Streptococcus Anginosus Research Articles

STREPTOCOCCUS ANGINOSUS PHARYNGITIS: A CASE PRESENTATION, TREATMENT, AND EVOLUTION

Pharyngitis, the inflammation of the pharynx, can be caused by non-infectious, environmental factors and infectious agents, like viruses, bacteria, and fungi. While some etiologies may only need symptomatic or no treatment, others require highly supportive and/or antimicrobial intervention to cure and prevent negative outcomes. Thus, correct diagnosis is important to properly manage the patient’s illness and avoid, for example, excessive use of antibiotics. This article presents the clinical case of an immunocompetent young woman who went to the general practitioner for symptoms of pharyngitis. After clinical, laboratory, and microbiological evaluation, the results showed bacterial pharyngitis with an uncommon opportunistic pathogen, Streptococcus anginosus, that occurred after a viral respiratory infection. The evolution was favorable without antibiotic treatment, with the infection healing after a few days of symptom control medication.

Streptococcus angriness isolated from Patients with Acute Infection following Surgical Tooth Extraction

In this study, 250 individuals with acute infection following surgical tooth extraction were treated at a Hilla dental clinic and cultivated at 37°C for 18–24 hours. They cultured on several selective medium at 37°C for 18–24 hours. Identification of Streptococcus anginosus was based on colonial morphology, microscopically, and biochemical tests, and all scientific specimens were successful cultures. Of 250 specimens, only 25(10%) were biochemically identified as Strep. anginosus, while 225(90%) were associated with other microorganisms. Hemolysin-producing Strep. anginosus isolates have been studied. 10(66.66%) isolates produced hemolysin in blood agar that formed a clearance sector around the colonies and a streak on the plate after 24 hours of incubation at 37°C. Strep. anginosus isolates were also tested for siderophores production, 5(33.33%) Strep. anginosus isolates produce siderophores. All bacterial isolates provide protease to hydrolyze protein. After 24 hours of incubation, all Strep. anginosus isolates were able to hydrolyze protein using protease enzyme (100%) when tested using M9 (supported by 20% glucose and 1% csaien). Adding 3ml of 5% Trichloroacetic acid gave the colony a clean hallo. Quantitative biofilm development tests were performed in a microtiter using Trypticase Soy Broth with 1% glucose. To improve accuracy, this assay was done three times. All Strep. anginosus isolates were biofilm former (100%), 12/15(80%) were strong biofilm formers, and 3/15 (20%) were mild biofilm formers. However, the antibiotic disc diffusion test using six clinically important antibiotics showed that most Strep. anginosus isolates were extremely resistant to the antibiotics, especially the ?-lactams, including Amoxicillin 13(86.6%), Cefixime 12(80%), Ceftriaxone 12(80%), Meropenem, 11(73.33%) Cefotaxime 10(66.66%), and Imipenem 9(60%).

Increase in Odontogenic Cervicofacial Infection Requiring Hospitalization in Children During COVID-19 Quarantine

The aim of this study was to evaluate the effect of Coronavirus disease-2019 (COVID-19) quarantines on children hospitalizedfor odontogenic cervicofacial infection. The data of patients aged 1 month-18 years, who were followed up with the diagnosis ofodontogenic cervicofacial infection in Çanakkale Onsekiz Mart University Hospital between January 2019 and June 2021 wasexamined, retrospectively. Thirteen patients with a mean age of 8.5±3.8, 7 of whom were male were included in the study. Three of the patients were diagnosed in the pre-COVID-19 period and 10 of them were diagnosed in the second year of COVID-19. Five patients had a known history of dental caries. On physical examination, it was determined that all patients had dental caries in the area corresponding to the infection site. Four patients required abscess drainage, all of whom were presenting in the second year of COVID-19, we isolated Eikenella corrodens, Streptococcus anginosus and Streptococcus intermedius microorganisms in 3 patients. The mean duration of hospitalization was 5.3±3 days. In conclusion, COVID-19 quarantine causes an increase in odontogenic cervicofacial infection requiring intravenous antibiotics and abscess drainage.

