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Gao Q, Li L, Su T, Liu J, Chen L, Yi Y, Huan Y, He J, Song C. A single-center, retrospective study of hospitalized patients with lower respiratory tract infections: clinical assessment of metagenomic next-generation sequencing and identification of risk factors in patients. Respir Res 2024; 25:250. [PMID: 38902783 PMCID: PMC11191188 DOI: 10.1186/s12931-024-02887-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 06/17/2024] [Indexed: 06/22/2024] Open
Abstract
INTRODUCTION Lower respiratory tract infections(LRTIs) in adults are complicated by diverse pathogens that challenge traditional detection methods, which are often slow and insensitive. Metagenomic next-generation sequencing (mNGS) offers a comprehensive, high-throughput, and unbiased approach to pathogen identification. This retrospective study evaluates the diagnostic efficacy of mNGS compared to conventional microbiological testing (CMT) in LRTIs, aiming to enhance detection accuracy and enable early clinical prediction. METHODS In our retrospective single-center analysis, 451 patients with suspected LRTIs underwent mNGS testing from July 2020 to July 2023. We assessed the pathogen spectrum and compared the diagnostic efficacy of mNGS to CMT, with clinical comprehensive diagnosis serving as the reference standard. The study analyzed mNGS performance in lung tissue biopsies and bronchoalveolar lavage fluid (BALF) from cases suspected of lung infection. Patients were stratified into two groups based on clinical outcomes (improvement or mortality), and we compared clinical data and conventional laboratory indices between groups. A predictive model and nomogram for the prognosis of LRTIs were constructed using univariate followed by multivariate logistic regression, with model predictive accuracy evaluated by the area under the ROC curve (AUC). RESULTS (1) Comparative Analysis of mNGS versus CMT: In a comprehensive analysis of 510 specimens, where 59 cases were concurrently collected from lung tissue biopsies and BALF, the study highlights the diagnostic superiority of mNGS over CMT. Specifically, mNGS demonstrated significantly higher sensitivity and specificity in BALF samples (82.86% vs. 44.42% and 52.00% vs. 21.05%, respectively, p < 0.001) alongside greater positive and negative predictive values (96.71% vs. 79.55% and 15.12% vs. 5.19%, respectively, p < 0.01). Additionally, when comparing simultaneous testing of lung tissue biopsies and BALF, mNGS showed enhanced sensitivity in BALF (84.21% vs. 57.41%), whereas lung tissues offered higher specificity (80.00% vs. 50.00%). (2) Analysis of Infectious Species in Patients from This Study: The study also notes a concerning incidence of lung abscesses and identifies Epstein-Barr virus (EBV), Fusobacterium nucleatum, Mycoplasma pneumoniae, Chlamydia psittaci, and Haemophilus influenzae as the most common pathogens, with Klebsiella pneumoniae emerging as the predominant bacterial culprit. Among herpes viruses, EBV and herpes virus 7 (HHV-7) were most frequently detected, with HHV-7 more prevalent in immunocompromised individuals. (3) Risk Factors for Adverse Prognosis and a Mortality Risk Prediction Model in Patients with LRTIs: We identified key risk factors for poor prognosis in lower respiratory tract infection patients, with significant findings including delayed time to mNGS testing, low lymphocyte percentage, presence of chronic lung disease, multiple comorbidities, false-negative CMT results, and positive herpesvirus affecting patient outcomes. We also developed a nomogram model with good consistency and high accuracy (AUC of 0.825) for predicting mortality risk in these patients, offering a valuable clinical tool for assessing prognosis. CONCLUSION The study underscores mNGS as a superior tool for lower respiratory tract infection diagnosis, exhibiting higher sensitivity and specificity than traditional methods.
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Affiliation(s)
- Qinghua Gao
- Department of Pulmonary and Critical Care Medicine, Anning First People's Hospital Affiliated to Kunming University of Science and Technology, Kunming, 650302, China
| | - Lingyi Li
- Department of Medical, Hangzhou Matridx Biotechnology, Hangzhou, 311100, China
| | - Ting Su
- Department of Pulmonary and Critical Care Medicine, Anning First People's Hospital Affiliated to Kunming University of Science and Technology, Kunming, 650302, China
| | - Jie Liu
- Department of Pulmonary and Critical Care Medicine, Anning First People's Hospital Affiliated to Kunming University of Science and Technology, Kunming, 650302, China
| | - Liping Chen
- Department of Pulmonary and Critical Care Medicine, Anning First People's Hospital Affiliated to Kunming University of Science and Technology, Kunming, 650302, China
| | - Yongning Yi
- Department of Pulmonary and Critical Care Medicine, Anning First People's Hospital Affiliated to Kunming University of Science and Technology, Kunming, 650302, China
| | - Yun Huan
- Department of Pulmonary and Critical Care Medicine, Anning First People's Hospital Affiliated to Kunming University of Science and Technology, Kunming, 650302, China
| | - Jian He
- Department of Pulmonary and Critical Care Medicine, Anning First People's Hospital Affiliated to Kunming University of Science and Technology, Kunming, 650302, China.
| | - Chao Song
- Department of Medical Imaging, Anning First People's Hospital Affiliated to Kunming University of Science and Technology, Kunming, 650302, China.
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Wang N, Gao Z, He S, Han M, Han W, Liu X, Cao H, Jing M, Sun T, Xu J. Lung abscess by Fusobacterium nucleatum and Streptococcus spp. co-infection by mNGS: A case series. Open Life Sci 2023; 18:20220651. [PMID: 37483431 PMCID: PMC10358748 DOI: 10.1515/biol-2022-0651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 05/15/2023] [Accepted: 06/05/2023] [Indexed: 07/25/2023] Open
Abstract
A lung abscess is a necrotizing infection caused by microbiomes that lead to the loss of healthy lung tissue. The routine culture is a waste of time and yields false-negative results, and clinicians could only choose empiric therapy or use broad-spectrum antibiotics, which could significantly contribute to the problem of resistance or aggravate the condition. We report three patients with a routine-culture-negative lung abscess. The presenting symptoms included fever, cough, dyspnea, and chest pain, and a computed tomography scan revealed a lesion in the lungs. The bronchoalveolar lavage fluid and pleural fluid were tested for pathogens using metagenome next-generation sequencing (mNGS), and the results revealed Fusobacterium nucleatum and Streptococcus spp. (S. constellatus, S. intermedius) as the most represented microbial pathogens. Our data demonstrated that mNGS could be a promising alternative diagnostic tool for pathogen detection, and the pathogen lists indicate that it will be important to focus on the Streptococcus genus rather than the dominant Streptococcus spp. in terms of co-infection of pathogen determined by shotgun mNGS.
