Metagenomic analysis of fecal samples in colorectal cancer Egyptians patients post colectomy: A pilot study.

One of the most prevalent malignancies that significantly affects world health is colorectal cancer (CRC). While genetics are involved in a portion of CRC patients, most cases are sporadic. The microbiome composition could be a new source of tumor initiation and progression. This research was conducted to investigate the microbiota composition of CRC patients post colectomy at taxonomic and functional levels. Using a next-generation sequencing approach, using an Illumina Novaseq 6000, the fecal samples of 13 patients were analyzed and the obtained data was subjected to a bioinformatics analysis. The bacterial abundance and uniqueness varied in CRC patients alongside differences in bacterial counts between patients. Bacteroides fragilis, Bacteroides vulgatus, Escherichia coli, and Fusobacterium nucleatum were among the pro-cancerous microorganisms found. Concurrently, bacteria linked to CRC progression were detected that have been previously linked to metastasis and recurrence. At the same time, probiotic bacteria such as Bifidobacterium dentium, Bifidobacterium bifidum, and Akkermansia muciniphila increased in abundance after colectomies. Additionally, numerous pathways were deferentially enriched in CRC, which emerged from functional pathways based on bacterial shotgun data. CRC-specific microbiome signatures include an altered bacterial composition. Our research showed that microbial biomarkers could be more usefully employed to explore the link between gut microbiota and CRC using metagenomic techniques in the diagnosis, prognosis, and remission of CRC, thereby opening new avenues for CRC treatment.

Multi-omics analysis of fecal samples in colorectal cancer Egyptians patients: a pilot study.

BACKGROUND: Colorectal cancer (CRC) is a public health concern and the second most common disease worldwide. This is due to genetic coding and is influenced by environmental aspects, in which the gut microbiota plays a significant role. The purpose of this study was to compare the microbiota makeup of CRC patients with that of healthy control and to identify upregulated and downregulated proteins and metabolites in CRC patients. Using a next-generation sequencing approach, fecal samples of five females (4 CRC patients and one healthy control) were analyzed by BGI DNBSEQ-T7, Hong Kong, China. Furthermore, proteomics and metabolomics analysis were performed using LC-MS/MS technique. RESULTS: Dysbiosis of gut microbiota has been observed in patients with CRC, with an increase in microbiota diversity at all taxonomic levels relative to healthy control. Where, at the functional level the bacterial species participate in many different pathways among them de novo nucleotide synthesis and amino acids pathways were aberrantly upregulated in CRC patients. Proteomics and metabolomics profiles of CRC patients showed different proteins and metabolites, a total of 360 and 158 proteins and metabolites, respectively were highly expressed compared to healthy control with fold change ≥ 1.2. Among the highly expressed proteins were transketolase, sushi domain-containing protein, sulfide quinone oxidoreductase protein, AAA family ATPase protein, carbonic anhydrase, IgG Fc-binding protein, nucleoside diphosphate kinase protein, arylsulfatase, alkaline phosphatase protein, phosphoglycerate kinase, protein kinase domain-containing protein, non-specific serine/threonine protein kinase, Acyl-CoA synthetase and EF-hand domain-containing protein. Some of the differential metabolites, Taurine, Taurocholic acid, 7-ketodeoxycholic acid, Glycochenodeoxycholic acid, Glycocholic acid, and Taurochenodeoxycholic acid that belong to bile acids metabolites. CONCLUSIONS: Some bacterial species, proteins, and metabolites could be used as diagnostic biomarkers for CRC. Our study paves an insight into using multi-omics technology to address the relationship between gut microbiota and CRC.

The Eradication of Helicobacter pylori Was Significantly Associated with Compositional Patterns of Orointestinal Axis Microbiota.

