Metagenomic Characterization of The Tracheobronchial Microbiome in Lung Cancer

BackgroundThe tracheobronchial and oral microbiome may be associated with lung cancer, potentially acting as predictive biomarkers. Therefore, we studied the lung and oral bacteriome and virome in non-small cell lung cancer (NSCLC) patients compared to melanoma controls to discover distinguishable features.MethodsIn this pilot case-control study, we recruited ten patients with resectable NSCLC (cases) and ten age-matched melanoma patients (controls) who both underwent tumor resection. Preoperative oral gargles were collected from both groups, who then underwent transbronchoscopic tracheal lavage after intubation. Lung tumor and adjacent non-neoplastic lung were sterilely collected after resection. Microbial DNA from all specimens underwent 16S rRNA gene sequencing. Lavage and gargle specimens underwent whole-genome shotgun sequencing. Microbiome metrics were calculated to compare both cohorts. T-tests and Wilcoxon rank sum tests were used to test for significant differences in alpha diversity between cohorts. PERMANOVA was used to compare beta diversity. ResultsNo clear differences were found in the microbial community structure of case and control gargles, but beta diversity of case and control lavages significantly differed. Two species, Granulicatella adiacens and Neisseria subflava, appeared in higher abundance in case versus control lavages. Case lavages also maintained higher relative abundances of oral commensals compared to controls. ConclusionsLung lavages demonstrated oral microbiota enrichment in cases compared to controls, suggesting microaspiration and resultant inflammation. The oral commensals Granulicatella adiacens and Neisseria subflava were more abundant in the tracheobronchial lavages of lung cancer versus melanoma patients, implicating these microorganisms as potential lung cancer biomarkers, warranting further validation studies.

Findings from the microbiota of tooth apical periodontitis and the search for pathogen forgranulomatous inflammation

BackgroundOrofacial granulomatosis (OFG) is a granulomatous inflammation (GI) disease in maxillofacial region, the underlying cause of it remains unknown. Our previous study demonstrated that tooth apical periodontitis (AP) plays a significant role in the pathogenesis of OFG, we aimed here to characterize the AP bacterial signatures of OFG patients, and identify bacteria that may be important pathogens capable of inducing OFG.ResultsThe composition of AP microbiota in OFG cases and common AP controls was compared using 16S rRNA gene sequencing, the results showed a specific AP microbiota signature in OFG patients, characterized by domination of phyla Firmicutes and Proteobacteria , notably members of Streptococcus, Lactobacillus and Neisseria. To assess the pathogenicity of the potential pathogens in OFG, we isolated and successfully in vitro cultured Streptococcus, Lactobacillus casei, Neisseria subflava, Veillonella parvula and Actinomyces from OFG patients, and injected the clinical isolates into mice respectively. Ultimately, foot pad injection with N. subflava elicited granulomatous inflammation, and the virulence of N. subflava was verified based on Koch’s postulates.ConclusionsOur findings confirmed the role of bacteria in OFG, and first suggested that the component of the host normal microbiota, N. subflava is likely a pathogen for GI.

A diagnostic challenge in clinical laboratory: Misidentification of Neisseria subflava as Neisseria meningitidis by MALDI-TOF MS

MALDI-TOF MS provides fast, easy to perform and cost-effective diagnosis in clinical microbiology laboratories, however in some cases results of MALDI-TOF MS should be confirmed with additional tests. This confirmation is especially important for causes of life-threatening infections like Neisseria meningitidis. In our laboratory, three isolates were identified as N. meningitidis by Bruker MALDI Biotyper (BD, USA) between April 2018 and March 2019 from clinical specimens of blood, sputum, and urine. 16S rRNA sequencing was performed for further investigation. Two of the isolates were identified as Neisseria subflava and only one was confirmed as N. meningitidis by sequencing. These results show that MALDI-TOF MS is not always reliable in the diagnosis of N. meningitidis and clinical microbiologists should confirm these results with additional tests. Also, clinical correlations should be determined. Accurate identification of this microorganism is very important because of the necessity of prophylactic antimicrobial usage and biosafety precautions. Enlarged databases of Neisseria species are needed to overcome this problem.