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Affiliation(s)
- Na Wang
- Department of Breast Medicine, Cancer Hospital of China Medical University, Liaoning Cancer Hospital, Shenyang, 110042, China
- Department of Pharmacology, Cancer Hospital of China Medical University, Liaoning Cancer Hospital, Shenyang, 110042, China
| | - Zhichao Gao
- Department of Breast Medicine, Cancer Hospital of China Medical University, Liaoning Cancer Hospital, Shenyang, 110042, China
- Department of Breast Medicine, Cancer Hospital of Dalian University of Technology, Liaoning Cancer Hospital, Shenyang, 110042, China
| | - Shuai He
- Department of Imaging, Cancer Hospital of Dalian University of Technology, Liaoning Cancer Hospital, Shenyang, 110042, China
| | - Mengzhen Han
- Department of Breast Medicine, Cancer Hospital of China Medical University, Liaoning Cancer Hospital, Shenyang, 110042, China
- Department of Pharmacology, Cancer Hospital of China Medical University, Liaoning Cancer Hospital, Shenyang, 110042, China
| | - Wenjie Han
- Department of Breast Medicine, Cancer Hospital of China Medical University, Liaoning Cancer Hospital, Shenyang, 110042, China
- Department of Pharmacology, Cancer Hospital of China Medical University, Liaoning Cancer Hospital, Shenyang, 110042, China
| | - Xiaolin Liu
- Liaoning Kanghui Biotechnology Co., Ltd, Zhihuier Street, Hunnan District, Shenyang, 110001, China
| | - Hui Cao
- Department of Breast Medicine, Cancer Hospital of China Medical University, Liaoning Cancer Hospital, Shenyang, 110042, China
- Department of Breast Medicine, Cancer Hospital of Dalian University of Technology, Liaoning Cancer Hospital, Shenyang, 110042, China
| | - Mingxi Jing
- Department of Breast Medicine, Cancer Hospital of China Medical University, Liaoning Cancer Hospital, Shenyang, 110042, China
- Department of Breast Medicine, Cancer Hospital of Dalian University of Technology, Liaoning Cancer Hospital, Shenyang, 110042, China
| | - Tao Sun
- Department of Breast Medicine, Cancer Hospital of China Medical University, Liaoning Cancer Hospital, Shenyang, 110042, China
- Department of Breast Medicine, Cancer Hospital of Dalian University of Technology, Liaoning Cancer Hospital, Shenyang, 110042, China
| | - Junnan Xu
- Department of Breast Medicine, Cancer Hospital of China Medical University, Liaoning Cancer Hospital, Shenyang, 110042, China
- Department of Pharmacology, Cancer Hospital of China Medical University, Liaoning Cancer Hospital, Shenyang, 110042, China
- Department of Breast Medicine, Cancer Hospital of Dalian University of Technology, Liaoning Cancer Hospital, Shenyang, 110042, China
- Department of Medical Oncology, Cancer Hospital of Dalian University of Technology, Liaoning Cancer Hospital and Institute, No. 44 Xiaoheyan Road, Dadong District, Shenyang, Liaoning110042, P. R. China
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Noguchi S, Yatera K, Kawanami T, Ikegami H, Hata R, Yamasaki K, Fukuda K, Mukae H. Association between obligatory anaerobes and empyema caused by Streptococcus anginosus group bacteria. Respir Investig 2021; 59:686-690. [PMID: 34120847 DOI: 10.1016/j.resinv.2021.04.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 04/20/2021] [Accepted: 04/25/2021] [Indexed: 11/25/2022]
Abstract
Co-infections of Streptococcus anginosus group (SAG) bacteria and obligate anaerobes are observed in patients with empyema; however, their epidemiology and pathology remain unknown. A retrospective study was performed with 44 patients who underwent pleural effusion microbiota evaluation between January 2006 and March 2018, using the clone library method for detecting empyema caused by SAG bacteria. Based on culture analysis of pleural effusion, 12 patients were diagnosed with empyema caused by SAG bacteria. Obligate anaerobe phylotypes were detected in eight patients (66.7%) using the clone library method, whereas anaerobic culture analysis detected anaerobes in only two patients (16.7%). No significant difference was observed between the clinical features of SAG-mediated empyema with and without anaerobes using the clone library method, except for chest computed tomographic data. Co-infection of SAG bacteria and obligate anaerobes may be underestimated if conventional culture methods are used. SAG-mediated empyema with and without anaerobes may present different radiological features; therefore, further studies are required.
