-
Revista Argentina de Microbiologia 2022The aim of this review is to present an update on the susceptibility of viridans group streptococci (VGS) to β-lactam antimicrobials, with emphasis on the Argentinean... (Review)
Review
The aim of this review is to present an update on the susceptibility of viridans group streptococci (VGS) to β-lactam antimicrobials, with emphasis on the Argentinean scenario. VGS are a heterogeneous group including five groups of species, each one exhibiting peculiar susceptibility patterns to penicillin (PEN). Species of the Streptococcus mitis group are frequently nonsusceptible to PEN. PEN resistance is associated with changes in PEN-binding proteins. In Argentina, one to two thirds of VGS are nonsusceptible to PEN. Third generation cephalosporins and carbapenems are currently more effective in vitro than PEN against VGS. Mortality was associated to nonsusceptibility to PEN in at least two studies involving patients with bacteremia caused by VGS. Treatment of endocarditis due to VGS should be adjusted/to the PEN susceptibility of the isolates. Vancomycin may be an alternative choice for treating endocarditis caused by PEN-resistant isolates (MIC≥4μg/ml).
Topics: Humans; Microbial Sensitivity Tests; Streptococcal Infections; Viridans Streptococci; Penicillins; Monobactams; beta-Lactams; Anti-Bacterial Agents; Endocarditis
PubMed: 36266147
DOI: 10.1016/j.ram.2022.06.004 -
Circulation May 2021In 2007, the American Heart Association published updated evidence-based guidelines on the recommended use of antibiotic prophylaxis to prevent viridans group... (Review)
Review
BACKGROUND
In 2007, the American Heart Association published updated evidence-based guidelines on the recommended use of antibiotic prophylaxis to prevent viridans group streptococcal (VGS) infective endocarditis (IE) in cardiac patients undergoing invasive procedures. The 2007 guidelines significantly scaled back the underlying conditions for which antibiotic prophylaxis was recommended, leaving only 4 categories thought to confer the highest risk of adverse outcome. The purpose of this update is to examine interval evidence of the acceptance and impact of the 2007 recommendations on VGS IE and, if needed, to make revisions based on this evidence.
METHODS AND RESULTS
A writing group was formed consisting of experts in prevention and treatment of infective endocarditis including members of the American Dental Association, the Infectious Diseases Society of America, and the American Academy of Pediatrics, in addition to the American Heart Association. MEDLINE database searches were done for English language articles on compliance with the recommendations in the 2007 guidelines and the frequency of and morbidity or mortality from VGS IE after publication of the 2007 guidelines. Overall, there was good general awareness of the 2007 guidelines but variable compliance with recommendations. There was no convincing evidence that VGS IE frequency, morbidity, or mortality has increased since 2007.
CONCLUSIONS
On the basis of a review of the available evidence, there are no recommended changes to the 2007 VGS IE prevention guidelines. We continue to recommend VGS IE prophylaxis only for categories of patients at highest risk for adverse outcome while emphasizing the critical role of good oral health and regular access to dental care for all. Randomized controlled studies to determine whether antibiotic prophylaxis is effective against VGS IE are needed to further refine recommendations.
Topics: American Heart Association; Endocarditis; Humans; United States; Viridans Streptococci
PubMed: 33853363
DOI: 10.1161/CIR.0000000000000969 -
Monographs in Oral Science 2021Dental biofilms can cause major oral diseases like gingivitis, periodontitis, and caries. Orthodontic appliances promote supra- and subgingival biofilm accumulation,... (Review)
Review
Dental biofilms can cause major oral diseases like gingivitis, periodontitis, and caries. Orthodontic appliances promote supra- and subgingival biofilm accumulation, alter the oral microbiome, and hamper oral hygiene. Orthodontic treatment can be associated with adverse effects, such as enamel decalcification, gingivitis, and periodontal disease. The aim of this review is to summarize the changes in supra- and subgingival biofilm and periodontal tissues during and after orthodontic treatment. Studies have reported elevated levels of Streptococcus mutans and periodontopathogenic bacteria in patients undergoing orthodontic treatment. In general, the microbial changes and periodontal parameters decreased to pretreatment levels after appliance removal. Nevertheless, some adverse effects associated with orthodontic treatment are not reversible, such as enamel decalcifications caused by metabolic products of high levels of cariogenic bacteria. The evidence suggests that the roughness and constituents of the orthodontic materials influence the bacterial colonization. Therefore, several antibacterial orthodontic bonding systems, which show antibacterial effects in vitro, have been developed. The importance of adequate oral hygiene should be emphasized to all orthodontic patients. They should be frequently reminded and motivated to obtain a good oral hygiene. The evidence from the current literature suggests the safest way for orthodontic treatment in periodontally diseased patients may be after successful completion of the periodontal therapy. However, the exact time point needs to be better clarified in future studies.