Diversity of CRISPR-Cas type II-A systems in Streptococcus anginosus.

Streptococcus anginosus is a commensal Streptococcal species that is often associated with invasive bacterial infections. However, little is known about its molecular genetic background. Many Streptococcal species, including S. anginosus, harbor clustered regularly interspaced short palindromic repeats (CRISPR)-Cas systems. A CRISPR-Cas type II-A system as well as a type II-C system have been reported for this species. To characterize the CRISPR-Cas type II systems of S. anginosus in more detail, we conducted a phylogenetic analysis of Cas9 sequences from CRISPR-Cas type II systems with a special focus on streptococci and S. anginosus. In addition, a phylogenetic analysis of S. anginosus strains based on housekeeping genes included in MLST analysis, was performed. All analyzed Cas9 sequences of S. anginosus clustered with the Cas9 sequences of CRISPR type II-A systems, including the Cas9 sequences of S. anginosus strains reported to harbor a type II-C system. The Cas9 genes of the CRISPR-Cas type II-C systems of other bacterial species separated into a different cluster. Moreover, analyzing the CRISPR loci found in S. anginosus, two distinct csn2 genes could be detected, a short form showing high similarity to the canonical form of the csn2 gene present in S. pyogenes. The second CRISPR type II locus of S. anginosus contained a longer variant of csn2 with close similarities to a csn2 gene that has previously been described in Streptococcus thermophilus. Since CRISPR-Cas type II-C systems do not contain a csn2 gene, the S. anginosus strains reported to have a CRISPR-Cas type II-C system appear to carry a variation of CRISPR-Cas type II-A harboring a long variant of csn2.

Pertinence of Streptococcus anginosus group in intracerebral abscesses in the era of extended antibiotic resistance

Aims• To study the incidence of Streptococcus anginosus group (SAG) in pyogenic or community acquired intra cerebral abscess.• To understand the risk factors for the same.• To analyze the specific radiological features and clinical outcome after surgery and antibiotic therapy. MethodsThis is a retrospective observational study of case series over a period of one year. Patients diagnosed with intracerebral abscess were included in the study. Pus collected from were received in the laboratory and processed according to the standard protocols. Data regarding the clinical findings and demographics were collected from medical records. FindingsA total of 202 samples were studied. 103 were found to be pyogenic. SAG were isolated from 21 samples (20.38%) and all the isolates were sensitive to Penicillin. Age of the patients ranged from 18months to 68years. Male preponderance was noted with male to female ratio of 4:1. Otogenic infections were the most common predisposing factors and focus of infection could not be ascertained in 5 patients. All patients were treated with surgical intervention and antibiotics (Vancomycin, Amikacin and Metronidazole) for 6 weeks and recovery was remarkable. One patient succumbed to the illness. ConclusionSAG can be an aggressive pathogen with propensity for abscess formation. Chronic Suppurative Otitis Media (CSOM) is still a major cause of intracerebral abscess in developing country like India which is a benign and curable disease and should not be neglected. Injudicious use of antibiotics and negligence regarding the dose and duration of therapy from both patients and health care providers is the major cause for common infections to become more difficult to treat and succumbing to complications.

Association between monoaromatic hydrocarbons exposure and vaginal microbiota disorder in recurrent implantation failure

Recurrent implantation failure (RIF) is a significant challenge facing population development, with the impact of monoaromatic hydrocarbons (MACHs) exposure on embryo implantation and reproductive hazards remaining largely unclear. As such, we conducted a prospective randomized controlled cohort study to explore the potential correlations between exposure to MACHs and vaginal microbiota, and their potential adverse effects on embryo implantation. Our findings suggest that exposure to Mono(2-ethylhexyl) phthalate (MEHP), Methyl N-methylanthranilate, and Benzene is closely linked with the disruption of the microbial community in the RIF group. The RIF group thus exhibited a fragile vaginal microbial community structure, with lower lactic acid bacterial abundance, and higher potential pathogenic bacterial abundance, such as Streptococcus anginosus and Peptoniphilus asaccharolyticus. This abnormal vaginal microbiota composition was associated with adverse pregnancy outcomes, with sphingolipid metabolism dysfunction being a key factor in abnormal microbiota leading to such outcomes. Additionally, we found that exposure to Methyl N-methylanthranilate and MEHP was closely associated with decreased abundance of Lactobacillus (including L.crispatus and L.jensenii) and diminished reproductive tract protective barrier function. Our study underscores the significance of acknowledging the impact of MACHs, a ubiquitous everyday exposure, on female fertility.