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Affiliation(s)
- Shingo Noguchi
- Department of Respiratory Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishiku, Kitakyushu City, Fukuoka, 807-8555, Japan.
| | - Kazuhiro Yatera
- Department of Respiratory Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishiku, Kitakyushu City, Fukuoka, 807-8555, Japan
| | - Toshinori Kawanami
- Department of Respiratory Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishiku, Kitakyushu City, Fukuoka, 807-8555, Japan
| | - Hiroaki Ikegami
- Department of Respiratory Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishiku, Kitakyushu City, Fukuoka, 807-8555, Japan
| | - Ryosuke Hata
- Department of Respiratory Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishiku, Kitakyushu City, Fukuoka, 807-8555, Japan
| | - Kei Yamasaki
- Department of Respiratory Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishiku, Kitakyushu City, Fukuoka, 807-8555, Japan
| | - Kazumasa Fukuda
- Department of Microbiology, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishiku, Kitakyushu City, Fukuoka, 807-8555, Japan
| | - Hiroshi Mukae
- Department of Respiratory Medicine, Unit of Translational Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki City, Nagasaki, 852-8501, Japan
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Determination of the Role of Fusobacterium Nucleatum in the Pathogenesis in and Out the Mouth. ACTA ACUST UNITED AC 2021; 41:87-99. [PMID: 32573481 DOI: 10.2478/prilozi-2020-0026] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
INTRODUCTION One of the most important types of microorganisms in the oral cavity in both healthy and non-healthy individuals is Fusobacterium nucleatum. Although present as a normal resident in the oral cavity, this Gram-negative pathogen is dominant in periodontal disease and it is involved in many invasive infections in the population, acute and chronic inflammatory conditions, as well as many adverse events with a fatal outcome. AIM To determine the role of F. nucleatum in the development of polymicrobial biofilms thus pathogenic changes in and out of the oral media. MATERIAL AND METHOD A systematic review of the literature concerning the determination and role of F. nucleatum through available clinical trials, literature reviews, original research and articles published electronically at Pub Med and Google Scholar. CONCLUSION The presence of Fusobacterium nucleatum is commonly associated with the health status of individuals. These anaerobic bacteria plays a key role in oral pathological conditions and has been detected in many systemic disorders causing complex pathogenethic changes probably due to binding ability to various cells thus several virulence mechanisms. Most common diseases and conditions in the oral cavity associated with F.nucleatum are gingivitis (G), chronic periodontitis (CH), aggressive periodontitis (AgP), endo-periodental infections (E-P), chronic apical periodontitis (PCHA). The bacterium has been identified and detected in many systemic disorders such as coronary heart disease (CVD) pathological pregnancy (P); polycystic ovary syndrome (PCOS), high-risk pregnancy (HRP), colorectal cancer (CRC); pre-eclampsia (PE); rheumatoid arthritis (RA); osteoarthritis (OA).
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Thymoquinone inhibits biofilm formation and virulence properties of periodontal bacteria. Arch Oral Biol 2020; 115:104744. [PMID: 32416351 DOI: 10.1016/j.archoralbio.2020.104744] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 03/27/2020] [Accepted: 04/30/2020] [Indexed: 01/05/2023]
Abstract
OBJECTIVES To evaluate the effects of thymoquinone (TQ) on biofilm formation, hemolysis, hydrogen sulfide (H2S) production and expression of virulence factors of Fusobacterium nucleatum and Porphyromonas gingivalis. MATERIALS AND METHODS Reference strains of F. nucleatum ATCC 25586 and P. gingivalis A7436 were tested in our study. The minimum inhibitory concentration (MIC) of TQ was determined by broth microdilution method. The impacts of TQ on virulence properties of the periodontal bacteria including biofilm formation, hemolysis and H2S activities were studied. Quantitative RT-PCR was performed to evaluate the expression levels of key virulence factors including outer membrane proteins (aim-1, fadA) in F. nucleatum as well as cysteine proteinases or gingipains (rgpA, rgpB, kgp) and fimbriae (fimA, mfa1) in P. gingivalis. RESULTS The MIC of TQ were 12.5 and 1.56 μg/mL in F. nucleatum and P. gingivalis, respectively. The sub-MIC concentrations of TQ could prevent biofilm formation and hemolysis activities of both bacteria. TQ also inhibited H2S production which is highly associated with oral malodour. Scanning electron microscopy revealed that TQ could disrupt bacterial membrane and led to cell lysis. Furthermore, TQ reduced the expression of major virulence factors tested in F. nucleatum and P. gingivalis. CONCLUSIONS The TQ had potent antibacterial effect and could attenuate virulence properties of F. nucleatum and P. gingivalis. Therefore, TQ has the potential to be developed and used in periodontal treatments, especially to prevent the progression of periodontitis.
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Sun CH, Li BB, Wang B, Zhao J, Zhang XY, Li TT, Li WB, Tang D, Qiu MJ, Wang XC, Zhu CM, Qian ZR. The role of Fusobacterium nucleatum in colorectal cancer: from carcinogenesis to clinical management. Chronic Dis Transl Med 2019; 5:178-187. [PMID: 31891129 PMCID: PMC6926109 DOI: 10.1016/j.cdtm.2019.09.001] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Indexed: 02/06/2023] Open
Abstract
Colorectal cancer (CRC) is a common malignant tumor that affects people worldwide. Metagenomic analyses have shown an enrichment of Fusobacterium nucleatum (F. nucleatum) in colorectal carcinoma tissue; many studies have indicated that F. nucleatum is closely related to the colorectal carcinogenesis. In this review, we provide the latest information to reveal the related molecular mechanisms. The known virulence factors of F. nucleatum promote adhesion to intestinal epithelial cells via FadA and Fap2. Besides, Fap2 also binds to immune cells causing immunosuppression. Furthermore, F. nucleatum recruits tumor-infiltrating immune cells, thus yielding a pro-inflammatory microenvironment, which promotes colorectal neoplasia progression. F. nucleatum was also found to potentiate CRC development through toll-like receptor 2 (TLR2)/toll-like receptor 4 (TLR4) signaling and microRNA (miRNA)-21 expression. In addition, F. nucleatum increases CRC recurrence along with chemoresistance by mediating a molecular network of miRNA-18a*, miRNA-4802, and autophagy components. Moreover, viable F. nucleatum was detected in mouse xenografts of human primary colorectal adenocarcinomas through successive passages. These findings indicated that an increased number of F. nucleatum in the tissues is a biomarker for the diagnosis and prognosis of CRC, and the underlying molecular mechanism can probably provide a potential intervention treatment strategy for patients with F. nucleatum-associated CRC.