Topics: Biofilms; Dental Caries; Gingivitis; Humans; Orthodontic Appliances; Streptococcus mutans
PubMed: 33427218
DOI: 10.1159/000510193 -
Critical Reviews in Microbiology Sep 2021Dental caries is one of the most prevalent and costly biofilm-associated infectious diseases affecting most of the world's population. In particular, dental caries is... (Review)
Review
Dental caries is one of the most prevalent and costly biofilm-associated infectious diseases affecting most of the world's population. In particular, dental caries is driven by dysbiosis of the dental biofilm adherent to the enamel surface. Specific types of acid-producing bacteria, especially , colonize the dental surface and cause damage to the hard tooth structure in the presence of fermentable carbohydrates. has been established as the major cariogenic pathogen responsible for human dental caries, with a high ability to form biofilms. The exopolysaccharide (EPS) matrix, mainly contributed by , has been considered as a virulence determinant of cariogenic biofilm. As EPS is an important virulence factor, targeting EPS metabolism could be useful in preventing cariogenic biofilm formation. This review summarizes plausible strategies targeting biofilms by degrading EPS structure, inhibiting EPS production, and disturbing the EPS metabolism-related gene expression and regulatory systems.
Topics: Animals; Biofilms; Dental Caries; Gene Expression Regulation, Bacterial; Humans; Polysaccharides, Bacterial; Prebiotics; Probiotics; Streptococcus mutans; Virulence; Virulence Factors
PubMed: 33938347
DOI: 10.1080/1040841X.2021.1915959 -
Monographs in Oral Science 2021In reality, most microorganisms are not free floating. They exist in biofilms, a community of many of them from the same species or from other genera and attached to... (Review)
Review
In reality, most microorganisms are not free floating. They exist in biofilms, a community of many of them from the same species or from other genera and attached to surfaces.Microorganisms undergo a transition from free-floating, planktonic microorganisms to a sessile, surface-attached one. Contact with a surface induces changes in gene expression, and a strong attachment of microcolonies occurs only after a few hours. The maturation of a biofilm is associated with matrix formation. The matrix is of importance as it provides stability and protects against environmental insults, it consists of polysaccharides, water, lipids, proteins, and extracellular DNA. Biofilms can be found everywhere - in the environment, in water systems - and they play an important role in medicine and dentistry. In medicine, infections of chronic wounds, of the respiratory tract in cystic fibrosis infections, or when linked with incorporated biomaterial are mostly biofilm associated. In the oral cavity, the most prevalent oral diseases, dental caries, and periodontitis are multi-species biofilm-associated diseases. Although not acting alone, key pathogens drive the development of the microbial shift. Microorganisms metabolize sugar and create an acidic environment where aciduric bacteria (including mutans streptococci) become dominant, which leads to the demineralization of enamel and dentine. Porphyromonas gingivaliscauses biofilm dysbiosis in the development of periodontal disease. Biofilm-associated infections are extremely difficult to treat. The matrix serves as a barrier to antimicrobial agents and there are subpopulations of dormant bacteria resistant to antimicrobials requiring metabolically active cells. Approaches to treat biofilm-associated infections include the modification of the biofilm composition, inhibitors of quorum-sensing molecules, or interfering with matrix constituents.
Topics: Biofilms; Dental Caries; Humans; Mouth; Quorum Sensing; Streptococcus mutans
PubMed: 33427230
DOI: 10.1159/000510184 -
Gastroenterology Jun 2022Most patients with gastric cancer (GCa) are diagnosed at an advanced stage. We aimed to investigate novel fecal signatures for clinical application in early diagnosis of... (Observational Study)
Observational Study
BACKGROUND & AIMS
Most patients with gastric cancer (GCa) are diagnosed at an advanced stage. We aimed to investigate novel fecal signatures for clinical application in early diagnosis of GCa.
