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European Journal of Case Reports in... 2022Infective endocarditis is a condition associated with high morbidity and mortality, usually with univalvular involvement. We describe the case of a 76-year-old woman...
UNLABELLED
Infective endocarditis is a condition associated with high morbidity and mortality, usually with univalvular involvement. We describe the case of a 76-year-old woman with triple-valve endocarditis due to , complicated by perivalvular suppurative lesions, acute heart failure and acute kidney injury. Unfortunately, the patient died despite antibiotic therapy and emergent surgery. This case highlights uncommon triple-valve involvement in the absence of risk factors, posing a diagnostic and therapeutic challenge.
LEARNING POINTS
Native triple-valve endocarditis is extremely rare, especially in the absence of predisposing conditions. has been associated with endocarditis as well colonic and hepatobiliary pathology, so gastrointestinal endoscopy is important as bacteraemia frequently precedes gastrointestinal symptoms, allowing prompt diagnosis.In multivalvular involvement, early surgery is often required, and timely recognition and treatment before complications develop may be decisive for prognosis.
PubMed: 35520359
DOI: 10.12890/2022_003350 -
Journal of Clinical Microbiology Jul 2014Streptococcus gallolyticus subsp. gallolyticus (formerly known as S. bovis biotype I) is a commensal of the gastrointestinal tract in animals and in up to 15% of healthy...
Streptococcus gallolyticus subsp. gallolyticus (formerly known as S. bovis biotype I) is a commensal of the gastrointestinal tract in animals and in up to 15% of healthy humans. Furthermore, it is a facultative pathogen that can cause infectious endocarditis, mastitis, and septicemia. The number of infections is increasing, but the transmission routes and zoonotic potential remain unknown. To assess the zoonotic potential and characterize the epidemiological structure of S. gallolyticus subsp. gallolyticus, we established a multilocus sequence typing (MLST) scheme. We amplified and sequenced internal fragments of seven housekeeping genes. The resulting sequences were analyzed with BioNumerics software 6.6 by using the unweighted-pair group method using average linkages algorithm. A total of 101 S. gallolyticus subsp. gallolyticus strains isolated from animals, humans, and environmental samples were analyzed and divided into 50 sequence types. Our first results highlight the importance of this MLST scheme for investigating the epidemiology, transmission patterns, and infection chains of S. gallolyticus subsp. gallolyticus.
Topics: Animals; Bacterial Proteins; Cluster Analysis; Genes, Essential; Genotype; Humans; Molecular Epidemiology; Multilocus Sequence Typing; Streptococcal Infections; Streptococcus
PubMed: 24789199
DOI: 10.1128/JCM.03329-13 -
BMC Microbiology Mar 2010Streptococcus gallolyticus subsp. gallolyticus is an important causative agent of infective endocarditis (IE) but the knowledge on virulence factors is limited and the...
BACKGROUND
Streptococcus gallolyticus subsp. gallolyticus is an important causative agent of infective endocarditis (IE) but the knowledge on virulence factors is limited and the pathogenesis of the infection is poorly understood. In the present study, we established an experimental in vitro IE cell culture model using EA.hy926 and HUVEC cells to investigate the adhesion and invasion characteristics of 23 Streptococcus gallolyticus subsp. gallolyticus strains from different origins (human IE-derived isolates, other human clinical isolates, animal isolates). Adhesion to eight components of the extracellular matrix (ECM) and the ability to form biofilms in vitro was examined in order to reveal features of S. gallolyticus subsp. gallolyticus endothelial infection. In addition, the strains were analyzed for the presence of the three virulence factors gtf, pilB, and fimB by PCR.
RESULTS
The adherence to and invasion characteristics of the examined S. gallolyticus subsp. gallolyticus strains to the endothelial cell line EA.hy926 differ significantly among themselves. In contrast, the usage of three different in vitro models (EA.hy926 cells, primary endothelial cells (HUVECs), mechanical stretched cells) revealed no differences regarding the adherence to and invasion characteristics of different strains. Adherence to the ECM proteins collagen I, II and IV revealed the highest values, followed by fibrinogen, tenascin and laminin. Moreover, a strong correlation was observed in binding to these proteins by the analyzed strains. All strains show the capability to adhere to polystyrole surfaces and form biofilms. We further confirmed the presence of the genes of two known virulence factors (fimB: all strains, gtf: 19 of 23 strains) and demonstrated the presence of the gene of one new putative virulence factor (pilB: 9 of 23 strains) by PCR.