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Affiliation(s)
- Chun-Hui Sun
- Equipe Communication Intercellulaire et Infections Microbiennes, Centre de Recherche Interdisciplinaire en Biologie (CIRB), Collège de France, Paris 75005, France.,Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong 518107, China
| | - Bin-Bin Li
- Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong 518107, China.,School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Bo Wang
- Department of Oncology, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong 518107, China
| | - Jing Zhao
- Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong 518107, China
| | - Xiao-Ying Zhang
- Health Management Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong 518107, China
| | - Ting-Ting Li
- Department of Gastroenterology, The Second Medical Center of Chinese PLA General Hospital, Beijing 100853, China
| | - Wen-Bing Li
- Department of Pathology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100021, China
| | - Di Tang
- Department of General Surgery, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong 518107, China
| | - Miao-Juan Qiu
- Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong 518107, China
| | - Xin-Cheng Wang
- Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong 518107, China
| | - Cheng-Ming Zhu
- Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong 518107, China
| | - Zhi-Rong Qian
- Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong 518107, China
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Denes E, Barraud O. Fusobacterium nucleatum infections: clinical spectrum and bacteriological features of 78 cases. Infection 2016; 44:475-81. [PMID: 26783023 DOI: 10.1007/s15010-015-0871-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 12/31/2015] [Indexed: 12/12/2022]
Abstract
PURPOSE Few series describe the clinical spectrum of Fusobacterium spp. infections. Among them, fewer discuss F. nucleatum, even though there are many clinical cases. METHODS We performed a retrospective study over 8 years (from 2007 to 2014) in Limoges University Hospital, France, to assess clinical and bacteriological aspects of infections due to F. nucleatum. RESULTS Eighty-one patients with F. nucleatum positive cultures were included in this study, irrespective of sample origin. Abscesses (n = 43), bacteraemia (n = 18) and bone infections (n = 8) were the most common types of infections, Abscesses were found in various organs (mostly skin, brain, pleura, liver). Co-morbidities were found in 38 patients (47 %) with neoplasia, diabetes, and alcoholism and history of smoking. There were more neoplasms in patients with bacteraemia than in patients with abscesses (p = 0.007). In 51 cases (65.4 %), infection was polymicrobial, either during bacteraemia or abscesses. Main associations were with Streptococcus spp., Peptostreptococcus spp. and/or Prevotella spp. The sources of infection, when found, were either dental or gastrointestinal. All isolates were susceptible to penicillin, clindamycin and metronidazole. CONCLUSIONS Infections involving F. nucleatum are uncommon and potentially severe, with many abscesses requiring surgery. Bacteraemia was mainly associated with co-morbidities such as cancer. Polymicrobial infections were very common and there is probably interaction and/or synergy between F. nucleatum and some other commensal bacteria to cause infections and abscesses.
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Affiliation(s)
- E Denes
- Infectious Diseases Department, CHU Limoges, 87000, Limoges, France.
| | - O Barraud
- University of Limoges, UMR_S 1092, 87000, Limoges, France
- INSERM, U1092, 87000, Limoges, France
- Laboratoire de Bactériologie-Virologie-Hygiène, CHU Limoges, 87000, Limoges, France
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Morphology-Independent Virulence of Candida Species during Polymicrobial Intra-abdominal Infections with Staphylococcus aureus. Infect Immun 2015; 84:90-8. [PMID: 26483410 DOI: 10.1128/iai.01059-15] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 10/10/2015] [Indexed: 01/04/2023] Open
Abstract
Intra-abdominal polymicrobial infections cause significant morbidity and mortality. An experimental mouse model of Candida albicans-Staphylococcus aureus intra-abdominal infection (IAI) results in 100% mortality by 48 to 72 h postinoculation, while monomicrobial infections are avirulent. Mortality is associated with robust local and systemic inflammation without a requirement for C. albicans morphogenesis. However, the contribution of virulence factors coregulated during the yeast-to-hypha transition is unknown. This also raised the question of whether other Candida species that are unable to form hyphae are as virulent as C. albicans during polymicrobial IAI. Therefore, the purpose of this study was to evaluate the ability of non-albicans Candida (NAC) species with various morphologies and C. albicans transcription factor mutants (efg1/efg1 and cph1/cph1) to induce synergistic mortality and the accompanying inflammation. Results showed that S. aureus coinoculated with C. krusei or C. tropicalis was highly lethal, similar to C. albicans, while S. aureus-C. dubliniensis, S. aureus-C. parapsilosis, and S. aureus-C. glabrata coinoculations resulted in little to no mortality. Local and systemic interleukin-6 (IL-6) and prostaglandin E2 (PGE2) levels were significantly elevated during symptomatic and/or lethal coinfections, and hypothermia strongly correlated with mortality. Coinoculation with C. albicans strains deficient in the transcription factor Efg1 but not Cph1 reversed the lethal outcome. These results support previous findings and demonstrate that select Candida species, without reference to any morphological requirement, induce synergistic mortality, with IL-6 and PGE2 acting as key inflammatory factors. Mechanistically, signaling pathways controlled by Efg1 are critical for the ability of C. albicans to induce mortality from an intra-abdominal polymicrobial infection.
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Han YW. Fusobacterium nucleatum: a commensal-turned pathogen. Curr Opin Microbiol 2015; 23:141-7. [PMID: 25576662 DOI: 10.1016/j.mib.2014.11.013] [Citation(s) in RCA: 459] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 11/17/2014] [Accepted: 11/18/2014] [Indexed: 12/11/2022]
Abstract
Fusobacterium nucleatum is an anaerobic oral commensal and a periodontal pathogen associated with a wide spectrum of human diseases. This article reviews its implication in adverse pregnancy outcomes (chorioamnionitis, preterm birth, stillbirth, neonatal sepsis, preeclampsia), GI disorders (colorectal cancer, inflammatory bowel disease, appendicitis), cardiovascular disease, rheumatoid arthritis, respiratory tract infections, Lemierre's syndrome and Alzheimer's disease. The virulence mechanisms involved in the diseases are discussed, with emphasis on its colonization, systemic dissemination, and induction of host inflammatory and tumorigenic responses. The FadA adhesin/invasin conserved in F. nucleatum is a key virulence factor and a potential diagnostic marker for F. nucleatum-associated diseases.
