancer, the incidence of which is not very high, but in severe cases, it can even lead to death, and it is always difficult to diagnose the cause by conventional methods. Case presentation: In this study, we report a clinical case of empyema caused by Eikenella halliae after pulmonary surgery in a 55-year-old man. He had a fever, cough, and expectoration for 3 days and was diagnosed with right hydropneumothorax and empyema, pneumonia, postoperative malignant tumor of the right lower lobe (adenocarcinoma), and hypertension. The microbiology laboratory reported Gram-negative bacteria in pleural effusion, which was preliminarily considered as Eikenella based on culture and 16S rRNA sequencing. Furthermore, metagenomic next-generation sequencing (mNGS) of sputum samples was performed two times and reported negative results and the presence of E. halliae, respectively. The pathogen was finally confirmed as E. halliae by whole genome sequencing, suggesting the high-resolution ability of mNGS in the clinical diagnosis of this case. Conclusion: To our knowledge, this is the first case report of E. halliae infection in China, indicating increased pathogenicity of Eikenella sp. in immunocompromised patients, especially after invasive operations. Our findings emphasize that mNGS allows bacterial diagnosis of empyema and can significantly improve the accuracy of the diagnosis.

Eikenella glucosivorans sp. nov., isolated from a human throat swab, and emendation of the genus Eikenella to include saccharolytic species.

A novel species within the genus Eikenella is described, based on the phenotypical, biochemical and genetic characterization of a strain of a facultatively anaerobic, Gram-negative rod-shaped bacterium. Strain S3360T was isolated from the throat swab of a patient sampled during routine care at a hospital. Phylogenetic analyses (full-length 16S rRNA gene and whole-genome sequences) placed the strain in the genus Eikenella, separate from all recognized species but with the closest relationship to Eikenella longinqua (NML 02-A-017T). Eikenella is one of the genera in the HACEK group known to be responsible for rare cases of endocarditis in humans. Until the recent descriptions of Eikenella exigua, Eikenella halliae and Eikenella longinqua, Eikenella corrodens had been the only validly published species in this genus since its description as Bacteroides corrodens in 1958. Unlike these species, strain S3360T is able to metabolize carbohydrates (glucose). The average nucleotide identities of strain S3360T with E. longinqua (NML 02-A-017T) and E. corrodens (NCTC 10596T), the type species of the genus, were 90.5 and 84.7 %, respectively, and the corresponding genome-to-genome distance values were 41.3 and 29.0 %, respectively. The DNA G+C content of strain S3360T was 58.4 mol%. Based on the phenotypical, biochemical and genetic findings, strain S3360T is considered to represent a novel species within the genus Eikenella, for which the name Eikenella glucosivorans sp. nov. is proposed. The type strain is S3360T (DSM 110714T=CCOS 1935T=CCUG 74293T). In addition, an emendation of the genus Eikenella is proposed to include species which are saccharolytic.

Description of Eikenella halliae sp. nov. and Eikenella longinqua sp. nov., derived from human clinical materials, emendation of Eikenella exigua Stormo et al. 2019 and emendation of the genus Eikenella to include species which are strict anaerobes.

The Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, Kingella (HACEK) group genus Eikenella contained a single species, Eikenella corrodens, for many years. In November 2019, Eikenella exigua was described after recovery from a brain abscess and blood culture in Norway. Coincidentally, characterization of 22 Gram-negative bacteria resembling Eikenella from 17 Canadian patients had been underway. Seven isolates from five patients were conclusively identifiable as E. corrodens. One (NML 120819) was deemed to represent a species of the genus Eikenella most closely related to E. corrodens. Fourteen isolates had 97.6 to 98.8% similarities to E. corrodens by 16S rRNA gene sequencing, forming three distinct groups by genome analyses. The largest contained ten anaerobic isolates from eight patients recovered from blood, brain, bone and other abscesses; upon re-evaluation, this group was found to be most consistent with E. exigua. A second facultatively anaerobic clade consisted of two ocular isolates from one patient and a sinus isolate from a second patient. The third taxon consisted of a single strictly anaerobic blood culture isolate. The novel taxa, like E. corrodens, were poorly reactive biochemically and difficult to discern from each other phenotypically and chemotaxonomically, including by cellular fatty acids. MALDI-TOF (Bruker) and whole-genome sequencing were used to further characterize isolates. Draft genomes for the strains had similar DNA G+C contents (55.38-58.53 mol%) while sizes varied from 1.82 Mb to 2.54 Mb. We propose here emendations of the genus Eikenella and the species Eikenella exigua, as well as describing Eikenella halliae sp. nov. NML 130454T (=LMG 30894T=NCTC 14180T) and Eikenella longinqua sp. nov. NML 02-A-017T (=LMG 30896T=NCTC 14179T), on the basis of these findings.