Studies of Streptococcus anginosus Virulence in Dictyostelium discoideum and Galleria mellonella Models.

For many years, Streptococcus anginosus has been considered a commensal colonizing the oral cavity, as well as the gastrointestinal and genitourinary tracts. However, recent epidemiological and clinical data designate this bacterium as an emerging opportunistic pathogen. Despite the reported pathogenicity of S. anginosus, the molecular mechanism underpinning its virulence is poorly described. Therefore, our goal was to develop and optimize efficient and simple infection models that can be applied to examine the virulence of S. anginosus and to study host-pathogen interactions. Using 23 S. anginosus isolates collected from different infections, including severe and superficial infections, as well as an attenuated strain devoid of CppA, we demonstrate for the first time that Dictyostelium discoideum is a suitable model for initial, fast, and large-scale screening of virulence. Furthermore, we found that another nonvertebrate animal model, Galleria mellonella, can be used to study the pathogenesis of S. anginosus infection, with an emphasis on the interactions between the pathogen and host innate immunity. Examining the profile of immune defense genes, including antimicrobial peptides, opsonins, regulators of nodulation, and inhibitors of proteases, by quantitative PCR (qPCR) we identified different immune response profiles depending on the S. anginosus strain. Using these models, we show that S. anginosus is resistant to the bactericidal activity of phagocytes, a phenomenon confirmed using human neutrophils. Notably, since we found that the data from these models corresponded to the clinical severity of infection, we propose their further application to studies of the virulence of S. anginosus.

Pre-treatment oral microbiome analysis and salivary Stephan curve kinetics in white spot lesion development in orthodontic patients wearing fixed appliances. A pilot study

BackgroundWhite spot lesions (WSLs) are a formidable challenge during orthodontic treatment, affecting patients regardless of oral hygiene. Multifactorial in nature, amongst potential contributors to their development are the microbiome and salivary pH. The aim of our pilot study is to determine if pre-treatment differences in salivary Stephan curve kinetics and salivary microbiome features correlate with WSL development in orthodontic patients with fixed appliances. We hypothesize that non-oral hygiene determined differences in saliva could be predictive of WSL formation in this patient population through analysis of salivary Stephan curve kinetics, and that these differences would further manifest as changes in the oral microbiome.MethodsIn this prospective cohort study, twenty patients with initial simplified oral hygiene index scores of “good” that were planning to undergo orthodontic treatment with self-ligating fixed appliances for at least 12 months were enrolled. At pre-treatment stage, saliva was collected for microbiome analysis, and at 15-minute intervals after a sucrose rinse over 45 min for Stephan curve kinetics.Results50% of patients developed a mean 5.7 (SEM: 1.2) WSLs. There were no differences in saliva microbiome species richness, Shannon alpha diversity or beta diversity between the groups. Capnocytophaga sputigena exclusively and Prevotella melaninogenica predominantly were found in WSL patients, while Streptococcus australis was negatively correlated with WSL development. Streptococcus mitis and Streptococcus anginosus were primarily present in healthy patients. There was no evidence to support the primary hypothesis.ConclusionsWhile there were no differences in salivary pH or restitution kinetics following a sucrose challenge and no global microbial differences in WSL developers, our data showed change in salivary pH at 5 min associated with an abundance of acid-producing bacteria in saliva. The results suggest salivary pH modulation as a management strategy to inhibit the abundance of caries initiators. Our study may have uncovered the earliest predecessors to WSL/caries development.

