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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 -
Infection and Drug Resistance 2020, formerly known as one of the group, is frequently associated with endocarditis. Current guidelines recommended diagnostic work-up for endocarditis among patients with...
BACKGROUND
, formerly known as one of the group, is frequently associated with endocarditis. Current guidelines recommended diagnostic work-up for endocarditis among patients with bacteremia. However, subsp. , was found to be associated with neonatal sepsis and liver diseases and is less commonly associated with endocarditis compared with subsp. . Our study aimed to identify the risk factors for subsp. endocarditis to help select the patients for echocardiography.
METHODS
In this retrospective cohort study, medical records from all adult patients with subsp. isolated from blood cultures at Phramongkutklao Hospital from 2009 to 2015 were reviewed. Patients who had mixed bacteremia or missing records were excluded from the study.
RESULTS
During the study period, subsp. was isolated among 106 individuals. Mean age was 66.9±15.6 years. Most patients (61.3%) were male, with cirrhosis as the most common underlying diseases (46.2%), followed by malignancy and chronic kidney disease. Most common manifestations included primary bacteremia (44.3%), followed by spontaneous bacterial peritonitis (23.6%). Infective endocarditis was found among 9 patients. No patients with cirrhosis or single blood specimen of bacteremia had endocarditis (RR 0; p-value 0.003, and RR 1.35; p-value 0.079). The common complications associated with endocarditis were acute respiratory failure (RR 4.32; p-value 0.05), whereas acute kidney injury was a protective factor (RR 0; p-value 0.01). Among 76 patients who had records of 2-year follow-up, no new diagnosis of endocarditis or malignancy was observed.
CONCLUSION
Among patients with subsp. bacteremia, echocardiography might not be needed among patients with cirrhosis and without sustained bacteremia.
PubMed: 32765016
DOI: 10.2147/IDR.S265722 -
The Medical Journal of Malaysia May 2023World Health Organization (2019) has declared colorectal cancer (CRC) as the second most common cancer in females and third in males, where the incidence seems to rise...
INTRODUCTION
World Health Organization (2019) has declared colorectal cancer (CRC) as the second most common cancer in females and third in males, where the incidence seems to rise year by year. One of the very few potential pathogens specifically associated with malignant colonic diseases is Streptococcus gallolyticus (Sg). Sg is a part of the intestinal flora which formerly known as biotype I of Streptococcus bovis, belongs to Group D streptococci. Owing to only a few researches done in determining evidence to support Sg as a determinant of CRC, a systematic review is constructed.
MATERIALS AND METHODS
Full-text articles on case-control and cohort studies published from 1st January 2010 to 1st October 2020 were searched using Google Scholar, PubMed and JSTOR. People of all age groups and Sg bacteraemia or colonisation were the type of participant and exposure used for the search strategy, respectively. Data collection was done by three reviewers and checked by two reviewers for discrepancies. All the papers were critically appraised using the STROBE statement. Qualitative synthesis was done by descriptive comparison, distribution of Sg according to stage comparison, method used for Sg detection comparison and risk of bias comparison.
RESULT
Seven out of 11 articles that fulfil the eligibility criteria were selected. Four papers have low overall risk of bias due to low confounding or selection bias. Sg is found to be a risk factor for CRC from three papers studied, whereas the other four papers did not include the strength of association. Only two papers studied the association between the distribution of Sg and stages of CRC, where the results were contradictory from each other, making it to be inconclusive. The most common method used for Sg detection is a culturing technique, followed by molecular and biochemical techniques.
CONCLUSION
There is insufficient evidence to prove the association between Sg bacteraemia as the risk factor for CRC as well as the association between the Sg distribution and stages of CRC. Culturing technique is the most common method used for the detection of bacteria, but it requires subsequent investigations to confirm the presence of Sg. Thus, it is recommended that more studies need to be done using strong statistical analysis to control for most of the confounders with comprehensive explanation and use of more methods in the detection of Sg.