METHODS
This was an observational study that included 1043 patients from 10 hospitals in China. In the discovery cohort, 16S ribosomal RNA gene analysis was performed in paired samples (tissues and feces) from patients with GCa and chronic gastritis (ChG) to determine differential abundant microbes. Their relative abundances were detected using quantitative real-time polymerase chain reaction to test them as bacterial candidates in the training cohort. Their diagnostic efficacy was validated in the validation cohort.
RESULTS
Significant enrichments of Streptococcus anginosus (Sa) and Streptococcus constellatus (Sc) in GCa tumor tissues (P < .05) and feces (P < .0001) were observed in patients with intraepithelial neoplasia, early and advanced GCa. Either the signature parallel test Sa∪Sc or single signature Sa/Sc demonstrated superior sensitivity (Sa: 75.6% vs 72.1%, P < .05; Sc: 84.4% vs 64.0%, P < .001; and Sa∪Sc: 91.1% vs 81.4%, P < .01) in detecting early GCa compared with advanced GCa (specificity: Sa: 84.0% vs 83.9%, Sc: 70.4% vs 82.3%, and Sa∪Sc: 64.0% vs 73.4%). Fecal signature Sa∪Sc outperformed Sa∪CEA/Sc∪CEA in the discrimination of advanced GCa (sensitivity: 81.4% vs 74.2% and 81.4% vs 72.3%, P < .01; specificity: 73.4% vs 81.0 % and 73.4% vs 81.0%). The performance of Sa∪Sc in the diagnosis of both early and advanced GCa was verified in the validation cohort.
CONCLUSION
Fecal Sa and Sc are noninvasive, accurate, and sensitive signatures for early warning in GCa. (ClinicalTrials.gov, Number: NCT04638959).
Topics: Early Detection of Cancer; Feces; Humans; Stomach Neoplasms; Streptococcus anginosus; Streptococcus constellatus
PubMed: 35167866
DOI: 10.1053/j.gastro.2022.02.015 -
Periodontology 2000 Feb 2021Interspecies interactions are key determinants in biofilm behavior, ecology, and architecture. The cellular responses of microorganisms to each other at transcriptional,... (Review)
Review
Interspecies interactions are key determinants in biofilm behavior, ecology, and architecture. The cellular responses of microorganisms to each other at transcriptional, proteomic, and metabolomic levels ultimately determine the characteristics of biofilm and the corresponding implications for health and disease. Advances in omics technologies have revolutionized our understanding of microbial community composition and their activities as a whole. Large-scale analyses of the complex interaction between the many microbial species residing within a biofilm, however, are currently still hampered by technical and bioinformatics challenges. Thus, studies of interspecies interactions have largely focused on the transcriptional and proteomic changes that occur during the contact of a few prominent species, such as Porphyromonas gingivalis, Streptococcus mutans, Candida albicans, and a few others, with selected partner species. Expansion of available tools is necessary to grow the revealing, albeit limited, insight these studies have provided into a profound understanding of the nature of individual microbial responses to the presence of others. This will allow us to answer important questions including: Which intermicrobial interactions orchestrate the myriad of cooperative, synergistic, antagonistic, manipulative, and other types of relationships and activities in the complex biofilm environment, and what are the implications for oral health and disease?
Topics: Biofilms; Candida albicans; Humans; Porphyromonas gingivalis; Proteomics; Streptococcus mutans
PubMed: 33226675
DOI: 10.1111/prd.12354 -
Science Signaling Sep 2023In eukaryotes, lactate produced during glycolysis is involved in regulating multiple metabolic processes through lysine lactylation (Kla). To explore the potential link... (Review)
Review
In eukaryotes, lactate produced during glycolysis is involved in regulating multiple metabolic processes through lysine lactylation (Kla). To explore the potential link between metabolism and Kla in prokaryotes, we investigated the distribution of Kla in the cariogenic bacterium during planktonic growth in low-sugar conditions and in biofilm-promoting, high-sugar conditions. We identified 1869 Kla sites in 469 proteins under these two conditions, with the biofilm growth state showing a greater number of lactylated sites and proteins. Although high sugar increased Kla globally, it reduced lactylation of RNA polymerase subunit α (RpoA) at Lys. Lactylation at this residue inhibited the synthesis of extracellular polysaccharides, a major constituent of the cariogenic biofilm. The Gcn5-related N-acetyltransferase (GNAT) superfamily enzyme GNAT13 exhibited lysine lactyltransferase activity in cells and lactylated Lys in RpoA in vitro. Either GNAT13 overexpression or lactylation of Lys in RpoA inhibited biofilm formation. These results provide an overview of the distribution and potential functions of Kla and improve our understanding of the role of lactate in the metabolic regulation of prokaryotes.