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Affiliation(s)
- Yiping W Han
- Division of Periodontics, Section of Oral Diagnostics & Sciences, College of Dental Medicine, Columbia University Medical Center, United States; Department of Microbiology & Immunology, College of Physicians & Surgeons, Columbia University Medical Center, United States; Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, United States.
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Abstract
Acute apical abscess is the most common form of dental abscess and is caused by infection of the root canal of the tooth. It is usually localized intraorally, but in some cases the apical abscess may spread and result in severe complications or even mortality. The reasons why dental root canal infections can become symptomatic and evolve to severe spreading and sometimes life-threatening abscesses remain elusive. Studies using culture and advanced molecular microbiology methods for microbial identification in apical abscesses have demonstrated a multispecies community conspicuously dominated by anaerobic bacteria. Species/phylotypes commonly found in these infections belong to the genera Fusobacterium, Parvimonas, Prevotella, Porphyromonas, Dialister, Streptococcus, and Treponema. Advances in DNA sequencing technologies and computational biology have substantially enhanced the knowledge of the microbiota associated with acute apical abscesses and shed some light on the etiopathogeny of this disease. Species richness and abundance and the resulting network of interactions among community members may affect the collective pathogenicity and contribute to the development of acute infections. Disease modifiers, including transient or permanent host-related factors, may also influence the development and severity of acute abscesses. This review focuses on the current evidence about the etiology and treatment of acute apical abscesses and how the process is influenced by host-related factors and proposes future directions in research, diagnosis, and therapeutic approaches to deal with this disease.
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Candida albicans-Staphylococcus aureus polymicrobial peritonitis modulates host innate immunity. Infect Immun 2013; 81:2178-89. [PMID: 23545303 DOI: 10.1128/iai.00265-13] [Citation(s) in RCA: 112] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Despite advances in medical device fabrication and antimicrobial treatment therapies, fungal-bacterial polymicrobial peritonitis remains a serious complication for surgery patients, those on peritoneal dialysis, and the critically ill. Using a murine model of peritonitis, we have demonstrated that monomicrobial infection with Candida albicans or Staphylococcus aureus is nonlethal. However, coinfection with these same doses leads to a 40% mortality rate and increased microbial burden in the spleen and kidney by day 1 postinfection. Using a multiplex enzyme-linked immunosorbent assay, we have also identified a unique subset of innate proinflammatory cytokines (interleukin-6, granulocyte colony-stimulating factor, keratinocyte chemoattractant, monocyte chemoattractant protein-1, and macrophage inflammatory protein-1α) that are significantly increased during polymicrobial versus monomicrobial peritonitis, leading to increased inflammatory infiltrate into the peritoneum and target organs. Treatment of coinfected mice with the cyclooxygenase (COX) inhibitor indomethacin reduces the infectious burden, proinflammatory cytokine production, and inflammatory infiltrate while simultaneously preventing any mortality. Further experiments demonstrated that the immunomodulatory eicosanoid prostaglandin E2 (PGE2) is synergistically increased during coinfection compared to monomicrobial infection; indomethacin treatment also decreased elevated PGE2 levels. Furthermore, addition of exogenous PGE2 into the peritoneal cavity during infection overrode the protection provided by indomethacin and restored the increased mortality and microbial burden. Importantly, these studies highlight the ability of fungal-bacterial coinfection to modulate innate inflammatory events with devastating consequences to the host.
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Sano N, Yamashita Y, Fukuda K, Taniguchi H, Goto M, Miyamoto H. Comprehensive Analysis of Bacterial Flora in Postoperative Maxillary Cyst Fluid by 16S rRNA Gene and Culture Methods. ISRN DENTISTRY 2012; 2012:840483. [PMID: 22685668 PMCID: PMC3364584 DOI: 10.5402/2012/840483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Accepted: 02/16/2012] [Indexed: 11/24/2022]
Abstract
Intracystic fluid was aseptically collected from 11 patients with postoperative maxillary cyst (POMC), and DNA was extracted from the POMC fluid. Bacterial species were identified by sequencing after cloning of approximately 580 bp of the 16S rRNA gene. Identification of pathogenic bacteria was also performed by culture methods. The phylogenetic identity was determined by sequencing 517–596 bp in each of the 1139 16S rRNA gene clones. A total of 1114 clones were classified while the remaining 25 clones were unclassified. A total of 103 bacterial species belonging to 42 genera were identified in POMC fluid samples by 16S rRNA gene analysis. Species of Prevotella (91%), Neisseria (73%), Fusobacterium (73%), Porphyromonas (73%), and Propionibacterium (73%) were found to be highly prevalent in all patients. Streptococcus mitis (64%), Fusobacterium nucleatum (55%), Propionibacterium acnes (55%), Staphylococcus capitis (55%), and Streptococcus salivarius (55%) were detected in more than 6 of the 11 patients. The results obtained by the culture method were different from those obtained by 16S rRNA gene analysis, but both approaches may be necessary for the identification of pathogens, especially of bacteria that are difficult to detect by culture methods, and the development of rational treatments for patients with POMC.
