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MSphere May 2024Environmental enteric dysfunction (EED) is a subclinical syndrome of altered small intestinal function postulated to be an important contributor to childhood...
Environmental enteric dysfunction (EED) is a subclinical syndrome of altered small intestinal function postulated to be an important contributor to childhood undernutrition. The role of small intestinal bacterial communities in the pathophysiology of EED is poorly defined due to a paucity of studies where there has been a direct collection of small intestinal samples from undernourished children. Sixty-three members of a Pakistani cohort identified as being acutely malnourished between 3 and 6 months of age and whose wasting (weight-for-length -score [WLZ]) failed to improve after a 2-month nutritional intervention underwent esophagogastroduodenoscopy (EGD). Paired duodenal luminal aspirates and duodenal mucosal biopsies were obtained from 43 children. Duodenal microbiota composition was characterized by sequencing bacterial 16S rRNA gene amplicons. Levels of bacterial taxa (amplicon sequence variants [ASVs]) were referenced to anthropometric indices, histopathologic severity in biopsies, expression of selected genes in the duodenal mucosa, and fecal levels of an immunoinflammatory biomarker (lipocalin-2). A "core" group of eight bacterial ASVs was present in the duodenal samples of 69% of participants. was the most prevalent, followed by sp., , , , and . At the time of EGD, none of the core taxa were significantly correlated with WLZ. Statistically significant correlations were documented between the abundances of and and the expression of duodenal mucosal genes involved in immune responses (dual oxidase maturation factor 2, serum amyloid A, and granzyme H). These results suggest that a potential role for members of the oral microbiota in pathogenesis, notably , and species, warrants further investigation.IMPORTANCEUndernutrition among women and children is a pressing global health problem. Environmental enteric dysfunction (EED) is a disease of the small intestine (SI) associated with impaired gut mucosal barrier function and reduced capacity for nutrient absorption. The cause of EED is ill-defined. One emerging hypothesis is that alterations in the SI microbiota contribute to EED. We performed a culture-independent analysis of the SI microbiota of a cohort of Pakistani children with undernutrition who had failed a standard nutritional intervention, underwent upper gastrointestinal tract endoscopy, and had histologic evidence of EED in their duodenal mucosal biopsies. The results revealed a shared group of bacterial taxa in their duodenums whose absolute abundances were correlated with levels of the expression of genes in the duodenal mucosa that are involved in inflammatory responses. A number of these bacterial taxa are more typically found in the oral microbiota, a finding that has potential physiologic and therapeutic implications.
PubMed: 38742887
DOI: 10.1128/msphere.00196-24 -
Cureus Mar 2024A 67-year-old male with coronary artery disease and aortic stenosis after coronary artery bypass graft (CABG) and aortic valve replacement (AVR) presented after a...
A 67-year-old male with coronary artery disease and aortic stenosis after coronary artery bypass graft (CABG) and aortic valve replacement (AVR) presented after a two-day history of dizziness and frequent falls. Initially, he was found to have a subacute infarct of the left temporal lobe, osteomyelitis of the lumbar spine, and an aortic valve vegetation. Further investigations demonstrated gram-positive bacteremia, and, eventually, the causative organism was identified as . He was treated with penicillin and gentamicin in the inpatient setting and then discharged with outpatient intravenous (IV) ceftriaxone for the remainder of the four-week antibiotic course. He did not suffer complications after initiating therapy and recovered. We wish to raise awareness of the existence and complications that can result from endocarditis and encourage further research into effective antibiotic treatment. endocarditis may lead to neurological and orthopedic infective sequelae; understanding and awareness of spp. infections are important to ensure effective treatment of endocarditis.
PubMed: 38659565
DOI: 10.7759/cureus.56904 -
Journal of Oral Microbiology 2024Abiotrophia defectiva, although infrequently occurring, is a notable cause of culture-negative infective endocarditis with limited research on its virulence. Associated...
BACKGROUND
Abiotrophia defectiva, although infrequently occurring, is a notable cause of culture-negative infective endocarditis with limited research on its virulence. Associated with oral infections such as dental caries, exploring its secretome may provide insights into virulence mechanisms. Our study aimed to analyze and characterize the secretome of A. defectiva strain CCUG 27639.