Meta-analysis reveals Helicobacter pylori mutual exclusivity and reproducible gastric microbiome alterations during gastric carcinoma progression

ABSTRACT Accumulating evidence shows that the gastric bacterial community may contribute to the development of gastric cancer (GC). However, the reported alterations of gastric microbiota were not always consistent among the literature. To assess reproducible signals in gastric microbiota during the progression of GC across studies, we performed a meta-analysis of nine publicly available 16S datasets with standard tools of the state-of-the-art. Despite study-specific batch effect, significant changes in the composition of the gastric microbiome were found during the progression of gastric carcinogenesis, especially when the Helicobacter pylori (HP) reads were removed from analyses to mitigate its compositional effect as they accounted for extremely large proportions of sequencing depths in many gastric samples. Differential microbes, including Fusobacterium, Leptotrichia, and several lactic acid bacteria such as Bifidobacterium, Lactobacillus, and Streptococcus anginosus, which were frequently and significantly enriched in GC patients compared with gastritis across studies, had good discriminatory capacity to distinguish GC samples from gastritis. Oral microbes were significantly enriched in GC compared to precancerous stages. Intriguingly, we observed mutual exclusivity of different HP species across studies. In addition, the comparison between gastric fluid and mucosal microbiome suggested their convergent dysbiosis during gastric disease progression. Taken together, our systematic analysis identified novel and consistent microbial patterns in gastric carcinogenesis.

Anaerobic biodegradation of anthracene by oral Firmicutes isolates from smokers and its potential pathway

Exposure to polycyclic aromatic hydrocarbons (PAHs) from tobacco smoke has been linked to many negative health effects. Studies on the biodegradation of PAHs by human microbiota and detailed pathways for their anaerobic biodegradation are scarce despite their importance in getting rid of these toxic compounds. In a previous study for our group, we determined the ability of oral bacterial isolates in the anaerobic biodegradation of anthracene as a model of PAHs. Three isolates with the highest anthracene degradation ability were selected for the present study which include Limosilactobacillus fermentum, Veillonella parvula, and Streptococcus anginosus. In this study, we aimed at exploring and elucidating the anthracene anaerobic biodegradation pathways in selected Firmicutes oral isolates. Metabolites throughout the pathway were detected by gas chromatography coupled with mass spectroscopy (GC-MS) using anthracene as sole source of carbon. After incubation for 3 days, anthracene was undetected in the supernatant of L. fermentum and V. parvula, while a residual of 3% of anthracene was detected in presence of S. anginosus. Results revealed that anaerobic biodegradation by L. fermentum and V. parvula started with hydroxylation and dehydrogenation producing 9,10- anthraquinone and ended up with simpler structures such as catechol, while S. anginosus hydroxylation for anthracene resulted in the production of 1,2-anthracenediol and ended up with catechol and phthalic acid. The biodegradation of anthracene by oral bacteria could convert it to other toxic metabolites such as anthraquinone and catechol which were reported to have potential carcinogenic effects. Moreover, fatty acids detected as biodegradation metabolites could be one of the causes of smokers’ heart-related diseases. Thus, this study explored oral metabolites resulting from smoking under anaerobic conditions towards elucidating the role of oral microbiota in health and disease states.

Abstract 5910: Prospective platform to define microbiome correlates of metastasis and therapy resistance in early onset and average onset gastrointestinal cancers