Topics: Male; Female; Humans; Streptococcus gallolyticus; Colorectal Neoplasms; Bacteremia
PubMed: 37271851
DOI: No ID Found -
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 -
Infection and Drug Resistance 2023subspecies , formerly classified as biotype II/2 until 2003, is a rare cause of infant meningitis. Over the past 2 decades, only a few individual case reports and...
subspecies , formerly classified as biotype II/2 until 2003, is a rare cause of infant meningitis. Over the past 2 decades, only a few individual case reports and limited case series exist in the English-language literature. Moreover, the pathogenesis of subsp. meningitis in infants is unclear. Here we report a case of meningitis in a 6-week-old infant with hypothyroidism and preceding diarrhea. In this case, was cultured from cerebrospinal fluid, and then subspecies was identified by metagenomic next-generation Sequencing. The infant recovered uneventfully after a 4-week antibiotic course with ceftriaxone and vancomycin. Then combined with the literature of subsp. meningitis in infants, we discuss the possible etiology.
PubMed: 37727275
DOI: 10.2147/IDR.S425637 -
Frontiers in Cellular and Infection... 2021The opportunistic pathogen is one of the few intestinal bacteria that has been consistently linked to colorectal cancer (CRC). This study aimed to identify novel...
OBJECTIVE
The opportunistic pathogen is one of the few intestinal bacteria that has been consistently linked to colorectal cancer (CRC). This study aimed to identify novel -induced pathways in colon epithelial cells that could further explain how contributes to CRC development.
DESIGN AND RESULTS
Transcription profiling of cultured CRC cells that were exposed to revealed the specific induction of oxidoreductase pathways. Most prominently, and genes that encode phase I biotransformation enzymes were responsible for the detoxification or bio-activation of toxic compounds. A common feature is that these enzymes are induced through the Aryl hydrocarbon receptor (AhR). Using the specific inhibitor CH223191, we showed that the induction of was dependent on the AhR both using multiple CRC cell lines as using wild-type C57bl6 mice colonized with . Furthermore, we showed that CYP1 could also be induced by other intestinal bacteria and that a yet unidentified diffusible factor from the secretome (SGS) induces CYP1A enzyme activity in an AhR-dependent manner. Importantly, priming CRC cells with SGS increased the DNA damaging effect of the polycyclic aromatic hydrocarbon 3-methylcholanthrene.
CONCLUSION
This study shows that gut bacteria have the potential to modulate the expression of biotransformation pathways in colonic epithelial cells in an AhR-dependent manner. This offers a novel theory on the contribution of intestinal bacteria to the etiology of CRC by modifying the capacity of intestinal epithelial or (pre-)cancerous cells to (de)toxify dietary components, which could alter intestinal susceptibility to DNA damaging events.
Topics: Animals; Biotransformation; Colorectal Neoplasms; Cytochrome P-450 CYP1A1; Epithelial Cells; Mice; Mice, Inbred C57BL; Receptors, Aryl Hydrocarbon; Streptococcus gallolyticus
PubMed: 34778104
DOI: 10.3389/fcimb.2021.740704 -
Journal of Medical Case Reports Oct 2021Streptococcus gallolyticus subspecies gallolyticus is a known pathogen that causes infective endocarditis, and most cases involve the left heart valves. We present the... (Review)
Review
BACKGROUND
Streptococcus gallolyticus subspecies gallolyticus is a known pathogen that causes infective endocarditis, and most cases involve the left heart valves. We present the first reported case of prosthetic tricuspid valve endocarditis caused by this microorganism. Relevant literature is reviewed.
CASE PRESENTATION
A 67-year-old Jewish female with a history of a prosthetic tricuspid valve replacement was admitted to the emergency department because of nonspecific complaints including effort dyspnea, fatigue, and a single episode of transient visual loss and fever. No significant physical findings were observed. Laboratory examinations revealed microangiopathic hemolytic anemia and a few nonspecific abnormalities. Transesophageal echocardiogram demonstrated a vegetation attached to the prosthetic tricuspid valve. The involved tricuspid valve was replaced by a new tissue valve, and Streptococcus gallolyticus subspecies gallolyticus was grown from its culture. Prolonged antibiotic treatment was initiated.