How best to approach these acute hand infections.

Antimicrobial therapy is not straightforward with the 4 infectious conditions reviewed here. Combination therapy at the start must usually be tailored once an organism is known.

Eikenella exigua sp. nov., isolated from brain abscess and blood.

We herein describe the first novel species within the genus Eikenella since it was established in 1972 by the reclassification of 'Bacteroides corrodens' to Eikenella corrodens. From a polymicrobial brain abscess, we encountered an Eikenella isolate, PXXT, that could not validly be named E. corrodens. The isolate grew on blood agar with small, translucent, pitting colonies after 3 days of anaerobic incubation. By reviewing previously collected invasive isolates, we found an additional Eikenella strain, EI-02, from a blood culture exhibiting the same properties as PXXT. Phylogenetic analyses based on both whole genome and individual house-keeping genes confirmed that the two strains allocate in a phylogenetic cluster separate from E. corrodens. Using specific amplification and sequencing of the Eikenella nusG gene, we further detected the novel Eikenella species in six historic brain abscesses previously reported to contain E. corrodens based on 16S metagenomics. Out of 24 Eikenella whole-genome projects available in GenBank, eight cluster together with PXXT and EI-02. These isolates were recovered from brain abscess (n=2), blood (n=1), bone/soft tissue (n=3), parotid gland (n=1) and unknown (n=1). It remains to be investigated whether the new species can cause endocarditis. The average nucleotide identity value between strain PXXT and the E. corrodens type strain ATCC 23834T was 92.1 % and the corresponding genome-to-genome distance value was 47.1 %, both supporting the classification of PXXT as a novel species. For this species we propose the name Eikenella exigua. The type strain of E. exigua is PXXT (DSM 109756T, NCTC 14318T).

Salivary calculi microbiota: new insights into microbial networks and pathogens reservoir.

Sialolithiasis represents the most common disorders of salivary glands in middle-aged patients. It has been hypothesized that the retrograde migration of bacteria from the oral cavity to gland ducts may facilitate the formation of stones. Thus, in the present study, a microbiome characterization of salivary calculi was performed to evaluate the abundance and the potential correlations between microorganisms constituting the salivary calculi microbiota. Our data supported the presence of a core microbiota of sialoliths constituted principally by Streptococcus spp., Fusobacterium spp. and Eikenella spp., along with the presence of important pathogens commonly involved in infective sialoadenitis.

Epidural Abscess Caused by Eikenella corrodens in a Previously Healthy Child

Eikenella corrodens rarely causes invasive head and neck infections in immunocompetent children. We report a case of epidural abscess caused by E. corrodens in a previously healthy 13-year-old boy who presented with fever, headache, and vomiting. On physical examination upon admission, there was no neck stiffness, but discharge from the right ear was observed. Brain magnetic resonance imaging (MRI) revealed approximately 4.5-cm-sized epidural empyema on the right temporal lobe as well as bilateral ethmoid and sphenoid sinusitis, right mastoiditis, and right otitis media. During treatment with vancomycin and cefotaxime, purulent ear discharge aggravated, and on follow-up brain MRI, the empyema size increased to 5.6×3.4 cm with interval development of an abscess at the right sphenoid sinus. Burr hole trephination was performed, and foul-smelling pus was aspirated from the epidural abscess near the right temporal lobe. Pus culture yielded E. corrodens. Endoscopic sphenoidotomy was also performed with massive pus drainage, and the same organism was grown. The patient was treated with intravenous cefotaxime for 3 weeks and recovered well with no other complications. Therefore, E. corrodens can cause serious complications in children with untreated sinusitis.