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Affiliation(s)
- Naoto Sano
- Department of Oral and Maxillofacial Surgery, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501, Japan
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Polak D, Shapira L, Weiss EI, Houri-Haddad Y. The role of coaggregation between Porphyromonas gingivalis and Fusobacterium nucleatum on the host response to mixed infection. J Clin Periodontol 2012; 39:617-25. [PMID: 22607053 DOI: 10.1111/j.1600-051x.2012.01889.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/24/2012] [Indexed: 11/30/2022]
Abstract
AIM To evaluate the role of coaggregation between Porphyromonas gingivalis and Fusobacterium nucleatum on the virulence of the mixed infection in mice. MATERIALS AND METHODS Inhibition of coaggregation was carried out using lactose. In vitro, inhibition of coaggregation was verified using a coaggregation assay. In vivo, the virulence of the mixed infection, with and without coaggregation, was examined in a model of experimental periodontitis in mice. The local host response to the mixed infection, with or without coaggregation, was examined using the subcutaneous chamber model of infection. RESULTS Lactose inhibited the coaggregation between P. gingivalis and F. nucleatum at all the tested concentrations (1-0.0625 M). Surprisingly, the addition of lactose to the mixed infection increased the severity of experimental periodontitis (as measured by alveolar bone loss) compared with mixed infection with coaggregating bacteria. The addition of lactose to the mixed infection resulted in mild attenuation of TNFα and IL-1β levels. In addition, inhibition of coaggregation resulted in inhibition of the phagocytosis of F. nucleatum and augmentation of the phagocytosis of P. gingivalis. CONCLUSIONS The ability of P. gingivalis and F. nucleatum to coaggregate may limit their ability to induce experimental periodontitis in a mixed infection model. Moreover, there is a shift in the phagocytosis pattern of the bacteria with the annulment of coaggregeaiton, with a reduction in F. nucleatum phagocytosis and amplification of P. gingivalis phagocytosis. The increased virulence of the mixed infection without coaggregation may surprisingly lay in the sustention of F. nucleatum in the infected sites.
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Affiliation(s)
- David Polak
- Department of Periodontology, The Hebrew University-Hadassah Medical center, Jerusalem, Israel.
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Nohrström E, Mattila T, Pettilä V, Kuusela P, Carlson P, Kentala E, Mattila PS. Clinical spectrum of bacteraemic Fusobacterium infections: from septic shock to nosocomial bacteraemia. ACTA ACUST UNITED AC 2011; 43:463-70. [PMID: 21391770 DOI: 10.3109/00365548.2011.565071] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Fusobacterium species are anaerobic bacteria that relatively rarely cause sepsis with a variable clinical presentation. METHODS We reviewed the records of 52 consecutive patients who had Fusobacterium bacteraemia over a 10-y period. RESULTS The clinical pictures could be classified into 4 groups: (1) patients who had Lemierre's syndrome with Fusobacterium necrophorum sepsis and internal jugular vein thrombosis, n = 5 (10%); (2) previously healthy patients who had F. necrophorum sepsis without any signs of macroscopic vascular thrombosis (but 5 of them had abscesses), n = 14 (27%); (3) women who had puerperal infections, n = 6 (12%); and (4) patients who were on average older than the patients in the previous groups, who had cardiovascular, pulmonary, neoplastic, or other underlying diseases, n = 27 (52%). Of these latter 27 patients, 23 had nosocomial Fusobacterium nucleatum bacteraemia presenting as a febrile illness associated with chemotherapy or instrumentation. CONCLUSIONS Patients with chronic underlying diseases are more likely to be infected with F. nucleatum than F. necrophorum. F. nucleatum bacteraemia may present as a febrile illness without severe symptoms. F. necrophorum caused sepsis mainly in previously healthy individuals. These infections may be accompanied with a jugular vein thrombosis characteristic of Lemierre's syndrome and septic shock. However, F. necrophorum infections present more frequently without any apparent venous thrombosis and may be accompanied by abscesses.
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Affiliation(s)
- Elina Nohrström
- Department of Otorhinolaryngology, Helsinki University Central Hospital, Haartmaninkatu, Helsinki, Finland
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15
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Abstract
Animal models and cell cultures have contributed new knowledge in biological sciences, including periodontology. Although cultured cells can be used to study physiological processes that occur during the pathogenesis of periodontitis, the complex host response fundamentally responsible for this disease cannot be reproduced in vitro. Among the animal kingdom, rodents, rabbits, pigs, dogs, and nonhuman primates have been used to model human periodontitis, each with advantages and disadvantages. Periodontitis commonly has been induced by placing a bacterial plaque retentive ligature in the gingival sulcus around the molar teeth. In addition, alveolar bone loss has been induced by inoculation or injection of human oral bacteria (e.g., Porphyromonas gingivalis) in different animal models. While animal models have provided a wide range of important data, it is sometimes difficult to determine whether the findings are applicable to humans. In addition, variability in host responses to bacterial infection among individuals contributes significantly to the expression of periodontal diseases. A practical and highly reproducible model that truly mimics the natural pathogenesis of human periodontal disease has yet to be developed.
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16
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Differential ability of periodontopathic bacteria to modulate invasion of human gingival epithelial cells by Porphyromonas gingivalis. Microb Pathog 2009; 47:329-33. [DOI: 10.1016/j.micpath.2009.09.012] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Revised: 09/23/2009] [Accepted: 09/25/2009] [Indexed: 11/17/2022]
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17
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Ecological consequences of ingestion of Bacillus cereus on Bacillus thuringiensis infections and on the gut flora of a lepidopteran host. J Invertebr Pathol 2008; 99:103-11. [DOI: 10.1016/j.jip.2008.04.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2008] [Revised: 04/18/2008] [Accepted: 04/22/2008] [Indexed: 11/19/2022]
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Affiliation(s)
- Denis F Kinane
- Center for Oral Health and Systemic Disease, University of Louisville School of Dentistry, Louisville, KY, USA
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19
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Karpathy SE, Qin X, Gioia J, Jiang H, Liu Y, Petrosino JF, Yerrapragada S, Fox GE, Haake SK, Weinstock GM, Highlander SK. Genome sequence of Fusobacterium nucleatum subspecies polymorphum - a genetically tractable fusobacterium. PLoS One 2007; 2:e659. [PMID: 17668047 PMCID: PMC1924603 DOI: 10.1371/journal.pone.0000659] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2007] [Accepted: 06/26/2007] [Indexed: 11/19/2022] Open
Abstract
Fusobacterium nucleatum is a prominent member of the oral microbiota and is a common cause of human infection. F. nucleatum includes five subspecies: polymorphum, nucleatum, vincentii, fusiforme, and animalis. F. nucleatum subsp. polymorphum ATCC 10953 has been well characterized phenotypically and, in contrast to previously sequenced strains, is amenable to gene transfer. We sequenced and annotated the 2,429,698 bp genome of F. nucleatum subsp. polymorphum ATCC 10953. Plasmid pFN3 from the strain was also sequenced and analyzed. When compared to the other two available fusobacterial genomes (F. nucleatum subsp. nucleatum, and F. nucleatum subsp. vincentii) 627 open reading frames unique to F. nucleatum subsp. polymorphum ATCC 10953 were identified. A large percentage of these mapped within one of 28 regions or islands containing five or more genes. Seventeen percent of the clustered proteins that demonstrated similarity were most similar to proteins from the clostridia, with others being most similar to proteins from other gram-positive organisms such as Bacillus and Streptococcus. A ten kilobase region homologous to the Salmonella typhimurium propanediol utilization locus was identified, as was a prophage and integrated conjugal plasmid. The genome contains five composite ribozyme/transposons, similar to the CdISt IStrons described in Clostridium difficile. IStrons are not present in the other fusobacterial genomes. These findings indicate that F. nucleatum subsp. polymorphum is proficient at horizontal gene transfer and that exchange with the Firmicutes, particularly the Clostridia, is common.