CONCLUSIONS
Based on this report and the reviewed literature, Streptococcus gallolyticus should be considered as a rare but potential causative microorganism in prosthetic right-sided valves endocarditis. The patient's atypical presentation emphasizes the need for a high index of suspicion for the diagnosis of infective endocarditis.
Topics: Aged; Endocarditis; Endocarditis, Bacterial; Female; Humans; Streptococcal Infections; Streptococcus gallolyticus; Tricuspid Valve
PubMed: 34702343
DOI: 10.1186/s13256-021-03125-5 -
Journal of Microbiology, Immunology,... Dec 2021We report 4 cases of neonatal sepsis caused by Streptococcus gallolyticus. The clinical course was quite similar to early-and late-onset group B streptococcus disease....
We report 4 cases of neonatal sepsis caused by Streptococcus gallolyticus. The clinical course was quite similar to early-and late-onset group B streptococcus disease. None of the mothers had group B streptococcus (GBS) colonization on prenatal screening nor received intrapartum antibiotics. We proposed the sporadic distribution of S. gallolyticus sepsis among neonates was partly due to relatively low colonization rate in adults compared with GBS. Species determination of S. gallolyticus may not be available using conventional microbiological methods and may contribute to underestimation or misclassification. In our series, we highlighted the importance of S. gallolyticus as an important pathogen in neonatal sepsis deserving further surveillance.
Topics: Anti-Bacterial Agents; Female; Humans; Infant, Newborn; Male; Neonatal Sepsis; Streptococcal Infections; Streptococcus agalactiae; Streptococcus gallolyticus; Treatment Outcome
PubMed: 34052145
DOI: 10.1016/j.jmii.2021.05.003 -
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 -
Frontiers in Cellular and Infection... 2019Blood culture-negative endocarditis (BCNE) remains a diagnostic challenge. In our center, despite a systematic and exhaustive microbiological diagnostics strategy, 22%...
Blood culture-negative endocarditis (BCNE) remains a diagnostic challenge. In our center, despite a systematic and exhaustive microbiological diagnostics strategy, 22% of patients with BCNE remain without an identified etiology. In an effort to determine the relevance of using Western blot (WB) for the etiological diagnosis of BCNE in patients with early antibiotic use, we developed specific assays for the major infective endocarditis (IE) causative agents, namely, , and . Our technique was effective to identify the antigenic profiles of the four tested agents, but cross-reactions with . and . antigens were frequent. A scoring method was developed for the diagnosis of and IE using the presence of reactivity to at least two antigenic bands for each bacterium and the positivity to at least one of the Ef300, Ef72, or Ef36 proteic bands for , and positivity for the two Sg75 and Sg97 proteic bands for . We tested these diagnostic criteria in a prospective cohort of 363 patients with suspected IE. Immunoblotting for the diagnosis of IE showed a sensitivity of 100% and a specificity of 99%. The positive and negative predictive values were 73 and 100%, respectively. Regarding infection, immunoblot had a sensitivity of 100% and a specificity of 95%. However, the positive predictive value was 22%, whereas the predictive negative value was 100%. Using WB, we identified a potential etiological agent in 4 of 14 BCNE cases with no identified pathogen. In conclusion, WB constitutes a promising and helpful method to diagnose or IE in patients with early antibiotic uptake and negative blood cultures.
Topics: Antigens, Bacterial; Blotting, Western; Diagnostic Tests, Routine; Endocarditis; Enterococcus faecalis; Gram-Positive Bacterial Infections; Humans; Predictive Value of Tests; Prospective Studies; Sensitivity and Specificity; Staphylococcus aureus; Streptococcus
PubMed: 31572688
DOI: 10.3389/fcimb.2019.00314