Group Streptococci Research Articles

Bugs Behind the Bulging Eyeball: Microbiology and Antibiotic Management in Orbital Cellulitis With or Without Subperiosteal Abscess.

The objective of this study is to describe causative pathogens and current antibiotic management among hospitalized children with orbital cellulitis. This retrospective study, performed at a tertiary care children's health system, included patients up to 18 years old who presented with radiographic evidence of orbital cellulitis from 2012 to 2019. Of the 298 patients included in the study, 103 had surgery and an intraoperative culture obtained. A pathogen was recovered in 86 cultures (83.5%). The most common pathogens were Streptococcus anginosus group (26.2%), Streptococcus pyogenes (11.7%), methicillin-susceptible Staphylococcus aureus (10.7%), and Streptococcus pneumoniae (9.7%). Only 8/194 (4.1%) blood cultures returned positive. Median duration of intravenous antibiotics was 4 days and median total duration was 17 days. The most common empiric regimen prescribed was ceftriaxone and clindamycin (64.1%). Despite low incidence of methicillin-resistant S aureus, empiric antibiotics often consisted of 2 antibiotics to ensure coverage for this bacterium.

Difference in microbiome compositions of healthy peri-implant sulcus and peri-implantitis sulcus from the same patient

ObjectiveThe objective of this study is to compare the microbiome of healthy peri-implant sulcus (C) and peri-implantitis sulcus (U) from the same patient and analyze the difference in the microbiome composition. Materials and methodsDNA samples of subgingival biofilms from 10 C (control group) and 10 U (uncontrolled group) sites were sent to Microbiome Center in Korea Research Institute of Biomedical Science and analyzed using 16s rRNA gene amplification and sequencing (MiSeq, Illumina) and human oral microbiome database (HOMD). ResultsAt the phylum level, Firmicutes and Proteobacteria were more abundant in group C, while Firmicutes and Bacteroidetes were dominant in group U. At the genus level, the core peri-implant microbiome was Streptococcus in group C. On the other hand, the core peri-implant microbiome was Porphyromonas, especially P. gingivalis in group U. ConclusionIn this study, the microbiome composition of peri-implantitis sulcus was different from that of healthy peri-implant sulcus from the same patient. The peri-implantitis microbiome was pathogen-enriched and was similar to the microbiome associated with periodontitis.

Vancomycin coupled chitosan/PEO nanofibrous scaffold with the desired antibacterial activity as a potential for biomedical application

This study aims to evaluate the Vancomycin (VCM) combination with Chitosan (CS)/ Polyethylene oxide (PEO) nanofibers’ intrinsic antibacterial properties causing a synergistic effect against possible serious bacterial infections (PSBI). VCM/CS nanofiber scaffold was fabricated using the electrospinning method. Characterizations are performed by Fourier transform infrared (FT-IR) to examine the functional groups of each compound, scanning electron microscopy (SEM), and transient electron microscopy (TEM) to evaluate nanofiber diameter and structure. Antibacterial activities of the nanofibrous scaffold were assessed against bacterial strains, including standard Staphylococcus aureus ( S. aureus), VCM-sensitive Enterococcus (VSE), methicillin-resistant S. aureus (MRSA), VCM-resistant Enterococcus (VRE), and Streptococcus group A by microdilution broth methods. The FT-IR, SEM, and TEM examination results confirm the CS/PEO nanofiber scaffold fabrication. The antibacterial examination results showed no significant difference between the minimum inhibitory concentration (MIC) values of VCM and with MIC of VCM/CS nanofibers. Still, there were significant differences between the MIC of CS and VCM/CS nanofibers in S. aureus, but this is not more significant than VCM. This study illustrated that VCM coupled to CS nanofibers had acceptable antibacterial activity against the Gram-positive bacterium. This work motivated researchers’ insight into nanostructures’ potential accompanied by antibacterial polymer and antibiotics synergistic effects against PSBI.