METHODS
Secretome of A. defectiva was prepared from broth cultures and subjected to mass spectrometry and proteomics for protein identification. Inflammatory potential of the secretome was assessed by ELISA.
RESULTS
Eighty-four proteins were identified, with diverse subcellular localizations predicted by PSORTb. Notably, 20 were cytoplasmic, 12 cytoplasmic membrane, 5 extracellular, and 9 cell wall-anchored proteins. Bioinformatics tools revealed 54 proteins secreted via the 'Sec' pathway and 8 via a non-classical pathway. Moonlighting functions were found in 23 proteins, with over 20 exhibiting potential virulence properties, including peroxiredoxin and oligopeptide ABC transporter substrate-binding protein. Gene Ontology and KEGG analyses categorized protein sequences in various pathways. STRING analysis revealed functional protein association networks. Cytokine profiling demonstrated significant proinflammatory cytokine release (IL-8, IL-1β, and CCL5) from human PBMCs.
CONCLUSIONS
Our study provides a comprehensive understanding of A. defectiva's secretome, laying the foundation for insights into its pathogenicity.
PubMed: 38352067
DOI: 10.1080/20002297.2024.2307067 -
Medicine Dec 2023This study used metagenomic next-generation sequencing (mNGS) technology to explore the changes of the microbial characteristics in the lower respiratory tract in...
This study used metagenomic next-generation sequencing (mNGS) technology to explore the changes of the microbial characteristics in the lower respiratory tract in patients with acute exacerbations of bronchiectasis (noncystic fibrosis) to guide clinical treatment and improve patients' quality of life and prognosis. This prospective study included 54 patients with acute exacerbation and 46 clinically stable patients admitted to the Respiratory and Critical Care Medicine Center of the People's Hospital of Xinjiang Uygur Autonomous Region from January 2020 to July 2022. Sputum was subjected to routine microbiological tests, and bronchoalveolar lavage fluid (BALF) samples were subjected to microbiological tests and mNGS of BALF before empirical antibiotic therapy. Serum inflammatory markers (white blood cell count, interleukin-6, procalcitonin, and C-reactive protein) were measured. In addition, we evaluated the pathogen of mNGS and compared the airway microbiome composition of patients with acute exacerbation and control patients. The mean age of our cohort was 56 ± 15.2 years. Eighty-nine patients had positive results by mNGS. There was a significant difference in the detection of viruses between the groups (χ2 = 6.954, P < .01). The fungal species Candida albicans, Pneumocystis jirovecii, and Aspergillus fumigatus were significantly more common in patients with acute exacerbations (χ2 = 5.98, P = .014). The bacterial species Acinetobacter baumannii, Mycobacterium tuberculosis, Haemophilus influenzae, Haemophilus parahaemolyticus, Abiotrophia defectiva, and Micromonas micros were significantly more prevalent in patients with acute exacerbations (χ2 = 4.065, P = .044). The most common bacterial species isolated from the sputum and BALF samples of patients with acute exacerbation was A. baumannii. Chlamydia psittaci was found in 4 patients. In addition, of 77 patients with negative sputum culture, 66 had positive results by mNGS, demonstrating the increased sensitivity and accuracy of mNGS. Patients with acute exacerbation of bronchiectasis tend to have mixed infections in the lower respiratory tract. The frequency of viruses, fungi, and Mycoplasma was higher in these patients. Our findings suggest that mNGS could be used to identify pathogenic microorganisms in these patients, increasing the effectiveness of antibiotic therapy.
Topics: Humans; Adult; Middle Aged; Aged; Prospective Studies; Quality of Life; Bronchiectasis; Microbiota; Respiratory System; Anti-Bacterial Agents; High-Throughput Nucleotide Sequencing; Sensitivity and Specificity
PubMed: 38115299
DOI: 10.1097/MD.0000000000036519 -
IDCases 2023Belonging to the normal oral, gastrointestinal, and urogenital flora, is responsible for 1-2 % of all infective endocarditis (IE) cases. The manifestation of...