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Affiliation(s)
- Sandor E. Karpathy
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Microbiology and Molecular Genetics, University of Texas Medical School, Houston, Texas, United States of America
| | - Xiang Qin
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, United States of America
| | - Jason Gioia
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Huaiyang Jiang
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, United States of America
| | - Yamei Liu
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, United States of America
| | - Joseph F. Petrosino
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Shailaja Yerrapragada
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, United States of America
| | - George E. Fox
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, United States of America
| | - Susan Kinder Haake
- Associated Clinical Specialties, University of California at Los Angeles School of Dentistry, Los Angeles, California, United States of America
| | - George M. Weinstock
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Microbiology and Molecular Genetics, University of Texas Medical School, Houston, Texas, United States of America
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Sarah K. Highlander
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
- * To whom correspondence should be addressed. E-mail:
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Yamaura M, Sato T, Echigo S, Takahashi N. Quantification and detection of bacteria from postoperative maxillary cyst by polymerase chain reaction. ACTA ACUST UNITED AC 2005; 20:333-8. [PMID: 16238591 DOI: 10.1111/j.1399-302x.2005.00229.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND/AIMS Postoperative maxillary cyst (POMC) is known to occur as a delayed complication of radical maxillary sinus surgery, such as Caldwell-Luc surgery. The cyst gradually expands with no symptoms over a period of years, and then occasionally causes swelling and pain in the buccal region and/or the mucogingival fold. It is probable that bacterial infection affects the progression of POMC symptoms. The aims of this study were to determine the bacterial density and to examine the presence of 20 oral bacteria in POMC fluids. METHODS POMC fluids (4 purulent, 2 mucous and 4 serous) were sampled from 10 subjects (aged 43-77 years). Bacterial quantification and detection were performed by real-time polymerase chain reaction (PCR) and nested PCR based on bacterial 16S rRNA genes, respectively. RESULTS Bacterial DNA was detected in all samples and the average concentrations of bacterial DNA were 5.9 (purulent), 0.5 (mucous), and 0.7 (serous) ng/mg of sample. Twelve bacterial species, including anginosus streptococci, known to be associated with abscess formation, were detected in the purulent fluids, while two and five species were detected in the mucous and serous fluids, respectively. CONCLUSION Purulent fluids contained numerous bacteria of various types, thus suggesting that oral bacteria may cause symptoms such as pain in POMC with purulent fluids. Mucous and serous fluids also contained bacteria, although their numbers were small, thus suggesting an association between bacteria and progression of POMC.
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Affiliation(s)
- M Yamaura
- Division of Oral Surgery, Tohoku University Graduate School of Dentistry, Sendai, Japan
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21
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Brook I, Lewis MAO, Sándor GKB, Jeffcoat M, Samaranayake LP, Vera Rojas J. Clindamycin in dentistry: More than just effective prophylaxis for endocarditis? ACTA ACUST UNITED AC 2005; 100:550-8. [PMID: 16243239 DOI: 10.1016/j.tripleo.2005.02.086] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2004] [Revised: 02/15/2005] [Accepted: 02/24/2005] [Indexed: 10/25/2022]
Abstract
Clindamycin is a broad-spectrum antibiotic with activity against aerobic, anaerobic, and beta-lactamase-producing pathogens. This antibiotic has been used for many years as prophylactic treatment during dental procedures to prevent endocarditis. However, the spectrum and susceptibility of the bacteria species involved in dental infections indicate that clindamycin would also be an effective treatment option for these conditions. In addition to its antiinfective properties, clindamycin has high oral absorption, significant tissue penetration, including penetration into bone, and stimulatory effects on the host immune system. This review discusses the microbiologic and clinical evidence supporting the efficacy and safety of clindamycin for the successful management of dental infections.