Aggressive abscesses in the head and neck region of probable odontogenic origin – two case reports

Odontogenic infections are the most common type of infections of the head and neck among adults. They usually spread continuously from the mandible and/or maxilla into the sublingual, submandibular or masticatory spaces, then directly into the parapharyngeal space. They require comprehensive diagnostic and therapeutic management, as they may potentially lead to life-threatening complications. We present two clinical manifestations of aggressive abscesses in the head and neck region of probable odontogenic origin and discuss different therapeutic approaches. The first patient, a 31-year-old man, was admitted because of a tumor-like lesion within the right maxillary sinus. He complained of purulent nasal discharge of two weeks duration despite antibiotic therapy. In the Caldwell-Luc operation a cyst filled with puss was displayed, the sac of the cyst and the polypoid mass were removed. The second patient, a 28-year-old man, was admitted due to an abscess of the left half of the neck and viscerocranium, with a large edema of this area, neck pain, fever, dyspnea and lockjaw. The patient was qualified for surgery. During intubation, a purulent collection emptied into the oral cavity and throat. In both cases, simultaneously with the surgery, an empirical broad-spectrum antibiotic therapy was administered. Microbiological analysis of the material collected during the operations revealed Prevotella melaninogenica in the first case, and Streptococcus group C in the second. Treatment of aggressive odontogenic infections must take a comprehensive approach, including both surgical intervention and antibiotic therapy covering Gram-positive as well as Gram-negative aerobic and anaerobic pathogens.

P-340 Endometrial microbiome - is every dysbiosis an inflammation?

Abstract Study question The endometrial microbiome, in addition to other parameters of inflammation (CD138 presence, NK bright fraction presence), may be a complementary marker of ongoing local inflammation. Summary answer Presented results of the microbiome in comparison with the CD 138 marker may indicate inflammation in the endometrium, which is caused by dysbiosis. What is known already The study of the microbiome and the assessment of its impact on female reproductive system on embryo implantation, pregnancy maintenance and the success of the in vitro fertilization (IVF) procedure is an increasingly popular research topic. The protective role of Lactobacillus (other than L.iners) is known, and probably its low number may be related to the impossibility of embryo implantation. Dysfunctional mycobiome may be the cause of chronic inflammation of the endometrium, including endometriosis and recurrent implantation failures. Importantly, the dysbiotic profile of the endometrial microflora often does not cause any clinical symptoms. Study design, size, duration The clinical study included 182 women in child-bearing age, who were patients of the Gyncentrum Clinic (Poland), and who were qualified for the IVF procedure. In this group of patients, 201 samples combined were tested, obtaining 19 negative results due to the low quality of swabs, and the small amount of microbiota impossible to efficiently isolate. In the study, samples were analysed from January to December 2022 collection. Participants/materials, setting, methods To analyze the assumed parameters, patients treated at the Gyncentrum Clinic underwent a routine hysteroscopy procedure, during which endometrial swabs (determination of the molecular microbiome using the Next Generation Sequencing NGS method) and tissue fragments (determination of CD138 immunohistochemically and NK fractions by flow cytometry) were collected. Nucleic acids were isolated from the swabs for the preparation of libraries, based on the Illumina-16S Metagenomic Sequencing Library Preparation. Main results and the role of chance The microbiome study and other inflammation parameters in the group of our patients allowed us to observe some trends. Due to the microbiological endometrium profile, the patients were divided into 3 groups: 1) normal microflora (domination of Lactobacillus other than L.iners and/or Bifidobacterium;n =135), 2) moderate dysbiosis (presence of Lactobacillus and/or Bifidobacterium and/or L. iners-max. 50 % of all sample- and also other potentially harmful species e.g. Enterobacteriaceae group, Streptococcus group, Veilonella;n =28); 3) dysbiosis (with/without low number of Lactobacillus and Bifidobacterium, strong dominance of harmful species listed above or L.iners dominance;n =19). We observed that in the group of endometrial dysbiosis patients, an increased CD138 index ( ⩾1/10 high power fields HPF) is more often noted - in the group of dysbiotic patients with CD138 = 0/10 HPF 7.21 %, in the group of dysbiotic patients with increased CD 138 15.49 %. We didn `t notice any trends comparing the results of CD138 to the NK bright fraction (CD56 + +/CD16-) tested in endometrial specimens, or the relationship of this fraction to the microbiome. Observed trend indicates a certain relationship in the presence of abnormal microflora and inflammation expressed by CD138, but it requires confirmation on a larger study group and obtain information about the success of pregnancy. Limitations, reasons for caution The conducted research require broader analysis on a larger group of patients. It is necessary to obtain full information about the success of pregnancy in all analyzed patients. Identification of taxa using the NGS method is not the same as the identification of microorganisms living in the studied microenvironment. Wider implications of the findings Presented results should be treated as a starting point for further analyses, important in the context of research based on infertility, focusing on relationships between the microbiome and the IVF effectiveness. It seems interesting to extend the molecular study of the microbiome to its other elements - viruses, fungi, protozoa. Trial registration number 161/KBL/OIL/2021 Study funding No Funding source Funding by hospital/clinic(s)

P-340 Endometrial microbiome - is every dysbiosis an inflammation?