Abstract Background: The incidence of early onset (EO) gastrointestinal (GI) cancers prior to age 50 is rising, and the etiology is unknown. The gut microbiome may contribute to GI cancer pathogenesis, though how bacteria drive metastasis and treatment resistance is not known. Purpose: To define the microbiome contribution to EO-GI cancers and metastasis by analyzing longitudinal samples from previously untreated patients with GI cancers. Methods: We designed a prospective biospecimen collection platform. We selected patients with newly diagnosed, previously untreated colorectal cancer (CRC) and esophagogastric cancer (EGC). We collected stool, biopsy or surgical tissue, and peripheral blood mononuclear cells (PBMCs) at baseline prior to treatment and at each restaging scan for patients with metastatic disease. For those with locally advanced disease, we collected samples at baseline and after each treatment phase (surgery, radiation, chemotherapy). Stool samples were analyzed using shotgun sequencing. Tissue samples were banked for further analysis. Clinical data was manually curated. Relative abundances of bacteria at the species level were compared between groups. Alpha diversity was calculated using the inverse Simpson index and compared between groups using the Wilcoxon signed-rank test. Beta diversity was analyzed using the Bray-Curtis dissimilarity matrix and compared using PERMANOVA. Multivariate association between species abundance and clinical covariates was performed using MaAsLin2 R package. Results: We analyzed a total of 150 stool samples from 76 patients (colorectal n=53, esophagogastric n=23), including up to 6 samples from a single patient over time. Mean alpha diversity did not differ significantly by primary site or age at diagnosis in patients with CRC but was higher in stage IV compared with stage I disease (P=0.054). Beta diversity was significantly different between samples from patients with right- compared with left-sided CRC (P=0.005) but did not differ significantly by diagnosis age (<50 vs. > 50). Among those with EGC, mean alpha diversity was not significantly different in samples from patients with esophagus or gastroesophageal junction (proximal) tumors compared with gastric (distal) tumors and did not differ significantly by age group. Beta diversity was significantly different between patients with EGC over 50 compared with those under 50 (P=0.002). When CRC baseline samples were examined, several bacterial species were associated with age <50 at diagnosis, including Streptococcus anginosus group (P=0.001), Solobacterium moorei (P=0.013), and Firmicutes bacterium CAG83 (P=0.016). Conclusions/Future Directions: Microbiome composition may cluster by primary tumor site and age at diagnosis in patients with previously untreated GI cancers. Functional analysis and is ongoing and will be presented. Citation Format: Melissa A. Lumish, Asha R. Saxena, Nicholas Waters, Anqi Dai, Saskia Hartner, Teng Fei, Matthew Drescher, Jonathan Bermeo, Dorina Ismailgeci, Maggie Fox, Yelena Y. Janjigian, Luis A. Diaz, Martin R. Weiser, Jonathan Peled, Marcel van den Brink, Karuna Ganesh. Prospective platform to define microbiome correlates of metastasis and therapy resistance in early onset and average onset gastrointestinal cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5910.

Parapneumonic effusion in children: Rapid pathogen detection in pleural fluid using multiplex bacterial PCR.

Parapneumonic effusion in children: Rapid pathogen detection in pleural fluid using multiplex bacterial PCR.

Cerebral abscesses with odontogenic origin: a population-based cohort study

ObjectivesRecent studies have indicated that cerebral abscess (CA) patients with odontogenic origin are on the rise. However, CA patients are often poorly characterized and with an unknown etiologic background. The purpose of this study is to identify and characterize CA patients that may have an odontogenic origin based on microbiologic, radiographic, and/or clinical findings.Materials and methodsThis is a population-based cohort study analyzing retrospective and prospective data from CA patients. Radiographic examinations of panoramic radiographs (PRs) or computed tomography (CT) scans were conducted. CA patients characterized with odontogenic origin required the fulfilment of the following criteria on admission: (1) Oral pathologic conditions were the only bacterial infections present, (2) oral microorganisms were isolated in the purulent exudate from the brain, and (3) radiographically and/or clinical recordings of oral pathologic conditions.ResultsA total of 44 patients could be included in this study of which 25 (57%) were characterized as having CA with a likely odontogenic origin. Type two diabetes (T2D) (p = 0.014) and microorganisms of the Streptococcus anginosus group (SAG) (p < 0.01) were overrepresented in patients with CAs of odontogenic origin.ConclusionsOdontogenic infections may cause CAs to a greater extent than previously assumed. T2D was overrepresented among patients with odontogenic CA. When microorganisms of the SAG were isolated from the brain pus, CA patients had a predisposing odontogenic or sinus infection.Clinical relevanceThe identification of patients with a likely odontogenic CA will contribute to understanding the etiology of the infectious disease and highlighting the importance of preserving oral health.

The root canal microbiome diversity and function. A whole-metagenome shotgun analysis.