Bacilos gramnegativos de crecimiento lento: grupo HACEK, Capnocytophaga y Pasteurella / Fastidious gram-negative rods: HACEK group, Capnocytophaga and Pasteurella

Las bacterias del grupo HACEK (Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, Kingella), Pasteurella y Capnocytophaga son las bacterias gramnegativas de crecimiento lento que con mayor frecuencia causan infecciones en el ser humano. Forman parte de la microbiota del tracto respiratorio superior y genitourinario del ser humano y de animales, y pueden causar infecciones en cualquier localización, pero fundamentalmente de piel y tejidos blandos, así como bacteriemia y endocarditis. Su clasificación taxonó- mica es compleja y está en constante revisión. Son bacterias nutricionalmente exigentes, y para el desarrollo de colonias visibles requieren agar sangre y agar chocolate, una atmósfera aerobia, generalmente enriquecida en CO2 y una incubación de 48 h. La identificación fenotípica de especie es complicada y no siempre es posible, ya que requiere múltiples sustratos que normalmente no están disponibles en los laboratorios de rutina, ni en los sistemas automatizados. La aplicación de las técnicas moleculares y proteómicas ha permitido una mejor identificación de estas bacterias. El tratamiento de estas infecciones se encuentra con el problema de que los datos de sensibilidad a los agentes antimicrobianos son limitados; no obstante, de los datos disponibles se conoce que amoxicilina-ácido clavulánico, cefalosporinas de segunda y tercera generaciones y fluoroquinolonas son generalmente activas frente a ellas (AU)

Bacteria from the HACEK group (Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, Kingella), Pasteurella and Capnocytophaga are slow-growing gram-negative bacteria that most frequently cause infections in humans. They are part of the microbiota of the upper respiratory and genitourinary tracts of humans and animals, and can cause infections in any location, although mainly skin and soft tissue infections, as well as bacteraemia and endocarditis. Taxonomic classification is complex and under constant review. These are nutritionally demanding bacteria that require blood and chocolate agar, an aerobic atmosphere, generally CO2-enriched, and 48 h incubation for the development of visible colonies. Phenotypic identification at the species level is complicated and not always possible because it requires multiple substrates that are not normally available in routine laboratories or in automated systems. Application of molecular and proteomic techniques has enabled better identification of these bacteria. Treatment of related infections is hindered by a lack of data on susceptibility to antimicrobial agents. However, evidence suggests that amoxicillin-clavulanic acid, second- and third-generation cephalosporins and fluoroquinolones are generally active against these bacteria (AU)

Purificación y caracterización de lipopolisacáridos de Eikenella corrodens 23834 y Porphyromonas gingivalis W83 / Purification and characterization of lipopolysaccharide from Eikenella corrodens 23834 and Porphyromonas gingivalis W83

La purificación de lipopolisacáridos (LPS) o endotoxinas y su caracterización es un aspecto esencial para estudios que buscan aclarar el papel de estas biomoléculas de bacterias Gram negativas presentes en la cavidad oral y su relación con enfermedades locales periodontales y sistémicas. Este estudio implementa una metodología para la extracción, purificación y caracterización de LPS a partir de bacteria completa de Eikenella corrodens 23834 y Porphyromonas gingivalis W83, utilizando técnicas previamente descritas. La extracción cruda de LPS se realizó con fenol-agua caliente; la purificación se realizó con tratamiento enzimático con nucleasas y proteasa, seguido de cromatografía de exclusión por tamaño (Sephacryl S-200 HR) con deoxicolato de sodio como fase móvil. La caracterización de los extractos purificados se realizó por barrido espectrofotométrico, pruebas bioquímicas de electroforesis SDS-PAGE, ensayo Purpald y la prueba cromogénica de LAL. Como control para la identificación y caracterización de los extractos purificados se utilizaron LPS comerciales de Escherichia coli, Salmonella typhimurium, Rodobacter sphaeroides y Porphyromonas gingivalis. La metodología implementada permitió la obtención de LPS de elevada pureza con la identificación de KDO o heptosas, un quimiotipo de LPS-S (liso) para E. corrodens y LPS-SR (semi-rugoso) para P. gingivalis W83. Ambos LPS purificados mostraron capacidad endotóxica a bajas concentraciones. La metodología implementada en este estudio para la purificación y caracterización de LPS a partir de bacteria completa fue eficiente al compararla con los LPS comerciales.