BACKGROUND: Helicobacter pylori (H. pylori) is significantly linked to various diseases that seriously impact human health, such as gastric ulcers, chronic gastritis and gastric adenocarcinoma. METHODS: The compositional shifts in bacterial communities of the orointestinal axis were surveyed pre/post-eradication of H. pylori. In total, 60 samples, including stool and salivary specimens, were collected from 15 H. pylori-positive individuals (HPP) before beginning and 2 months after receiving the eradication therapy. The V3-V4 regions of the 16S rRNA gene were sequenced using MiSeq. RESULTS: Overall, oral microbiomes were collectively more diverse than the gut microbiomes (Kruskal-Wallis; p = 3.69 × 10-5). Notably, the eradication of H. pylori was associated with a significant reduction in the bacterial diversity along the orointestinal axis (Wilcoxon rank sum test; p = 6.38 × 10-3). Interestingly, the oral microbiome of HPP showed a positive correlation between Proteobacteria and Fusobacteria, in addition to a significant predominance of Streptococcus, in addition to Eubacterium_eligens, Haemophilus, Ruminococcaceae, Actinomyces and Staphylococcus. On the other hand, Fusobacterium, Veillonella, Catenibacterium, Neisseria and Prevotella were significantly enriched upon eradication of H. pylori. Generally, Bacteroidetes and Fusobacteria positively coexisted during H. pylori infection along the orointestinal axis (r = 0.67; p = 0.0006). The eradication of H. pylori was positively linked to two distinctive orotypes (O3 and O4). Orotype O4 was characterized by a robust abundance of Veillonella and Fusobacteria. The gut microbiomes during H. pylori infection showed a remarkable predominance of Clostridium_sensu_stricto_1 and Escherichia_Shigella. Likewise, Bifidobacterium and Faecalibacterium were significantly enriched upon eradication of H. pylori. CONCLUSIONS: Finally, the impact of eradication therapy clearly existed on the representation of certain genera, especially in the oral microbiome, which requires particular concern in order to counteract and limit their subsequent threats.

Compositional Changes in the Vaginal Bacterial Microbiome of Healthy Pregnant Women across the Three Gestational Trimesters in Ismailia, Egypt.

The composition of the vaginal microbiome may lead to adverse pregnancy outcomes. Normal pregnancy is associated with changes in the vaginal bacterial community composition, which tend to be more enriched with one or two Lactobacillus species promoting a healthy vagina and favorable birth outcomes. The aim of the current study was to determine compositional changes in the healthy vaginal microbiome composition during the three trimesters of pregnancy in Ismailia, Egypt using Illumina MiSeq sequencing of the V3-V4 region of the 16S rRNA. The phylum Firmicutes and the genus Lactobacillus dominated across the three trimesters of pregnancy. L. iners was the most abundant species. However, L. coleohominis and L. reuteri represented the least dominant vaginal lactobacilli. Core microbiome analyses showed the Lactobacillus genus and L. iners species to have the highest prevalence in all the samples of our study groups. The phylum Firmicutes was found to be negatively correlated with almost all other vaginal phyla during pregnancy. Likewise, a negative correlation between Lactobacillus and almost all other genera was detected, including significant negative correlations with Dialister and Prevotella. Furthermore, negative correlations of L. iners were detected with almost all other species, including a significant negative correlation with L. helveticus, G. vaginalis, S. anginosus, and S. agalactiae.

Biofilm elimination from infected root canals using four different single files.

INTRODUCTION: Enterococcus faecalis (E. faecalis) is the most commonly isolated bacterium from infected root canals. It is found in the form of a biofilm, which makes it more resistant to antimicrobials, and requires optimal chemomechanical strategies to maximize root canal disinfection. AIM: To evaluate the efficacy of 4 different endodontic file systems against E. faecalis biofilm growth in root canals using colony-forming units per milliliter (CFU/mL) and scanning electron microscope (SEM). METHODS: Eighty-five extracted human mandibular premolars with straight root canals and apical diameters not larger than the #15 K-file were randomly selected. After performing a pilot study (n = 15) to determine the ideal incubation period for E. faecalis biofilm development, sixty-five root canals were infected with E. faecalis, incubated for 3 weeks, and then mechanically prepared using one of four single files (XP-endo Shaper, Hyflex EDM, One Curve, and Fanta. AFTM F One) (n = 15). Five infected root canals were excluded for the positive control. Five non-contaminated root canals were included for the negative control. Samples were collected using sterile paper points pre- and post-instrumentation to determine the bacterial load (CFU/mL). Root canals from each group were topographically evaluated at the coronal, middle, and apical segments using scanning electron microscope (SEM). Bacterial reduction data were estimated and statistically analyzed by Kruskal-Wallis and Mann-Whitney U tests (post hoc test) (P ≤ .05). RESULTS: XP-endo Shaper, Hyflex DEM, and One Curve significantly could eradicate E. faecalis biofilms in infected root canals with no significant difference among them compared to Fanta. AF™ F One. CONCLUSION: None of the systems were capable of completely eliminating biofilms. XP-endo Shaper, Hyflex EDM, and One Curve mechanically eliminated E. faecalis biofilms compared to Fanta. AF™ F One from infected root canals.