Abstract Study question The endometrial microbiome, in addition to other parameters of inflammation (CD138 presence, NK bright fraction presence), may be a complementary marker of ongoing local inflammation. Summary answer Presented results of the microbiome in comparison with the CD 138 marker may indicate inflammation in the endometrium, which is caused by dysbiosis. What is known already The study of the microbiome and the assessment of its impact on female reproductive system on embryo implantation, pregnancy maintenance and the success of the in vitro fertilization (IVF) procedure is an increasingly popular research topic. The protective role of Lactobacillus (other than L.iners) is known, and probably its low number may be related to the impossibility of embryo implantation. Dysfunctional mycobiome may be the cause of chronic inflammation of the endometrium, including endometriosis and recurrent implantation failures. Importantly, the dysbiotic profile of the endometrial microflora often does not cause any clinical symptoms. Study design, size, duration The clinical study included 182 women in child-bearing age, who were patients of the Gyncentrum Clinic (Poland), and who were qualified for the IVF procedure. In this group of patients, 201 samples combined were tested, obtaining 19 negative results due to the low quality of swabs, and the small amount of microbiota impossible to efficiently isolate. In the study, samples were analysed from January to December 2022 collection. Participants/materials, setting, methods To analyze the assumed parameters, patients treated at the Gyncentrum Clinic underwent a routine hysteroscopy procedure, during which endometrial swabs (determination of the molecular microbiome using the Next Generation Sequencing NGS method) and tissue fragments (determination of CD138 immunohistochemically and NK fractions by flow cytometry) were collected. Nucleic acids were isolated from the swabs for the preparation of libraries, based on the Illumina-16S Metagenomic Sequencing Library Preparation. Main results and the role of chance The microbiome study and other inflammation parameters in the group of our patients allowed us to observe some trends. Due to the microbiological endometrium profile, the patients were divided into 3 groups: 1) normal microflora (domination of Lactobacillus other than L.iners and/or Bifidobacterium; n = 135), 2) moderate dysbiosis (presence of Lactobacillus and/or Bifidobacterium and/or L. iners-max. 50% of all sample- and also other potentially harmful species e.g. Enterobacteriaceae group, Streptococcus group, Veilonella; n = 28); 3) dysbiosis (with/ without low number of Lactobacillus and Bifidobacterium, strong dominance of harmful species listed above or L.iners dominance; n = 19). We observed that in the group of endometrial dysbiosis patients, an increased CD138 index (⩾1/10 high power fields HPF) is more often noted - in the group of dysbiotic patients with CD138 = 0/10 HPF 7.21%, in the group of dysbiotic patients with increased CD 138 15.49%. We didn`t notice any trends comparing the results of CD138 to the NK bright fraction (CD56 ++/CD16-) tested in endometrial specimens, or the relationship of this fraction to the microbiome. Observed trend indicates a certain relationship in the presence of abnormal microflora and inflammation expressed by CD138, but it requires confirmation on a larger study group and obtain information about the success of pregnancy. Limitations, reasons for caution The conducted research require broader analysis on a larger group of patients. It is necessary to obtain full information about the success of pregnancy in all analyzed patients. Identification of taxa using the NGS method is not the same as the identification of microorganisms living in the studied microenvironment. Wider implications of the findings Presented results should be treated as a starting point for further analyses, important in the context of research based on infertility, focusing on relationships between the microbiome and the IVF effectiveness. It seems interesting to extend the molecular study of the microbiome to its other elements - viruses, fungi, protozoa. Trial registration number 161/KBL/OIL/2021

Nutritionally Variant Streptococci - Its Clinical Relevance and Treatment Options: A Mini-Review

: Nutritionally variant streptococci (NVS) were assumed to be nutritional mutants of the viridans group of streptococci, but they are now considered as other Streptococcus species. Due to their difficult nature, to date, the detection and treatment of NVS are challenging. : This review aims at a compilation of a comprehensive study on literature reporting the microbiological characteristics of NVS species, their detection, and treatment strategies with an emphasis on large-scale research experimentations. : According to the literature, the classification of these Streptococci has changed several times, interpreting the scientific literature of Abiotrophia and Granulicatella spp. NVS strains exhibit pleomorphic cellular morphologies, and they can be distinguished from other streptococci by their biochemical reactions and molecular tests. They have been isolated from clinical specimens including pus, synovial fluid, and blood, in addition to their involvement in endocarditis. Treatment of NVS is challenging due to its difficult nature and the complexity of antimicrobial susceptibility testing. : Early diagnosis is critical for initiating proper therapy and avoiding fatal consequences. Microbiologists and clinicians ought to be cautious of these isolates, which are easy to overlook due to their difficult nature and the challenges in retrieving from clinical samples. Hence largescale research is required to identify additional detection techniques, infrastructure, and treatment options.