Purification of lipopolysaccharide (LPS) or endotoxins and its characterization is an important aspect for studies aimed at clarify the role of these biomolecules from Gram negative bacteria present in the oral cavity and its relationship with periodontal and systemic diseases. This study describes an extraction, purification and characterization method of LPS from Eikenella corrodens 23834 and Porphyromonas gingivalis W83. LPS extraction was performed by using hot phenol-water; the purification was done with nuclease and protease enzymatic treatment, followed by size-exclusion chromatography (Sephacryl S-200 HR) with sodium deoxycholate as mobile phase. The characterization of the purified extracts was performed by spectrophotometric scanning, SDS-PAGE biochemical tests, Purpald assay and chromogenic LAL test. As control, commercial LPS from Escherichia coli, Salmonella typhimurium, P. gingivalis, and Rodobacter sphaeroides were used. The methodology mentioned above had allowed obtaining high purity LPS by identifying KDO or heptoses, a chemotype S-LPS (smooth) to E. corrodens; SR-LPS (semi-rough) for P. gingivalis W83. Both purified LPS showed endotoxic capacity at low concentrations. The methodology used in this study for purification and characterization of LPS from the whole bacteria was efficient when it was compared with commercial LPS.

Subgingival biodiversity in subjects with uncontrolled type-2 diabetes and chronic periodontitis.

BACKGROUND AND OBJECTIVE: There is a bidirectional relationship between periodontal disease and type-2 diabetes mellitus (DM). Inflammatory mediators may negatively affect glycemic control, and increased glucose levels and resultant glycation end-products may alter the host response against bacterial infection. However, no agreement has been reached regarding the effect of DM on periodontal subgingival microbiota. Therefore, the purpose of the present study was to compare the subgingival biodiversity in deep periodontal pockets of subjects with chronic periodontitis and either uncontrolled type-2 diabetes or no diabetes using 16S rRNA gene cloning and sequencing. MATERIAL AND METHODS: Twelve subjects with uncontrolled type-2 diabetes (glycated hemoglobin > 8%) and eleven nondiabetic subjects presenting severe and generalized chronic periodontitis were selected. Subgingival biofilm from periodontal pockets > 5 mm were assessed using the 16S rRNA gene cloning and sequencing technique. RESULTS: Significant differences were observed in subgingival microbiota between diabetic and nondiabetic subjects. Diabetic subjects presented higher percentages of total clones of TM7, Aggregatibacter, Neisseria, Gemella, Eikenella, Selenomonas, Actinomyces, Capnocytophaga, Fusobacterium, Veillonella and Streptococcus genera, and lower percentages of Porphyromonas, Filifactor, Eubacterium, Synergistetes, Tannerella and Treponema genera than nondiabetic individuals (p < 0.05). Moreover, some phylotypes, such as Fusobacterium nucleatum, Veillonella parvula, V. dispar and Eikenella corrodens were detected significantly more often in diabetic subjects than in nondiabetic subjects (p < 0.05). CONCLUSION: Subjects with uncontrolled type-2 diabetes and chronic periodontitis presented significant dissimilarities in subgingival biodiversity compared with nondiabetic subjects.

Cervical necrotizing fasciitis originating with a periapical infection.

BACKGROUND: Necrotizing fasciitis is a rapidly spreading, soft-tissue infection involving the subcutaneous tissues. Necrotizing fasciitis originating from a dental-related source is rare. Practitioners should be aware that this infection could occur in patients who are immunocompromised and in patients who are healthy. Practitioners must treat this disease aggressively with surgical debridement and intensive medical support. CASE DESCRIPTION: The authors present a case report of a man with poorly controlled diabetes mellitus in whom a periapical infection progressed into a maxillofacial space abscess and finally cervical necrotizing fasciitis (CNF). A delay in his initial visit to a dentist was evident. The authors observed a successful outcome in the patient after he underwent several wide surgical debridement procedures, hyperbaric oxygen therapy and a protracted, intensive hospital stay lasting 34 days. CONCLUSIONS: Dentists should suspect that a patient has CNF when maxillofacial cellulitis or an abscess does not respond to conventional therapy. Findings of spreading skin erythema, induration, purple discoloration and anesthesia suggest necrotizing fasciitis. Early computed tomography scans may reveal gas within the deep tissues of the neck, fascial plane involvement or both. CLINICAL IMPLICATIONS: CNF has high morbidity and mortality rates if rapid aggressive therapy is not pursued. Spread of this polymicrobial infection can lead to mediastinitis or cranial base involvement. Mortality is directly proportional to the time to intervention.