CONCLUSION
Our study provides the first description of S. gallolyticus subsp. gallolyticus adhesion and invasion of human endothelial cells, revealing important initial information of strain variability, behaviour and characteristics of this as yet barely analyzed pathogen.
Topics: Analysis of Variance; Bacterial Adhesion; Bacterial Proteins; Biofilms; Cell Line, Transformed; Colony Count, Microbial; Endocarditis, Bacterial; Endothelial Cells; Extracellular Matrix Proteins; Host-Pathogen Interactions; Humans; Statistics, Nonparametric; Streptococcal Infections; Streptococcus; Virulence
PubMed: 20233397
DOI: 10.1186/1471-2180-10-78 -
Clinical Microbiology and Infection :... Dec 2015We describe the incidence and patient characteristics of Streptococcus gallolyticus meningitis. We identified S. gallolyticus meningitis in a nationwide cohort of... (Meta-Analysis)
Meta-Analysis Review
We describe the incidence and patient characteristics of Streptococcus gallolyticus meningitis. We identified S. gallolyticus meningitis in a nationwide cohort of patients with community-acquired bacterial meningitis, and performed a systematic review and meta-analysis of all reported adult cases in the literature. Five cases were identified (0.3%) in a cohort of 1561 episodes of bacterial meningitis. In one patient, bowel disease (colon polyps) was identified as a predisposing condition for S. gallolyticus infection, whereas no patients were diagnosed with endocarditis. In a combined analysis of our patients and 37 reported in the literature, we found that the median age was 59 years. Predisposing factors were present in 21 of 42 patients (50%), and mainly consisted of immunosuppressive therapy (seven patients), cancer (four patients), and alcoholism (four patients). Colon disease was identified in 15 of 24 patients (63%) and endocarditis in five of 27 patients (18%). Co-infection with Strongyloides stercoralis was identified in 14 of 34 patients (41%), ten of whom were infected with human immunodeficiency virus or human T-lymphotropic virus. Outcomes were described for 37 patients; eight died (22%) and one (3%) had neurological sequelae. S. gallolyticus is an uncommon cause of bacterial meningitis, with specific predisposing conditions. When it is identified, consultation with a cardiologist and gastroenterologist is warranted to rule out underlying endocarditis or colon disease. Stool examinations for Strongyloides stercoralis should be performed in patients who have travelled to or originate from endemic areas.
Topics: Aged; Aged, 80 and over; Community-Acquired Infections; Feces; Female; Humans; Incidence; Male; Meningitis, Bacterial; Middle Aged; Observational Studies as Topic; Prospective Studies; Risk Factors; Streptococcal Infections; Streptococcus
PubMed: 26314916
DOI: 10.1016/j.cmi.2015.08.003 -
Digestive Diseases and Sciences Aug 2023Streptococcus gallolyticus subspecies gallolyticus (SGG) and Fusobacterium (F.) nucleatum have been implicated in colorectal carcinogenesis. Here, the association of...
BACKGROUND
Streptococcus gallolyticus subspecies gallolyticus (SGG) and Fusobacterium (F.) nucleatum have been implicated in colorectal carcinogenesis. Here, the association of immune responses to bacterial exposure with advancing stages of colorectal neoplasia was assessed by multiplex serology.
METHODS
Immunoglobulin (Ig) A and G antibody responses to eleven proteins each of F. nucleatum and SGG were measured in plasma of controls (n = 100) and patients with colorectal cancer (CRC, n = 25), advanced adenoma (n = 82), or small polyps (n = 85). Multivariable logistic regression was used to evaluate the association of bacterial sero-positivity with colorectal neoplasia. In a cohort subset with matched data (n = 45), F. nucleatum sero-positivity was correlated with bacterial abundance in both neoplastic and matched normal tissue.