Streptococcus cristatus bacteremia in a patient with poor oral hygiene: a case report

BackgroundStreptococcus cristatus is a member of the Mitis streptococcus group. Like other members of this group, it resides on mucosal surfaces of the oral cavity. However, little is known about its ability to cause disease as there are only a handful of cases in the literature. Two of these cases involved infective endocarditis with significant complications. However, these cases involved additional microbes, limiting the inferences about the pathogenicity of Streptococcus cristatus.Case presentationA 59-year-old African American male with end-stage cryptogenic cirrhosis and ascites presented with fatigue and confusion. A paracentesis was negative for spontaneous bacterial peritonitis, but two separate blood cultures grew Streptococcus cristatus. Our patient had a history of dental caries and poor oral hygiene, which were likely the source of the infection. Echocardiograms revealed new aortic regurgitation, indicating “possible endocarditis” per the Modified Duke Criteria. However, since his clinical picture and cardiac function were reassuring, we elected against treatment for infective endocarditis. He was treated for bacteremia with a 2-week course of cephalosporins consisting of 8 days of ceftriaxone, transitioning to cefpodoxime after discharge. Despite having end-stage liver disease, our patient did not experience any significant complications from the infection.ConclusionA patient with end-stage cirrhosis and poor oral hygiene developed bacteremia with an oral bacterium called Streptococcus cristatus. Unlike previous cases in literature, our patient did not meet criteria for a definitive diagnosis of infective endocarditis, and he experienced no other complications from the infection. This suggests coinfectants may have been primarily responsible for the severe cardiac sequelae in prior cases, whereas isolated Streptococcus cristatus infection may be relatively mild.

Correlation Betveen Erythromycin- Resistance Phenotypes ofStreptoco cc us Pne unrc nifi e ancl the Invitro Activitl' of Telith romycineand Azithrornycine

Tow principal mechanisms have so far been found to be responsible for acquired macrolide ,lincosamide and streptogramin B (MLSB) antibiotics resistance in Streptococcus pneumoniae : target site modification and active drug efflux .the target site modification is due to methylase prevents the binding of the antibiotic to its ribosomal target and can be expressed either in a constitutive (cMLS phenotype) or inducible (iMLS phenotype ) manner .the macrolide efflux system,M phenotype ,is mediated by a membrane protein responsible for the efflux resistance. Although the incidence of resistance to macrolides was low in the past today the incidence reported by several countries shows a sensible increase. Thus it is necessary to search and test novel antimicrobial agents characterized by a spectrum of activity against the most common respiratory pathogens. This study compared the invitro activity (MIC and MBC) of telithromycin with activity of azithromycin against Streptococcus pneumoniae recently isolated from San Giovanni Battista Hospital (Turin, Italy). Erythromycin — resistance phenotypes were determined through a triple — disk test to correlate a potential different bacterial pattern to antimicrobial s sceptibility. The incidence of erythromycin-resistance was 26.66% .In the group of Ery-R Streptococcus pneumoniae 58.33% strains belonged to ¢MLS phenotype, 33.33% to M phenotype and 8.33% to iMLS phenotype. Telithromycin presented MIC values lower than those detected with azithromycin against all isolated strains . Telithromycin appeared to be highly active against Streptococcus pneumoniae, in particular when resistance is mediated by the efflux system confirming its clinical efficacy among respiratory streptococcal infections.

Molecular Characterization of Some Bacillus Species from Vegetables and Evaluation of Their Antimicrobial and Antibiotic Potency.