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22
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Silva VL, Diniz CG, Cara DC, Santos SG, Nicoli JR, Carvalho MAR, Farias LM. Enhanced pathogenicity of Fusobacterium nucleatum adapted to oxidative stress. Microb Pathog 2005; 39:131-8. [PMID: 16125361 DOI: 10.1016/j.micpath.2005.07.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2005] [Revised: 07/11/2005] [Accepted: 07/19/2005] [Indexed: 11/23/2022]
Abstract
Fusobacterium nucleatum is an obligate anaerobic bacterium found in the indigenous human microbiota but also recovered from several anaerobic infections. Considering the biological and medical relevance of F. nucleatum, the characterization of its response to oxidative stress is needed in order to understand how this anaerobic bacterium survives during an invasive process of oxygenated tissues. Influence of oxidative stress by atmospheric oxygen exposure on cellular morphology and pathogenicity of F. nucleatum were investigated. The wild-type F. nucleatum ATCC 25586 (wt-strain) was exposed to oxidative stress to select an adapted strain (aero-strain). Conventional NIH Swiss mice were split in two experimental groups which were challenged intraperitoneally with wt-strain and aero-strain, respectively, and a control group, unchallenged. Histopathological and hyperemia analysis were performed by day 30 after infection. Gram stain of aero-strain showed drastic changes in cellular morphology when compared to wt-strain. A significant increase of liver weight/body weight ratio (P < 0.05) as well as a tendency (P = 0.16) to higher spleen weight/body weight ratio were observed for the mice challenged with aero-strain when compared to the two other animal groups. Additionally, these animals also showed hyperemia in the spleen and liver as well as an increased number of inflammatory cells and steatosis in the liver. The results showed that, in addition to extensive changes in cell morphology, the adaptation to oxidative stress might also influence the pathogenicity of F. nucleatum. These findings have clinical implications since in the host tissues this indigenous putative pathogen is exposed to more or less oxygenated environments found on the different anatomic sites invaded by the bacterium.
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Affiliation(s)
- Vania L Silva
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Caixa Postal 486, 30.161-970 Belo Horizonte, MG, Brazil
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Holt SC, Ebersole JL. Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia: the "red complex", a prototype polybacterial pathogenic consortium in periodontitis. Periodontol 2000 2005; 38:72-122. [PMID: 15853938 DOI: 10.1111/j.1600-0757.2005.00113.x] [Citation(s) in RCA: 629] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Stanley C Holt
- Department of Periodontology, The Forsyth Institute, Boston, MA, USA
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24
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Bair-Merritt MH, Shah SS, Zaoutis TE, Bell LM, Feudtner C. Suppurative intracranial complications of sinusitis in previously healthy children. Pediatr Infect Dis J 2005; 24:384-6. [PMID: 15818306 DOI: 10.1097/01.inf.0000160589.40857.ad] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In this retrospective case series, we describe the clinical features and microbiology of 16 previously healthy children with suppurative intracranial complications of sinusitis. Most cases were male adolescents who presented with vomiting in addition to typical sinusitis symptoms. Neurologic signs were often absent. Streptococcus milleri group organisms, along with anaerobes, were common pathogens.
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Affiliation(s)
- Megan H Bair-Merritt
- Pediatric Generalist Research Group, Division of General Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
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25
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Abstract
Although polymicrobial diseases are not a new concept for microbiologists, they are experiencing a resurgence of interest owing to the development of suitable animal models and new molecular techniques that allow these diseases to be studied effectively. This broad review provides an excellent introduction to this fascinating topic. Examples are included of each type of polymicrobial disease and the animal models that are used to study these diseases are discussed. In many instances, schematics for the animal model are presented. Viral co-infections including bovine viral diarrhoeal viruses, porcine reproductive and respiratory syndrome, mixed hepatitis virus infections and HIV co-infection with hepatitis virus are discussed, together with attempts to model these diseases in animals. Viral and bacterial co-infections are reviewed with a special focus on otitis media and the rodent models that have been used to probe this important childhood illness. Of the polybacterial diseases, periodontitis is one of the best understood and a clinically relevant rodent model is now available. This model, and the role of biofilm formation in periodontitis are examined. Fungal infections of humans are often referred to as 'opportunistic' but in fact these infections are often fungal co-infections with viruses such as HIV and fungal mixed co-infections. The roles of these infections in disease and the rodent models used to study them are discussed. Parasite co-infections are thought to have a role in the severity of malaria and the severity of Lyme arthritis. These diseases and attempts to model them are evaluated. Finally, co-infections that are associated with virus-induced immunosuppression are discussed, together with their animal models.
Polymicrobial diseases involve two or more microorganisms that act synergistically, or in succession, to mediate complex disease processes. Although polymicrobial diseases in animals and humans can be caused by similar organisms, these diseases are often also caused by organisms from different kingdoms, genera, species, strains, substrains and even by phenotypic variants of a single species. Animal models are often required to understand the mechanisms of pathogenesis, and to develop therapies and prevention regimes. However, reproducing polymicrobial diseases of humans in animal hosts presents significant challenges.
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Affiliation(s)
- Lauren O Bakaletz
- Center for Microbial Pathogenesis, Columbus Children's Research Institute, Department of Pediatrics, The Ohio State University College of Medicine & Public Health, 700 Children's Drive, Columbus, Ohio 43205-2696, USA.
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Araki H, Kuriyama T, Nakagawa K, Karasawa T. The microbial synergy of Peptostreptococcus micros and Prevotella intermedia in a murine abscess model. ACTA ACUST UNITED AC 2004; 19:177-81. [PMID: 15107069 DOI: 10.1111/j.0902-0055.2004.00138.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This study characterized the microbial interaction of Peptostreptococcus micros and Prevotella intermedia, the major pathogens of dentoalveolar infection, using a murine model. Subcutaneous injection of P. micros cells in the dorsum of the mouse together with living cells of P. intermedia resulted in a significantly larger abscess when compared with single injection of the organisms (P < 0.02). The abscess size was also significantly increased (P < 0.05) when the plate-cultured cell suspension of P. micros was injected into mouse with the culture filtrate of P. intermedia. The heat-treated culture filtrate of P. intermedia also enhanced the virulence of P. micros. P. micros culture filtrate did not affect the virulence of P. intermedia. Interestingly, the virulence of P. micros appeared to be enhanced even when the culture filtrate of P. intermedia was injected at separate sites in the mouse. These results suggest that a heat-stable product or products of P. intermedia increase the virulence of P. micros indirectly by altering the host condition, whereas living cells of P. micros can directly enhance virulence of P. intermedia.
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Affiliation(s)
- H Araki
- Department of Oral and Maxillofacial Surgery, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
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27
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Affiliation(s)
- Gunnar Dahlén
- Department of Oral Microbiology, Göteborg University, Sweden
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