RESULTS
IgG sero-positivity to Fn1426 of F. nucleatum was associated with an increased CRC risk (OR = 4.84; 95% CI 1.46-16.0), while IgA sero-positivity to any SGG protein or specifically Gallo0272 and Gallo1675 alone was associated with increased advanced adenoma occurrence (OR = 2.02, 95% CI 1.10-3.71; OR = 2.67, 95% CI 1.10-6.46; and OR = 6.17, 95% CI 1.61-23.5, respectively). Only F. nucleatum abundance in the normal mucosa positively correlated with the IgA response to the Fn1426 antigen (Correlation coefficient (r) = 0.38, p < 0.01).
CONCLUSION
Antibody responses to SGG and F. nucleatum were associated with occurrence of colorectal adenomas and CRC, respectively. Further studies are needed to clarify the role these microbes or the immune response to their antigens may have in colorectal carcinogenesis stages.
Topics: Humans; Fusobacterium nucleatum; Streptococcus gallolyticus; Antibody Formation; Colorectal Neoplasms; Bacteria; Adenoma; Carcinogenesis; Fusobacterium Infections
PubMed: 37338617
DOI: 10.1007/s10620-023-08001-4 -
PLoS Pathogens Jan 2021Streptococcus gallolyticus subspecies gallolyticus (Sgg) has a strong clinical association with colorectal cancer (CRC) and actively promotes the development of colon...
Streptococcus gallolyticus subspecies gallolyticus (Sgg) has a strong clinical association with colorectal cancer (CRC) and actively promotes the development of colon tumors. However, the molecular determinants involved in Sgg pathogenicity in the gut are unknown. Bacterial type VII secretion systems (T7SS) mediate pathogen interactions with their host and are important for virulence in pathogenic mycobacteria and Staphylococcus aureus. Through genome analysis, we identified a locus in Sgg strain TX20005 that encodes a putative type VII secretion system (designated as SggT7SST05). We showed that core genes within the SggT7SST05 locus are expressed in vitro and in the colon of mice. Western blot analysis showed that SggEsxA, a protein predicted to be a T7SS secretion substrate, is detected in the bacterial culture supernatant, indicating that this SggT7SST05 is functional. Deletion of SggT7SST05 (TX20005Δesx) resulted in impaired bacterial adherence to HT29 cells and abolished the ability of Sgg to stimulate HT29 cell proliferation. Analysis of bacterial culture supernatants suggest that SggT7SST05-secreted factors are responsible for the pro-proliferative activity of Sgg, whereas Sgg adherence to host cells requires both SggT7SST05-secreted and bacterial surface-associated factors. In a murine gut colonization model, TX20005Δesx showed significantly reduced colonization compared to the parent strain. Furthermore, in a mouse model of CRC, mice exposed to TX20005 had a significantly higher tumor burden compared to saline-treated mice, whereas those exposed to TX20005Δesx did not. Examination of the Sgg load in the colon in the CRC model suggests that SggT7SST05-mediated activities are directly involved in the promotion of colon tumors. Taken together, these results reveal SggT7SST05 as a previously unrecognized pathogenicity determinant for Sgg colonization of the colon and promotion of colon tumors.
Topics: Animals; Cell Proliferation; Colonic Neoplasms; Gastrointestinal Microbiome; Gastrointestinal Tract; Humans; Mice; Mice, Inbred A; Streptococcal Infections; Streptococcus gallolyticus subspecies gallolyticus; Type VII Secretion Systems
PubMed: 33406160
DOI: 10.1371/journal.ppat.1009182 -
Indian Journal of Critical Care... Oct 2020is an important cause of bacteremia and infective endocarditis in adults. Studies from other parts of the world have shown a strong association between bacteremia and...
INTRODUCTION
is an important cause of bacteremia and infective endocarditis in adults. Studies from other parts of the world have shown a strong association between bacteremia and colonic neoplasia. The profile of bacteremia is understudied in Indian population.
MATERIALS AND METHODS
We retrospectively analyzed the data of 16 patients with bacteremia obtained from microbiology registry. BacT/ALERT positive samples were inoculated into blood agar, chocolate agar, and MacConkey agar. Organisms were identified by the VITEK 2 microbial identification system, and susceptibility was done by the microbroth dilution method as per Clinical and Laboratory Standards Institute (CLSI) M100 guidelines. Clinical details were obtained from electronic medical records.