Belonging to the normal oral, gastrointestinal, and urogenital flora, is responsible for 1-2 % of all infective endocarditis (IE) cases. The manifestation of endocarditis may by atypical, without fever. Difficult to isolate pathogen requires special culture media. A 45-year-old female was admitted due to anemia and progressive weight loss (8 kg in 6 months). She had a history of benign mitral valve (MV) prolapse and non-stenotic bicuspid aortic valve (BAV). In echocardiography, large vegetations on MV and small vegetation on BAV were found. An enriched medium for fastidious pathogens was used. was identified using biochemical analysis with VITEK-2 Compact. In the fourth week of antibiotic therapy, she required urgent MV replacement due to MV regurgitation progression while vegetation on BAV disappeared. Although patient's frailty and underweight caused prolonged postoperative wound healing, she was transferred to rehabilitation in good conditions. No relapse of IE was observed during five-month follow-up.
PubMed: 37867569
DOI: 10.1016/j.idcr.2023.e01906 -
Journal of Cardiology Cases Oct 2023A 74-year-old woman with a history of mitral valve prolapse with mitral regurgitation was transferred to our hospital due to infective endocarditis. Blood culture...
UNLABELLED
A 74-year-old woman with a history of mitral valve prolapse with mitral regurgitation was transferred to our hospital due to infective endocarditis. Blood culture revealed which is known as a nutritional variant streptococcus. Transesophageal echocardiography revealed posterior leaflet (P2) prolapse due to rupture of tendon chordae with severe mitral regurgitation and vegetation on posterior leaflet. Magnetic resonance imaging (MRI) revealed multiple infarction lesions in left temporal lobe and parietal lobe and mycotic aneurysm formation of right middle cerebral artery. Because cannot be cultured on non-supplemented media, their prevalence may be underreported.
LEARNING OBJECTIVE
A number of causative microorganisms of infective endocarditis have been identified. Streptococci and staphylococci account for 80 % of cases of infective endocarditis. does not grow in ordinary growth media and its prevalence may be underreported. It is important to know causes infective endocarditis with mycotic aneurysm formation.
PubMed: 37818438
DOI: 10.1016/j.jccase.2023.06.002 -
Microbiome Aug 2023Treating oral squamous cell carcinoma (OSCC) introduces new ecological environments in the oral cavity. This is expected to cause changes in the oral microbiome. The...
BACKGROUND
Treating oral squamous cell carcinoma (OSCC) introduces new ecological environments in the oral cavity. This is expected to cause changes in the oral microbiome. The purpose of this study was to gain new information on the salivary microbiome of OSCC patients in order to improve the aftercare of OSCC patients. The aims of this study were to investigate possible changes in the salivary microbiome profiles of OSCC patients before and after cancer treatment and to compare these changes with the profiles of healthy controls.
PATIENTS AND METHODS
Paraffin-stimulated whole saliva samples were collected, and the salivary flow rate was measured from 99 OSCC patients prior to surgical resection of the tumor and other adjuvant therapy. After treatment, 28 OSCC patients were re-examined with a mean follow-up time of 48 months. In addition, 101 healthy controls were examined and sampled. After DNA extraction and purification, the V4 hypervariable region of the 16S rRNA gene was amplified and sequenced using Illumina MiSeq. The merged read pairs were denoised using UNOISE3, mapped to zero-radius operational taxonomic units (zOTUs), and the representative zOTU sequences were assigned a taxonomy using HOMD. Descriptive statistics were used to study the differences in the microbial profiles of OSCC patients before and after treatment and in comparison to healthy controls.
RESULTS
At baseline, the OSCC patients showed a higher relative abundance of zOTUs classified as Streptococcus anginosus, Abiotrophia defectiva, and Fusobacterium nucleatum. The microbial profiles differed significantly between OSCC patients and healthy controls (F = 5.9, p < 0.001). Alpha diversity of the salivary microbiome of OSCC patients was decreased at the follow-up, and the microbial profiles differed significantly from the pre-treatment (p < 0.001) and from that of healthy controls (p < 0.001).