Meningitis and epidural abscess related to pansinusitis.

Sinusitis can rarely be latent and present directly with intracranial complications. We present the case of an 11-year-old girl who presented with typical features of meningitis. She underwent neuroimaging because of slow improvement and concern for a brain abscess. Despite no history or examination findings suggestive of sinusitis, she was found to have pansinusitis with intracranial extension causing meningitis and epidural abscess.

A Case of Haemophilus parainfluenzae Endocarditis / 대한임상미생물학회지

The HACEK group of bacteria (Haemophilus parainfluenzae, H. aphrophilus, H. paraphrophilus, Actinobacilus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corodens, and Kingella kingae) are the normal flora of the upper respiratory tract and oropharynx. The organisms infect abnormal cardiac valves, causing subacute native endocarditis or prosthetic valve endocarditis more than one year after valve surgery. Haemophilus species are responsible for only 0.5~1% of all infective endocarditis cases. Embolization occurs in 60% and the mortality rate ranges from 16~45% of cases of infective endocarditis caused by H. parainfluenzae. We experienced a case of infective endocarditis due to H. parainfluenzae in a 37-year-old male admitted with high fever, chills, nausea & vomiting, chest discomfort, and blurred vision. The organism was isolated from a blood culture and was identified as H. parainfluenzae by factor V requirement, negativity at urea, positivity at ornithine decarboxylase, and acid production from glucose and maltose. The patient was treated with antibiotics and symptoms and signs were improved

Utility of extended blood culture incubation for isolation of Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, and Kingella organisms: a retrospective multicenter evaluation.

The incidence of and average time to detection for Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, and Kingella (HACEK) bacteria in blood cultures with standard incubation and the utility of extended incubation of blood culture bottles were reviewed at four tertiary care microbiology laboratories. HACEK organisms were isolated from 35 (<0.005%) of 59,203 positive blood cultures. None of 407 blood cultures with extended incubation grew HACEK or other bacteria. Bacteremia from HACEK bacteria is rare, and extended incubation of blood cultures to recover HACEK bacteria is unnecessary.

A Case of Liver Abscess due to Eikenella corrodens Caused by Human Bites / 감염과화학요법

Eikenella corrodens is a slow growing, facultatively anaerobic gram-negative rod that is part of the normal flora of the oral cavity and upper respiratory tracts. In most patients with E. corrodens infections, host defenses are compromised due to surgery, or chronic debilitating illness such as malignancies, or immunosuppressive therapy. This organism causes abscesses and infections that are at times fatal. We experienced a case of E. corrodens isolated from liver abscess in an immunocompetent patient. A 50-year-old man who is a dentist, was hospitalized because of fever and myalgia of 10 days' duration. Abdominal ultrasonography showed non-septated, 3.8x4.6 cm sized abscess in the segment 6/7 of the liver. E. corrodens was isolated from aspiration of liver abscess. This organism was presumably acquired from his patient's oral cavity during dental procedure. We hope that increased awareness to E. corrodens will raise the index of suspicion, and contribute to optimal management of these infections, minimizing the significant morbidity associated with this organism.

A Case of Liver Abscess due to Eikenella corrodens Caused by Human Bites / 감염과화학요법

Eikenella corrodens is a slow growing, facultatively anaerobic gram-negative rod that is part of the normal flora of the oral cavity and upper respiratory tracts. In most patients with E. corrodens infections, host defenses are compromised due to surgery, or chronic debilitating illness such as malignancies, or immunosuppressive therapy. This organism causes abscesses and infections that are at times fatal. We experienced a case of E. corrodens isolated from liver abscess in an immunocompetent patient. A 50-year-old man who is a dentist, was hospitalized because of fever and myalgia of 10 days' duration. Abdominal ultrasonography showed non-septated, 3.8x4.6 cm sized abscess in the segment 6/7 of the liver. E. corrodens was isolated from aspiration of liver abscess. This organism was presumably acquired from his patient's oral cavity during dental procedure. We hope that increased awareness to E. corrodens will raise the index of suspicion, and contribute to optimal management of these infections, minimizing the significant morbidity associated with this organism.