To evaluate the root canal microbiome composition and bacterial functional capability in cases of primary and secondary apical periodontitis utilizing whole-metagenome shotgun sequencing. Twenty-two samples from patients with primary root canal infections, and 18 samples obtained from previously treated teeth currently diagnosed with apical periodontitis were analysed with whole-metagenome shotgun sequencing at a depth of 20 M reads. Taxonomic and functional gene annotations were made using MetaPhlAn3 and HUMAnN3 software. The Shannon and Chao1 indices were utilized to measure alpha diversity. Differences in community composition were evaluated utilizing analysis of similarity (ANOSIM) using Bray-Curtis dissimilarities. The Wilcoxon rank sum test was used to compare differences in taxa and functional genes. Microbial community variations within a community were significantly lower in secondary relative to primary infections (alpha diversity p = .001). Community composition was significantly different in primary versus secondary infection (R = .11, p = .005). The predominant taxa observed among samples (>2.5%) were Pseudopropionibacterium propionicum, Prevotella oris, Eubacterium infirmum, Tannerella forsythia, Atopobium rimae, Peptostreptococcus stomatis, Bacteroidetes bacterium oral taxon 272, Parvimonas micra, Olsenella profusa, Streptococcus anginosus, Lactobacillus rhamnosus, Porphyromonas endodontalis, Pseudoramibacter alactolyticus, Fusobacterium nucleatum, Eubacterium brachy and Solobacterium moorei. The Wilcoxon rank test revealed no significant differences in relative abundances of functional genes in both groups. Genes with greater relative abundances (top 25) were associated with genetic, signalling and cellular processes including the iron and peptide/nickel transport system. Numerous genes encoding toxins were identified: exfoliative toxin, haemolysins, thiol-activated cytolysin, phospholipase C, cAMP factor, sialidase, and hyaluronic glucosaminidase. Despite taxonomic differences between primary and secondary apical periodontitis, the functional capability of the microbiomes was similar.

Elderly onset atypical Lemierre’s syndrome concurrent with a rheumatoid vasculitis sacral ulcer infection: a case report

BackgroundTypical Lemierre’s syndrome is usually secondary to an oropharyngeal infection. Recently, several cases following a primary infection site other than the oropharynx have been reported as atypical Lemierre’s syndrome; although, these primary lesions are limited to the head and neck. This is the first case potentially sequential to infectious foci outside the head and neck.Case presentationWe describe an atypical Lemierre’s syndrome in a 72-year-old woman with rheumatoid arthritis, which occurred during the treatment of Streptococcus anginosus bacteremia acquired from a sacral ulcer infection related to rheumatoid vasculitis. At first, the symptoms resolved after the initial administration of vancomycin for the bacteremia caused by methicillin-resistant Staphylococcus aureus and Streptococcus anginosus that entered via a sacral ulcer. On the 8th day, the patient developed a fever of 40 °C and unexpectedly required 10 L of oxygen due to rapid deterioration of oxygenation temporarily. Immediately contrast-enhanced computed tomography was performed to investigate systemic thrombosis including pulmonary embolism. Afterward, the newly formed thrombi at the right external jugular vein, bilateral internal jugular veins, and the right small saphenous vein were detected, and apixaban was started. On the 9th day, the patient again had an intermittent fever of 39.7 °C, and continuous Streptococcus anginosus bacteremia was revealed; subsequently, clindamycin was administered. On the 10th day, she developed a left hemothorax; consequently, apixaban was discontinued, and a thoracic drain was inserted. She repeatedly had an intermittent fever of 40.3 °C, and contrast-enhanced computed tomography detected an abscess formation at the left parotid gland, pterygoid muscle group, and masseter muscle. After Lemierre’s syndrome was diagnosed in combination with the abovementioned jugular vein thrombus, clindamycin was replaced with meropenem, and vancomycin was increased. Swelling of the lower part of the left ear became prominent with delay and peaked at approximately the 16th day. The subsequent treatment course was favorable, and she was discharged on the 41st day.ConclusionClinicians should consider Lemierre’s syndrome as the differential diagnosis of internal jugular vein thrombosis occurring during sepsis, even though an antibiotic is administered or a primary infection site is anything besides the oropharynx.