Numerous natural habitats, such as soil, air, fermented foods, and human stomachs, are home to different Bacillus strains. Some Bacillus strains have a distinctive predominance and are widely recognized among other microbial communities, as a result of their varied habitation and physiologically active metabolites. The present study collected vegetable products (potato, carrot, and tomato) from local markets in Almaty, Kazakhstan. The bacterial isolates were identified using biochemical and phylogenetic analyses after culturing. Our phylogenetic analysis revealed three Gram-positive bacterial isolates BSS11, BSS17, and BSS19 showing 99% nucleotide sequence similarities with Bacillus subtilis O-3, Bacillus subtilis Md1-42, and Bacillus subtilis Khozestan2. The crude extract was prepared from bacterial isolates to assess the antibiotic resistance potency and the antimicrobial potential against various targeted multidrug-resistant strains, including Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus group B, Streptococcus mutans, Candida albicans, Candida krusei, Pseudomonas aeruginosa, Shigella sonnei, Klebsiella pneumoniae, Salmonella enteritidis, Klebsiella aerogenes, Enterococcus hirae, Escherichia coli, Serratia marcescens, and Proteus vulgaris. This study found that the species that were identified have the ability to produce antibiotic chemicals. Additionally, the GC-MS analysis of three bacterial extracts revealed the presence of many antibiotic substances including phenol, benzoic acid, 1,2-benzenedicarboxylic acid and bis(2-methylpropyl), methoxyphenyl-oxime, and benzaldehyde. This work sheds light on the potential of Bacillus to be employed as an antimicrobial agent to target different multidrug-resistant bacterial strains. The results indicate that market vegetables may be a useful source of strains displaying a range of advantageous characteristics that can be used in the creation of biological antibiotics.

Genomic Analysis Reveals New Integrative Conjugal Elements and Transposons in GBS Conferring Antimicrobial Resistance.

Streptococcus agalactiae or group B streptococcus (GBS) is a leading cause of neonatal sepsis and increasingly found as an invasive pathogen in older patient populations. Beta-lactam antibiotics remain the most effective therapeutic with resistance rarely reported, while the majority of GBS isolates carry the tetracycline resistance gene tet(M) in fixed genomic positions amongst five predominant clonal clades. In the UK, GBS resistance to clindamycin and erythromycin has increased from 3% in 1991 to 11.9% (clindamycin) and 20.2% (erythromycin), as reported in this study. Here, a systematic investigation of antimicrobial resistance genomic content sought to fully characterise the associated mobile genetic elements within phenotypically resistant GBS isolates from 193 invasive and non-invasive infections of UK adult patients collected during 2014 and 2015. Resistance to erythromycin and clindamycin was mediated by erm(A) (16/193, 8.2%), erm(B) (16/193, 8.2%), mef(A)/msr(D) (10/193, 5.1%), lsa(C) (3/193, 1.5%), lnu(C) (1/193, 0.5%), and erm(T) (1/193, 0.5%) genes. The integrative conjugative elements (ICEs) carrying these genes were occasionally found in combination with high gentamicin resistance mediating genes aac(6')-aph(2″), aminoglycoside resistance genes (ant(6-Ia), aph(3'-III), and/or aad(E)), alternative tetracycline resistance genes (tet(O) and tet(S)), and/or chloramphenicol resistance gene cat(Q), mediating resistance to multiple classes of antibiotics. This study provides evidence of the retention of previously reported ICESag37 (n = 4), ICESag236 (n = 2), and ICESpy009 (n = 3), as well as the definition of sixteen novel ICEs and three novel transposons within the GBS lineage, with no evidence of horizontal transfer.

Incidence and clinical and microbiological features of invasive and probable invasive streptococcal group A infections in children and adults in the Brussels-Capital Region, 2005–2020

Assess the incidence, risk factors, clinical and microbiological features, and outcome of both probable invasive and invasive group A Streptococcus (GAS) infections in children and adults in the BrusselsCapital Region between 2005 and 2020. A retrospective, multicentric study was performed in three university hospitals in Brussels. Patients were identified through the centralized laboratory information system. Epidemiological and clinical data were collected from patients' hospital records. A total of 467 cases were identified. Incidence has increased from 2.1 to 10.9/100,000 inhabitants between 2009 and 2019 in non-homeless adults while it was above 100/100,000 on homeless in years with available denominators. Most of GAS were isolated from blood (43.6%), and the most common clinical presentation was skin and soft tissue infections (42.8%). A third of all the patients needed surgery, a quarter was admitted to the intensive care unit, and 10% of the adult patients died. Wounds and chickenpox disease were the main risk factors for children. Tobacco, alcohol abuse, wounds or chronic skin lesion, being homeless, and diabetes were identified as major predisposing factors for adults. The most common emm clusters were D4, E4, and AC3; 64% of the isolates were theoretically covered by the 30-valent M-protein vaccine. The burden of invasive and probable invasive GAS infections is on the rise in the studied adult population. We identified potential interventions that could contribute to decrease this burden: appropriate care of wounds, specifically among homeless and patients with risk factors such as diabetes and systematic chickenpox vaccination for children.