RESULTS
Majority of our isolates were subspecies . Total 16 patients had isolated from blood over a 1 year period. The median age was 58 years (IQR: 46.5-66). Eleven were males; type II diabetes mellitus and chronic liver disease were the common comorbidities observed in our patients. None of our patients had underlying infective endocarditis or colonic malignancy. Penicillin sensitivity was 81.2% while all the isolates were susceptible to ceftriaxone. Ampicillin resistance was seen in only one of the isolates. In-hospital mortality was 12.5%.
CONCLUSION
subsp. is the commonest subspecies of isolated in our population. Unlike previous studies, colonic neoplasia and infective endocarditis were rare in our patients. Type II diabetes mellitus and chronic liver disease were the commonest risk factors identified in patients with bacteremia.
HOW TO CITE THIS ARTICLE
Niyas VKM, Arjun R, Sasidharan A, Palakunnath GA. Bacteremia: An Experience from a Tertiary Center in South India. Indian J Crit Care Med 2020;24(10):943-945.
PubMed: 33281319
DOI: 10.5005/jp-journals-10071-23569 -
Journal of Bacteriology Mar 2019Cyclic di-AMP is a recently identified second messenger exploited by a number of Gram-positive bacteria to regulate important biological processes. Here, we studied the...
Increased Intracellular Cyclic di-AMP Levels Sensitize Streptococcus gallolyticus subsp. gallolyticus to Osmotic Stress and Reduce Biofilm Formation and Adherence on Intestinal Cells.
Cyclic di-AMP is a recently identified second messenger exploited by a number of Gram-positive bacteria to regulate important biological processes. Here, we studied the phenotypic alterations induced by the increased intracellular c-di-AMP levels in , an opportunistic pathogen responsible for septicemia and endocarditis in the elderly. We report that an c-di-AMP phosphodiesterase knockout mutant, which displays a 1.5-fold higher intracellular c-di-AMP levels than the parental strain UCN34, is more sensitive to osmotic stress and is morphologically smaller than the parental strain. Unexpectedly, we found that a higher level of c-di-AMP reduced biofilm formation of on abiotic surfaces and reduced adherence and cell aggregation on human intestinal cells. A genome-wide transcriptomic analysis indicated that c-di-AMP regulates many biological processes in , including the expression of various ABC transporters and disease-associated genes encoding bacteriocin and Pil3 pilus. Complementation of the in-frame deletion mutant with a plasmid carrying in from its native promoter restored bacterial morphology, tolerance to osmotic stress, biofilm formation, adherence to intestinal cells, bacteriocin production, and Pil3 pilus expression. Our results indicate that c-di-AMP is a pleiotropic signaling molecule in that may be important for pathogenesis. is an opportunistic pathogen responsible for septicemia and endocarditis in the elderly and is also strongly associated with colorectal cancer. can form biofilms, express specific pili to colonize the host tissues, and produce a specific bacteriocin allowing killing of commensal bacteria in the murine colon. Nevertheless, how the expression of these colonization factors is regulated remains largely unknown. Here, we show that c-di-AMP plays pleiotropic roles in , controlling the tolerance to osmotic stress, cell size, biofilm formation on abiotic surfaces, adherence and cell aggregation on human intestinal cells, expression of Pil3 pilus, and production of bacteriocin. This study indicates that c-di-AMP may constitute a key regulatory molecule for host colonization and pathogenesis.
Topics: 3',5'-Cyclic-AMP Phosphodiesterases; Animals; Bacterial Adhesion; Biofilms; Cell Line; Cytosol; Dinucleoside Phosphates; Epithelial Cells; Gene Deletion; Gene Expression Profiling; Gene Expression Regulation, Bacterial; Genetic Complementation Test; Humans; Mice; Osmotic Pressure; Streptococcus gallolyticus subspecies gallolyticus
PubMed: 30617242
DOI: 10.1128/JB.00597-18 -
Journal of Microbiology, Immunology,... Jun 2023Streptococcus gallolyticus subsp. pasteurianus (SGSP) is a commensal in the intestinal tract and a potential pathogen of neonatal sepsis. During an 11-month period, four...