Dalbavancin (Xydalba)

&#x0D; CADTH reimbursement reviews are comprehensive assessments of the clinical effectiveness and cost-effectiveness, as well as patient and clinician perspectives, of a drug or drug class.&#x0D; The assessments inform non-binding recommendations that help guide the reimbursement decisions of Canada's federal, provincial, and territorial governments, with the exception of Quebec.&#x0D; This review assesses Dalbavancin (Xydalba) for injection, 500 mg (as dalbavancin hydrochloride) per vial, lyophilized powder for solution, IV infusion.&#x0D; Indication: Treatment of adults with acute bacterial skin and skin structure infections caused by susceptible isolates of the following gram-positive micro-organisms: Staphylococcus aureus (including methicillin-susceptible and methicillin-resistant strains), Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus dysgalactiae, Streptococcus anginosus group (including Streptococcus anginosus, Streptococcus intermedius, Streptococcus constellatus), and Enterococcus faecalis (vancomycin-susceptible strains).&#x0D;

Using Microbiology Culture in Pediatric Appendicitis to Risk Stratify Patients: A Cohort Study.

Background: We sought to investigate the value of intra-operative microbiology samples in pediatric appendicitis. Proposed benefits include tailoring post-operative antimicrobial management, risk-stratifying patients, and reducing post-operative intra-abdominal abscess formation. Patients and Methods: All cases of appendicitis managed with appendicectomy in a single center were collected from January 2015 to August 2020. Intra-operative microbiology samples were taken routinely. Post-operative outcomes were analyzed with reference to culture and sensitivity results. Histologic findings were further categorized as normal, simple, or complex. Results: Six hundred seventy-eight children had appendicectomies, and 608 had both microbiology and histology samples taken. Intra-abdominal fluid collection and subsequent intervention rates were 22% and 9%, respectively. There were more collections in those with a culture positive result (p < 0.001), and those growing each of three recognized organisms, Escherichia coli (p < 0.001), Pseudomonas aeruginosa (p = 0.01), and Streptococcus anginosus group (p < 0.001). Intervention rate was higher in the culture-positive result group (p = 0.002) and the Streptococcus anginosus group (p < 0.001). Conclusions: This study shows an increased risk of developing a collection with the isolation of one of three key organisms (Escherichia coli, Pseudomonas aeruginosa, Streptococcus anginosus group). Sersoal swabs are an effective and practical method of gathering information on organisms. Microbiologic yield was correlated to the severity of appendicitis. Isolation of Streptococcus anginosus increases the incidence of collections to 50%. This is useful to empower surgeons to prognosticate patients' potential outcomes based on both intra-operative, and microbiologic findings, and is useful in counseling patients and managing expectations. A prolonged course of antibiotic agents or higher dose may mitigate this risk.

Comparative Genomic Study of Streptococcus anginosus Reveals Distinct Group of Urinary Strains.

Streptococcus anginosus is a prevalent member of the human flora. While it has been found in the microbiota of "healthy" asymptomatic individuals, it has also been associated with genitourinary tract infections and bacteremia. Based upon multilocus sequence analysis, two subspecies and two genomosubspecies have been characterized for the species. We previously conducted whole-genome sequencing of 85 S. anginosus isolates from the urinary tract. Here, we present genomic analysis of this species, including isolates from the urinary tract as well as gut and fecal, vaginal, oral, respiratory, and blood and heart samples. Average nucleotide identity and core genome analysis revealed that these strains form two distinct groups. Group 1 is comprised of the S. anginosus type strain and other previously identified S. anginosus subspecies and genomosubspecies, including isolates from throughout the human body. In contrast, group 2 consists of predominantly urinary streptococci (n = 77; 85.6%). Both of these S. anginosus groups are distinct from other members of the Streptococcus anginosus group (SAG) species S. intermedius and S. constellatus. Genes conserved among all strains of one group but not in any strains in the other group were next identified. Group 1 strains included genes found in S. intermedius and S. constellatus, suggesting that they were lost within the ancestor of the group 2 strains. In contrast, genes unique to the group 2 strains were homologous to more distant streptococci, indicative of acquisition via horizontal gene transfer. These genes are ideal candidates for use as marker genes to distinguish between the two groups in the human microbiota. IMPORTANCE Whole-genome analysis of S. anginosus strains provides greater insight into the diversity of this species than from marker genes alone. Our investigation of 166 publicly available S. anginosus genomes via average nucleotide identity and core genome analysis revealed two phylogenomically distinct groups of this species, with one group almost exclusively consisting of isolates from the urinary tract. In contrast, only 8 urinary strains were identified within the other group, which contained the S. anginosus type strain, as well as all identified subspecies and genomosubspecies. While genomic analysis suggested that this urinary group of S. anginosus is genomically different from the previously characterized S. anginosus subspecies, phenotypic characterization is still needed. Given prior reports of the prevalence of S. anginosus in the urinary tract of both continent and incontinent females, future studies are needed to investigate if the symptom state of the urinary tract is associated with these two different groups.