CONCLUSIONS
OSCC patients' salivary microbiome profile had a higher abundance of potentially pathogenic bacteria compared to healthy controls. Treatment of the OSCC caused a significant decrease in alpha diversity and increase in variability of the salivary microbiome, which was still evident after several years of follow-up. OSCC patients may benefit from preventive measures, such as the use of pre- or probiotics, salivary substitutes, or dietary counseling. Video Abstract.
Topics: Humans; Mouth Neoplasms; Carcinoma, Squamous Cell; RNA, Ribosomal, 16S; Saliva; Microbiota
PubMed: 37542310
DOI: 10.1186/s40168-023-01613-y -
Frontiers in Medicine 2023A rare pathogen of Infective Endocarditis (IE), the , has been known to trigger life-threatening complications. The case discussed here is of a teenager with brain...
INTRODUCTION
A rare pathogen of Infective Endocarditis (IE), the , has been known to trigger life-threatening complications. The case discussed here is of a teenager with brain infarction and subarachnoid hemorrhage caused by IE due to .
CASE REPORT
A 15-year-old girl with movement disorders involving the left limbs and intermittent fevers was admitted to the hospital. A head CT scan revealed cerebral infarction in the right basal ganglia and subarachnoid hemorrhage. Moreover, vegetation on the mitral valve were confirmed by echocardiography. The blood cultures were found to be positive for Gram-positive streptococcus and identified by Vitek mass spectrometry as . She was prescribed vancomycin antibacterial therapy and underwent a surgical mitral valve replacement.
CONCLUSION
This case is suggestive of the fact that is a rare but crucial pathogen of IE-associated stroke. Obtaining early blood cultures and using microbial mass spectrometry could help achieve an accurate diagnosis. Moreover, reasonable anti-infective medications and surgical interventions need to be combined to avoid and/or manage severe complications.
PubMed: 37206473
DOI: 10.3389/fmed.2023.1117474 -
European Journal of Case Reports in... 2023Infective endocarditis (IE) is a well-described infectious disease, one with increased morbidity and mortality being the third or fourth most common life-threatening...
UNLABELLED
Infective endocarditis (IE) is a well-described infectious disease, one with increased morbidity and mortality being the third or fourth most common life-threatening infection syndrome. is a non-motile, catalase negative, gram-positive coccus in a chain, which can be isolated from the oral cavity, intestinal, and genitourinary tracts. IE due to this agent is rare and associated with heart valve destruction, congestive heart failure, and high embolisation rates, these being the major mortality causes. We present a case of IE due to this agent, complicated with a stroke, and splenic and renal infarction, with the need for aortic valve replacement. This article highlights the gaps of knowledge left by the rarity of this disease, which range from its diagnosis to its treatment, and what we need to mitigate such gaps, supported with a case description of a successful treatment of this infection.
LEARNING POINTS
Infective endocarditis due to has usually an indolent course, but the embolisation potential is very high.The major causes of mortality with this species are congestive heart failure due to valve destruction and the presence of multiple emboli.Surgical intervention rates are high with , reaching 50% of cases.
PubMed: 36819655
DOI: 10.12890/2023_003702 -
IDCases 2023is an uncommon and potentially severe cause of bacterial meningitis that can be seen in the setting of neurosurgical procedures. We describe here a case of meningitis...
INTRODUCTION
is an uncommon and potentially severe cause of bacterial meningitis that can be seen in the setting of neurosurgical procedures. We describe here a case of meningitis in a patient with VP shunt revision.
CASE REPORT
The patient is a 59-year-old female with VP shunt placed several years prior in the setting of normal pressure hydrocephalus. She underwent successful shunt repair following worsening gait abnormalities. On post-operative day 8 she was brought to the emergency room with fevers, photophobia and altered mentation. CSF cultures returned positive for and she was treated with intravenous vancomycin. Due to the presence of retained hardware she was discharged on chronic suppressive therapy with oral amoxicillin.
CONCLUSION
This case illustrates as a cause of bacterial meningitis following neurosurgical intervention. It is important to consider this fastidious organism and tailor antimicrobial therapy appropriately to prevent significant morbidity and mortality. As was the case with our patient, suppressive therapy may be warranted in setting of retained hardware.
PubMed: 36817943
DOI: 10.1016/j.idcr.2023.e01708