BACKGROUND
Streptococcus gallolyticus subsp. pasteurianus (SGSP) is a commensal in the intestinal tract and a potential pathogen of neonatal sepsis. During an 11-month period, four consecutive cases of SGSP sepsis were identified in one postnatal care unit (unit A) without evidence of vertical transmission. Therefore, we initiated this study to investigate the reservoir and mode of transmission of SGSP.
METHOD
We performed cultures of stool samples from healthcare workers in unit A and unit B (another unit without SGSP sepsis). If SGSP was positive in feces, we performed isolate pulsotyping and genotyping by using pulsed-field gel electrophoresis (PFGE) and analyzing random amplified polymorphic DNA (RAPD) patterns, respectively.
RESULTS
Five staff members in unit A showed positivity for SGSP. All samples from unit B were negative. We identified two major pulsogroups (groups C and D) by PFGE. In group D, the strains isolated from 3 consecutive sepsis patients (P1, P2 and P3) were closely related and clustered together as those from 2 staff members (C1/C2, C6). One staff (staff 4) had a direct contact history with patient (P1) confirmed to have the same clone. The last isolate of the patient in our study (P4) belonged to a distinct clone.
CONCLUSION
We found prolonged gut colonization of SGSP in healthcare workers and its epidemiological relatedness to neonatal sepsis. Fecal-oral or contact transmission is a possible route of SGSP infection. Fecal shedding among staff may be associated with neonatal sepsis in healthcare facilities.
Topics: Infant, Newborn; Humans; Streptococcus gallolyticus; Neonatal Sepsis; Streptococcal Infections; Random Amplified Polymorphic DNA Technique; Sepsis
PubMed: 36870812
DOI: 10.1016/j.jmii.2023.02.004 -
Microbiology Spectrum Aug 2023This study aimed to identify which streptococcal species are closely associated with infective endocarditis (IE) and to evaluate risk factors for mortality in patients...
This study aimed to identify which streptococcal species are closely associated with infective endocarditis (IE) and to evaluate risk factors for mortality in patients with streptococcal IE. We performed a retrospective cohort study of all patients with streptococcal bloodstream infection (BSI) from January 2010 to June 2020 in a tertiary hospital in South Korea. We compared clinical and microbiological characteristics of streptococcal BSIs according to the diagnosis of IE. We performed multivariate analysis to evaluate the risk of IE according to streptococcal species and risk factors for mortality in streptococcal IE. A total of 2,737 patients were identified during the study period, and 174 (6.4%) were diagnosed with IE. The highest IE prevalence was in patients with Streptococcus mutans BSI (33% [9/27]) followed by S. sanguinis (31% [20/64]), S. gordonii (23% [5/22]), S. gallolyticus (16% [12/77]), and S. oralis (12% [14/115]). In multivariate analysis, previous IE, high-grade BSI, native valve disease, prosthetic valve, congenital heart disease, and community-onset BSI were independent risk factors for IE. After adjusting for these factors, S. sanguinis (adjusted OR [aOR], 7.75), S. mutans (aOR, 5.50), and S. gallolyticus (aOR, 2.57) were significantly associated with higher risk of IE, whereas S. pneumoniae (aOR, 0.23) and (aOR, 0.37) were associated with lower risk of IE. Age, hospital-acquired BSI, ischemic heart disease, and chronic kidney disease were independent risk factors for mortality in streptococcal IE. Our study points to significant differences in the prevalence of IE in streptococcal BSI according to species. Our study of risk of infective endocarditis in patients with streptococcal bloodstream infection demonstrated that Streptococcus sanguinis, S. mutans, and S. gallolyticus were significantly associated with higher risk of infective endocarditis. However, when we evaluated the performance of echocardiography in patients with streptococcal bloodstream infection, patients with S. mutans and S. gordonii bloodstream infection had a tendency of low performance in echocardiography. There are significant differences in the prevalence of infective endocarditis in streptococcal bloodstream infection according to species. Therefore, performing echocardiography in streptococcal bloodstream infection with a high prevalence of, and significant association with, infective endocarditis is desirable.
Topics: Humans; Retrospective Studies; Streptococcus; Endocarditis, Bacterial; Endocarditis; Streptococcal Infections; Sepsis
PubMed: 37284757
DOI: 10.1128/spectrum.01049-23