An oral pH-responsive Streptococcus agalactiae vaccine formulation provides protective immunity to pathogen challenge in tilapia: A proof-of-concept study.

Intensive tilapia farming has contributed significantly to food security as well as to the emergence of novel pathogens. This includes Streptococcus agalactiae or Group B Streptococcus (GBS) sequence type (ST) 283, which caused the first known outbreak of foodborne GBS illness in humans. An oral, easy-to-administer fish vaccine is needed to reduce losses in fish production and the risk of zoonotic transmission associated with GBS. We conducted a proof-of-concept study to develop an oral vaccine formulation that would only release its vaccine cargo at the site of action, i.e., in the fish gastrointestinal tract, and to evaluate whether it provided protection from experimental challenge with GBS. Formalin-inactivated S. agalactiae ST283, was entrapped within microparticles of Eudragit® E100 polymer using a double-emulsification solvent evaporation method. Exposure to an acidic medium simulating the environment in tilapia stomach showed that the size of the vaccine-loaded microparticles decreased rapidly, reflecting microparticle erosion and release of the vaccine cargo. In vivo studies in tilapia showed that oral administration of vaccine-loaded microparticles to fish provided significant protection from subsequent homologous pathogen challenge with GBS ST283 by immersion compared to the control groups which received blank microparticles or buffer, reducing mortality from 70% to 20%. The high efficacy shows the promise of the vaccine platform developed herein, which might be adapted for other bacterial pathogens and other fish species.

Prevalence, Antibiotic Susceptibility Profile and Associated Factors of Group A Streptococcal pharyngitis Among Pediatric Patients with Acute Pharyngitis in Gondar, Northwest Ethiopia.

Streptococcus pyogenes (S. pyogenes) or group A streptococcus is a common cause of bacterial pharyngitis in children. Since it is difficult to distinguish between viral and bacterial pharyngitis using solely signs and symptoms, culture-based diagnosis and treatment are critical for avoiding serious complications. Therefore, this study aimed to determine the prevalence, antimicrobial susceptibility patterns, and associated factors of S. pyogenes among pediatric patients with acute pharyngitis. A hospital-based cross-sectional study was conducted at the University of Gondar Comprehensive Specialized Hospital from April to June 2021. Standard microbiological procedures were used to collect and process throat swabs and to isolate and identify S. pyogenes. The disc diffusion method was used for antimicrobial susceptibility testing (AST). A total of 215 children with acute pharyngitis were included in this study. Of these, 23 (10.7%) were culture positive for S. pyogenes. The presence of an inflamed tonsil, tonsillar exudate, scalariform rash, and dysphagia were associated with streptococcal pharyngitis. Children aged 5 to 15 were more susceptible to streptococcal throat infection than younger children. Penicillin, vancomycin, chloramphenicol, clindamycin, and ceftriaxone were effective against 100%, 95.7%, 95.7%, 91%, and 87% of isolates, respectively. In contrast, 56.5%, 39.1%, and 30.4% of isolates showed at least reduced susceptibility to tetracycline, erythromycin, and azithromycin, respectively. Streptococcus pyogenes is responsible for 10.7% of acute pharyngitis cases among pediatric patients in the study area. Although all isolates remain sensitive to penicillin, many showed reduced susceptibility to tetracycline and macrolides. Therefore, prior to antibiotic prescription, screening children with acute pharyngitis for S. pyogenes and testing the antibiotic susceptibility of isolates is recommended.

Chemical composition and biological activities of Jamaican Cannabis sativa essential oils as the plant matures

AbstractCannabis sativa is a flowering plant belonging to the Cannabinaceae family. There have been numerous ongoing studies globally on C. sativa which include investigating the yield and quality of essential oils. However, this study is the first to assess the chemical composition and biological activities of Jamaican C. sativa essential oils (EOs) extracted via hydrodistillation as the plants mature from week 8 through to week 12. EOs from fresh landrace female plants were analysed by gas chromatography–mass spectrometry (GC–MS) and GC coupled to a flame ionization detector (GC‐FID). Cannabis sativa essential oils were screened for their in vitro antimicrobial activity using the disc diffusion method and further with tube dilution method. The antioxidant properties were investigated using the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging assay. In total, 36 constituents were identified in the C. sativa EOs by comparison of the Kováts retention indices (RI), the mass spectra data with those in the Natural Institute of Standards and Technology (NIST) library and by co‐elution with authentic samples where available. The major constituents were β‐caryophyllene (25.34%) and α‐humulene (α‐caryophyllene) (10.94%) both at the highest levels in week nine and were the most abundant constituents present at all stages of maturity. All extracted C. sativa essential oils did not exhibit antioxidant properties. However, the C. sativa essential oils exhibit significant to moderate antimicrobial property against the test gram‐positive microorganisms, Enterococcus faecalis, Streptococcus Group A and Streptococcus Group B with MIC values ranging from 16 to 125 μg/mL.