Влияние различных видов съемных конструкций и дентальных имплантатов на микробиоценоз полости рта при ортопедическом лечении

Проблема осложнений, возникающих после проведения дентальной имплантации, остается актуальной. Целью работы было исследовать влияние различных видов съемных конструкций и дентальных имплантатов на микробиоценоз полости рта при ортопедическом лечении 64 человек: 12 пациентов 1-й основной группы, 40 пациентов 2-й основной группы и 12 человек группы контроля. Через 6 месяцев после установки имплантатов в результате микробиологического исследования полости рта были выявлены различия в качественном составе микрофлоры слизистой оболочки вокруг шейки дентального имплантата. В основной группе 1 преобладали представители нормальной микрофлоры. В 100% случаев выделен Streptococcus vestibularis, более чем у половины пациентов выделены S. oralis, S. mitis, Rothia mucilaginosa, S. gordonii выделен у одного пациента. В основной группе 2 отмечено значительное разнообразие видов микроорганизмов, включая энтеробактерии, которые были выделены у 22,5% обследованных. В контрольной группе помимо представителей нормальной микрофлоры слизистой оболочки полости рта обнаружены S. vestibularis (75,5%), S. oralis (50,0%), Neisseria subflava (66,7%) и Haemophylus parainfluenzae (50,0%). У всех пациентов контрольной группы были выделены S. gordonii, а также другие виды потенциально патогенных стрептококков — S. anginosus и S. constellatus по 66,7%. Вид используемых съемных конструкций и дентальных имплантатов влияет на состав микрофлоры полости рта, а, следовательно, на дальнейший прогноз и риск развития осложнений. Съемные ортопедические конструкции с металлическим каркасом и фиксирующими элементами, телескопическими коронками и замковыми креплениями с опорой на разборные дентальные имплантаты менее других видов конструкций изменяют качественный состав микрофлоры слизистой оболочки полости рта вокруг шейки дентального имплантата.

Microbiological features of bronchial asthma and chronic obstructive pulmonary disease during remission

Background: Bronchial asthma and chronic obstructive pulmonary disease are currently the fifth leading cause of death in the world. The combination of bronchial asthma and chronic obstructive pulmonary disease seems to be a unique disease resulting from the interaction of genetic, pathological and functional factors. Aim: Study of clinical and functional parameters, bacterial spectrum in patients with combination of asthma and chronic obstructive pulmonary diseases bronchitis and non-bronchitis types. Methods: Clinical and functional examination of 69 patients with obstructive respiratory diseases, of which 49 patients with asthma combined with chronic obstructive pulmonary disease of bronchitis and non-bronchitis types. The microbiological spectrum of nasal pharynx induced by sputum was studied. Results: The following microorganisms were isolated: Staphylococcus (S. aureus, S. epidermidis), Neisseria subflava, Streptococcus (α-haemolyticus, β-haemolyticus), Streptococcus pneumoniae, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Branhamella catarrhalis, Enterococcus, Haemophilus influenzae, Candida albicans, Aspergillus spp., Actinomyces spp., Cladosporium, Penicillium, and others. Conclusion: A more pronounced quantitative content and a more diverse microbial landscape leads to a more severe course of the disease asthma combined withchronic obstructive pulmonary disease especially of the bronchitis type.

Meningitis due to a Combination of Streptococcus mitis and Neisseria subflava: A Case Report

We report a rare case of meningitis due to a combination of Streptococcus mitis and Neisseria subflava. An 80-year-old female had a 4-year history of type II diabetes mellitus (DM) and an 11-year history of rheumatoid arthritis, which was treated with prednisolone, tacrolimus, and methotrexate. One month after the removal of a dental implant, she complained of a disturbance of consciousness and suffered a convulsion. A cerebrospinal fluid culture was found to be positive for both S. mitis and N. subflava. After 14 days of antibiotic treatment with 4 g/day ceftriaxone, her stiff neck, somnolence, and laboratory data greatly improved, and she was successfully discharged at 27 days after admission. Although both S. mitis and N. subflava are generally considered to be benign bacteria, they can cause meningitis in patients with the following risk factors: older age, on immunosuppressive treatment, DM, or dental treatment.