Topics: Biofilms; Glycolysis; Lactic Acid; Lysine; Streptococcus mutans; Sugars
PubMed: 37669396
DOI: 10.1126/scisignal.adg1849 -
Clinical Infectious Diseases : An... Nov 2023Evidence supporting combination treatment with a beta-lactam plus an aminoglycoside (C-BA) for endocarditis caused by viridans and gallolyticus group streptococci...
BACKGROUND
Evidence supporting combination treatment with a beta-lactam plus an aminoglycoside (C-BA) for endocarditis caused by viridans and gallolyticus group streptococci (VGS-GGS) with intermediate susceptibility to penicillin (PENI-I) is lacking. We assessed the clinical characteristics and outcomes of PEN-I VGS-GGS endocarditis and compared the effectiveness and safety of C-BA with third-generation cephalosporin monotherapy.
METHODS
Retrospective analysis of prospectively collected data of a cohort of definite endocarditis caused by penicillin-susceptible and PENI-I VGS-GGS (penicillin minimum inhibitory concentration ranging from 0.25 to 2 mg/L) between 2008 and 2018 in 40 Spanish hospitals. We compared cases treated with monotherapy or with C-BA and performed multivariable analyses of risk factors for in-hospital and 1-year mortality.
RESULTS
A total of 914 consecutive cases of definite endocarditis caused by VGS-GGS with complete or intermediate susceptibility to penicillin were included. A total of 688 (75.3%) were susceptible to penicillin and 226 (24.7%) were PENI-I. Monotherapy was used in 415 (45.4%) cases (cephalosporin in 331 cases) and 499 (54.6%) cases received C-BA. In-hospital mortality was 11.9%, and 190 (20.9%) patients developed acute kidney injury. Heart failure (odds ratio [OR]: 6.06; 95% confidence interval [CI]: 1.37-26.87; P = .018), central nervous system emboli (OR: 9.83; 95% CI: 2.17-44.49; P = .003) and intracardiac abscess (OR: 13.47; 95% CI: 2.24-81.08; P = .004) were independently associated with in-hospital mortality among PEN-I VGS-GGS cases, while monotherapy was not (OR: 1.01; 95% CI: .26-3.96; P = .982).
CONCLUSIONS
Our findings support the use of cephalosporin monotherapy in PEN-I VGS-GGS endocarditis in order to avoid nephrotoxicity without adversely affecting patient outcomes.
Topics: Humans; Penicillins; Retrospective Studies; Endocarditis, Bacterial; Streptococcal Infections; Anti-Bacterial Agents; Endocarditis; Anti-Infective Agents; Viridans Streptococci; Treatment Outcome; Cephalosporins
PubMed: 37345869
DOI: 10.1093/cid/ciad375 -
Frontiers in Cellular and Infection... 2024Streptococci are primary colonizers of the oral cavity where they are ubiquitously present and an integral part of the commensal oral biofilm microflora. The role oral... (Review)
Review
Streptococci are primary colonizers of the oral cavity where they are ubiquitously present and an integral part of the commensal oral biofilm microflora. The role oral streptococci play in the interaction with the host is ambivalent. On the one hand, they function as gatekeepers of homeostasis and are a prerequisite for the maintenance of oral health - they shape the oral microbiota, modulate the immune system to enable bacterial survival, and antagonize pathogenic species. On the other hand, also recognized pathogens, such as oral and , which trigger the onset of dental caries belong to the genus . In the context of periodontitis, oral streptococci as excellent initial biofilm formers have an accessory function, enabling late biofilm colonizers to inhabit gingival pockets and cause disease. The pathogenic potential of oral streptococci fully unfolds when their dissemination into the bloodstream occurs; streptococcal infection can cause extra-oral diseases, such as infective endocarditis and hemorrhagic stroke. In this review, the taxonomic diversity of oral streptococci, their role and prevalence in the oral cavity and their contribution to oral health and disease will be discussed, focusing on the virulence factors these species employ for interactions at the host interface.
Topics: Humans; Dental Caries; Streptococcus; Streptococcus mutans; Streptococcus sobrinus; Mouth; Biofilms
PubMed: 38456080
DOI: 10.3389/fcimb.2024.1357631