Relationship of cigarette smoking to the subgingival microbiota.

BACKGROUND: The relationship of cigarette smoking to the composition of the subgingival microbiota is not clear. Some studies indicated higher levels of certain species in smokers, while other studies failed to detect differences in the microbiota between subjects with different smoking histories. Thus, the purpose of the present investigation was to examine the prevalence, proportions and levels of the subgingival species in adult subjects who were current, past or never smokers. METHOD: 272 adult subjects ranging in age from 20-86 years with at least 20 teeth were recruited for study. Smoking history was obtained using a questionnaire. Clinical measures were taken at 6 sites per tooth at all teeth excluding third molars at a baseline visit. Subgingival plaque samples were taken from the mesial surface of all teeth excluding third molars in each subject at baseline and assayed individually for counts of 29 subgingival species using checkerboard DNA-DNA hybridization. Subjects were subset according to smoking history into never (n=124), past (n=98) and current smokers (n=50). Uni-variate and multi-variate analyses were used to seek associations between smoking category and the counts, proportions and prevalence of subgingival species. RESULTS: Greater differences were observed for the prevalence (% of sites colonized) of the test species in the 3 smoking groups than were observed for counts or proportions of total counts. Members of the orange and red complexes including E. nodatum, F. nucleatum ss vincentii, P. intermedia, P. micros, P. nigrescens, B. forsythus, P. gingivalis and T. denticola were significantly more prevalent in current smokers than in the other 2 groups. The difference in prevalence between smokers and non-smokers was due to greater colonization at sites with pocket depth <4 mm. Stepwise multiple linear regression analysis indicated that combinations of the prevalence of 5 microbial species and pack years accounted for 44% of the variance for mean pocket depth (p<0.000001), while the prevalence of 3 microbial taxa along with age, pack years, current smoking and gender accounted for 31% of the variance in mean attachment level (p<0.000001). The difference in prevalence between current and never smokers of all members of the red complex and 8 of 12 members of the orange complex was significantly greater in the maxilla than in the mandible. CONCLUSIONS: The major difference between the subgingival microbiota in subjects with different smoking history was in the prevalence of species rather than counts or proportions. The greater extent of colonization in smokers appeared to be due to greater colonization at pocket depths <4 mm. Differences in colonization patterns between current and never smokers were greater in the maxilla than in the mandible.

Profile of subgingival microbiota in children with mixed dentition.

A diversity of microbial species has been detected in children's oral flora at an early age. To investigate the composition of the subgingival microbiota of different groups of teeth in children with mixed dentition, 40 systemically healthy children, aged 7-8 years, randomly chosen, were examined. Subgingival plaque samples were taken from the mesiobuccal sites of 21, 41, 16 and 36 permanent teeth and 53, 73, 64 and 84 deciduous teeth. The samples were cultured for bacterial isolation anaerobically and in 10% CO2 plus air using selective and nonselective media. Forty-five different microbial species were isolated from both permanent and deciduous teeth. Streptococcus sanguis (79-70%), Streptococcus mitis (66-65%), Prevotella melaninogenica (51-57%), Eikenella corrodens (51-52%), Capnocytophaga gingivalis (46-34%), Capnocytophaga ochracea (45-45%), Actinomyces naeslundii (39-60%) and Prevotella intermedia (42-35%) were among the most frequently detected species in permanent and deciduous teeth respectively. Several suspected periodontal pathogens, such as Porphyromonas gingivalis, Prevotella loescheii, Campylobacter gracilis, Bacteroides forsythus, Campylobacter concisus, Peptostreptococcus micros and Selenomonas sputigena, albeit less frequently detected, were present in the microbiota of these children. The bacterial species Streptococcus constellatus, Peptostreptococcus micros, Pseudoramibacter alactolyticus, E. corrodens and Fusobacterium nucleatum were associated with non-bleeding permanent and deciduous teeth whereas Streptococcus intermedius, C. concisus, P. intermedia and P. loescheii were associated with bleeding.