Changes in Etiology and Clinical Outcomes of Pleural empyema during the COVID-19 Pandemic.

Healthcare-seeking behavior changed during the COVID-19 pandemic and might alter the epidemiology of pleural empyema. In this study, the incidence, etiology and outcomes of patients admitted for pleural empyema in Hong Kong in the pre-COVID-19 (January 2015-December 2019) and post-COVID-19 (January 2020-June 2022) periods were compared. Overall, Streptococcus pneumoniae was the predominant organism in <18-year-old patients, while Streptococcus anginosus, anaerobes and polymicrobial infections were more frequent in adults. In the post-COVID-19 period, a marked decline in the incidence of pleural empyema in children was observed (pre-COVID-19, 18.4 ± 4.8 vs. post-COVID-19, 2.0 ± 2.9 cases per year, p = 0.036), while the incidence in adults remained similar (pre-COVID-19, 189.0 ± 17.2 vs. post-COVID-19, 198.4 ± 5.0 cases per year; p = 0.23). In the post-COVID-19 period, polymicrobial etiology increased (OR 11.37, p < 0.0001), while S. pneumoniae etiology decreased (OR 0.073, p < 0.001). In multivariate analysis, clinical outcomes (length of stay, ICU admission, use of intrapleural fibrinolytic therapy, surgical intervention, death) were not significantly different in pre- and post-COVID-19 periods. In conclusion, an increase in polymicrobial pleural empyema was observed during the pandemic. We postulate that this is related to the delayed presentation of pneumonia to hospitals.

Novel dithiocarbamate derivatives are effective copper-dependent antimicrobials against Streptococcal species.

Despite the availability of several vaccines against multiple disease-causing strains of Streptococcus pneumoniae, the rise of antimicrobial resistance and pneumococcal disease caused by strains not covered by the vaccine creates a need for developing novel antimicrobial strategies. N,N-dimethyldithiocarbamate (DMDC) was found to be a potent copper-dependent antimicrobial against several pathogens, including S. pneumoniae. Here, DMDCs efficacy against Streptococcal pathogens Streptococcus pyogenes, Streptococcus agalactiae, and Streptococcus anginosus was tested using bactericidal and inductively coupled plasma - optical emission spectrometry. After confirming DMDC as broad-spectrum streptococcal antimicrobial, DMDC was derivatized into five compounds. The derivatives' effectiveness as copper chelators using DsRed2 and as copper-dependent antimicrobials against S. pneumoniae TIGR4 and tested in bactericidal and animal models. Two compounds, sodium N-benzyl-N-methyldithiocarbamate and sodium N-allyl-N-methyldithiocarbamate (herein "Compound 3" and "Compound 4"), were effective against TIGR4 and further, D39 and ATCC® 6303™ _(a type 3 capsular strain). Both Compound 3 and 4 increased the pneumococcal internal concentrations of copper to the same previously reported levels as with DMDC and copper treatment. However, in an in vivo murine pneumonia model, Compound 3, but not Compound 4, was effective in significantly decreasing the bacterial burden in the blood and lungs of S. pneumoniae-infected mice. These derivatives also had detrimental effects on the other streptococcal species. Collectively, derivatizing DMDC holds promise as potent bactericidal antibiotics against relevant streptococcal pathogens.