Streptolysin O Deficiency in Streptococcus pyogenes M1T1 covR/S Mutant Strain Attenuates Virulence in In Vitro and In Vivo Infection Models.

Mutation within the Streptococcus pyogenes (Streptococcus group A; Strep A) covR/S regulatory system has been associated with a hypervirulent phenotype resulting from the upregulation of several virulence factors, including the pore-forming toxin, streptolysin O (SLO). In this study, we utilized a range of covR/S mutants, including M1T1 clonal strains (5448 and a covS mutant generated through mouse passage designated 5448AP), to investigate the contribution of SLO to the pathogenesis of covR/S mutant Strep A disease. Up-regulation of slo in 5448AP resulted in increased SLO-mediated hemolysis, decreased dendritic cell (DC) viability post coculture with Strep A, and increased production of tumor necrosis factor (TNF) and monocyte chemoattractant protein 1 (MCP-1) by DCs. Mouse passage of an isogenic 5448 slo-deletion mutant resulted in recovery of several covR/S mutants within the 5448Δslo background. Passage also introduced mutations in non-covR/S genes, but these were considered to have no impact on virulence. Although slo-deficient mutants exhibited the characteristic covR/S-controlled virulence factor upregulation, these mutants caused increased DC viability with reduced inflammatory cytokine production by infected DCs. In vivo, slo expression correlated with decreased DC numbers in infected murine skin and significant bacteremia by 3 days postinfection, with severe pathology at the infection site. Conversely, the absence of slo in the infecting strain (covR/S mutant or wild-type) resulted in detection of DCs in the skin and attenuated virulence in a murine model of pyoderma. slo-sufficient and -deficient covR/S mutants were susceptible to immune clearance mediated by a combination vaccine consisting of a conserved M protein peptide and a peptide from the CXC chemokine protease SpyCEP. IMPORTANCE Streptococcus pyogenes is responsible for significant numbers of invasive and noninvasive infections which cause significant morbidity and mortality globally. Strep A isolates with mutations in the covR/S system display greater propensity to cause severe invasive diseases, which are responsible for more than 163,000 deaths each year. This is due to the upregulation of virulence factors, including the pore-forming toxin streptolysin O. Utilizing covR/S and slo-knockout mutants, we investigated the role of SLO in virulence. We found that SLO alters interactions with host cell populations and increases Strep A viability at sterile sites of the host, such as the blood, and that its absence results in significantly less virulence. This work underscores the importance of SLO in Strep A virulence while highlighting the complex nature of Strep A pathogenesis. This improved insight into host-pathogen interactions will enable a better understanding of host immune evasion mechanisms and inform streptococcal vaccine development programs.

Septicemia and meningitis caused by group A streptococcus: A case report and literature review

The invasive diseases due to Streptococcus pyogenes are pretty rare infections especially in pediatrics. We present to you a case of a 13-year-old who was admitted in pediatric’s intensive care for a polytrauma, on his 4th day of hospitalization he developed a fever for which he had a cytobacteriological assay of the spinal fluid who was in favor of a bacterial meningitis with 61 white cells predominantly neutrophilic 81% and a positive direct examination and culture after 24-hour incubation. The blood cultures from 3 sets (5 bottles) were also positive after 24h incubation and all pointed out to β hemolytic colonies in favor of streptococcus that was identified afterwards with serogrouping and on an automaton proving the incrimination of streptococcus group A. A review of literature was then conducted to enlighten clinicians on this unusual but equally dangerous bacteria.

Clinical case of isolation and identification of <I>Streptococcus equi subsp. Zooepidemicus</I>

Streptococci manifest their pathogenic properties by reducing the overall resistance of the organism or individual tissues.Purpose of the work: isolation, identification and study of the biological properties of isolates isolated from the foal.A pure culture was obtained, morphological, cultural and biochemical properties were studied.For the subsequent identification of streptococci to species, two api 20 Strep test systems (BIOMERIEUX, France) were used. To determine the serological group of streptococci, a latex agglutination test was used using a kit for diagnosing streptococci of groups A, B, C, D, F, and G (OXOID, UK).Laboratory methods of diagnostics for the identification of causative agents of streptococcosis and their species differentiation have been studied. Virulent Streptococcus equi subsp. zooepidemicus caused abscesses in the area of the elbow joint of the foal. Isolation of bacterial cultures was carried out by the bacteriological method. Isolated Streptococcus equi subsp. zooepidemicus had the fermentation of a number of carbohydrates: sorbitol, there was no splitting of lactose, tregolose. Streptococcus equi subsp. zooepidemicus hydrolyzed esculin, no D-ribose fermentation was noted. However, the fermentation of carbohydrates is not a stable and clear sign, therefore it is not used for differentiation and identification of streptococci.When inoculated on blood agar with 5% sheep blood after cultivation for 24 hours at 37 0C, small gray-white colonies were found, surrounded by a wide transparent zone of beta-hemolysis. Catalase test is negative.As a result, it was found that the isolated culture belongs to the species Streptococcus equi subsp. zooepidemicus belonging to group C according to Lancefield.Modern laboratory diagnostics requires an integrated approach to identification, which includes bacteriological and serological methods - polyphase analysis. When identifying streptococci, the determination of their serological group according to Lancefield is of great importance. For this purpose, a latex agglutination reaction is convenient using a kit for diagnosing streptococci of groups A, B, C, D, F and G (OXOID, UK), coagglutination "Streptotest A, B, C, D, G" (AQUAPAST).

Molecular Epidemiology of Group B Streptococcus Colonization in Egyptian Women.

(1) Background: Streptococcus agalactiae or Group B Streptococcus (GBS) causes severe neonatal infections with a high burden of disease, especially in Africa. Maternal vaginal colonization and perinatal transmissions represent the common mode of acquiring the infection. Development of an effective maternal vaccine against GBS relies on molecular surveillance of the maternal GBS population to better understand the global distribution of GBS clones and serotypes. (2) Methods: Here, we present genomic data from a collection of colonizing GBS strains from Ismailia, Egypt that were sequenced and characterized within the global JUNO project. (3) Results: A large proportion of serotype VI, ST14 strains was discovered, a serotype which is rarely found in strain collections from the US and Europe and typically not included in the current vaccine formulations. (4) Conclusions: The molecular epidemiology of these strains clearly points to the African origin with the detection of several sequence types (STs) that have only been observed in Africa. Our data underline the importance of continuous molecular surveillance of the GBS population for future vaccine implementations.

ОСОБЕННОСТИ ТЕЧЕНИЯ ОСТРЫХ ОДОНТОГЕННЫХ ВОСПАЛИТЕЛЬНЫХ ПРОЦЕССОВ ЧЕЛЮСТЕЙ ВДЕТСКОМ ВОЗРАСТЕ

The goal.Studying the clinical course’s features of acute odontogenic inflammatory processes of the jaws in children, describing species composition of pathogens, determination sensitivity to antibiotics of various groups in acute odontogenic inflammatory processes of the jaws in childhood. Materials and methods.The case histories of 900 patients were analyzed, microbiological research methods were carried out (microscopic examination of clinical samples with Gram staining, culture method, determination of the sensitivity of theisolated pathogen to antimicrobial drugs).Results.The most common odontogenic inflammatory processes of the jaws were observed in children aged 4–5 years. In48,85 % of cases in a milk bite and in 67,92 % of cases in a permanent bite, the cause of the development of an odontogenic inflammatory process was complicated caries of the mandibular molars. 56% of children had a general condition. The leading causative agent of the inflammatory process of the jaws was in 65,6 % of cases hemolytic streptococcus. In other cases, Streptococcus Viridans(6,1 %), pneumococci (4,3 %), candida (3 %), Staphylococcus aureus(2,8 %), Moraxella cataralis(1,2 %), etc. were detected in the mixed microflora of purulent exudate. The drugs of choice for empirical antibiotic therapy for odontogenic inflammatory process caused by beta-hemolytic streptococcus group A are vancomycin (antibiotic sensitivity –99 %), fluoroquinolones (antibiotic sensitivity –98 %), beta-lactams (antibiotic sensitivity –91 %). The highest percentage of resistance of this microflora was noted to macrolides (41 %), and to clindamycin (33 %). The rapid spread of the purulent-inflammatory process in the maxillofacial region in acute odontogenic processes in children, the resistant microflora of the odontogenic purulent focus require a competent approach when providing emergency care.Conclusions.The obtained has great practical importance for the choice of rational antibiotic therapy.