Alterations of the vaginal microbiome in healthy pregnant women positive for group B Streptococcus colonization during the third trimester.

BACKGROUND: Streptococcus agalactiae or group B Streptococcus (GBS) asymptomatically colonizes the genitourinary tracts of up to 30% of pregnant women. Globally, GBS is an important cause of neonatal morbidity and mortality. GBS has recently been linked to adverse pregnancy outcomes. The potential interactions between GBS and the vaginal microbiome composition remain poorly understood. In addition, little is known about the vaginal microbiota of pregnant Egyptian women. RESULTS: Using V3-V4 16S rRNA next-generation sequencing, we examined the vaginal microbiome in GBS culture-positive pregnant women (22) and GBS culture-negative pregnant women (22) during the third trimester in Ismailia, Egypt. According to the alpha-diversity indices, the vaginal microbiome of pregnant GBS culture-positive women was significantly more diverse and less homogenous. The composition of the vaginal microbiome differed significantly based on beta-diversity between GBS culture-positive and culture-negative women. The phylum Firmicutes and the family Lactobacillaceae were significantly more abundant in GBS-negative colonizers. In contrast, the phyla Actinobacteria, Tenericutes, and Proteobacteria and the families Bifidobacteriaceae, Mycoplasmataceae, Streptococcaceae, Corynebacteriaceae, Staphylococcaceae, and Peptostreptococcaceae were significantly more abundant in GBS culture-positive colonizers. On the genus and species levels, Lactobacillus was the only genus detected with significantly higher relative abundance in GBS culture-negative status (88%), and L. iners was the significantly most abundant species. Conversely, GBS-positive carriers exhibited a significant decrease in Lactobacillus abundance (56%). In GBS-positive colonizers, the relative abundance of the genera Ureaplasma, Gardnerella, Streptococcus, Corynebacterium, Staphylococcus, and Peptostreptococcus and the species Peptostreptococcus anaerobius was significantly higher. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways related to the metabolism of cofactors and vitamins, phosphatidylinositol signaling system, peroxisome, host immune system pathways, and host endocrine system were exclusively enriched among GBS culture-positive microbial communities. However, lipid metabolism KEGG pathways, nucleotide metabolism, xenobiotics biodegradation and metabolism, genetic information processing pathways associated with translation, replication, and repair, and human diseases (Staphylococcus aureus infection) were exclusively enriched in GBS culture-negative communities. CONCLUSIONS: Understanding how perturbations of the vaginal microbiome contribute to pregnancy complications may result in the development of alternative, targeted prevention strategies to prevent maternal GBS colonization. We hypothesized associations between inferred microbial function and GBS status that would need to be confirmed in larger cohorts.

Characterization, antibacterial, antioxidant, antidiabetic, and anti-inflammatory activities of green synthesized silver nanoparticles using Phragmanthera austroarabica A. G. Mill and J. A. Nyberg extract.

Introduction: Diabetes mellitus is a chronic metabolic disorder that exhibited great expansion all over the world. It is becoming an epidemic disease adding a major burden to the health care system, particularly in developing countries. Methods: The plant under investigation in the current study Phragmanthera austroarabica A. G. Mill and J. A. Nyberg is traditionally used in Saudi Arabia for the treatment of diabetes mellitus. The methanolic extract (200 mg/kg) of the plant and pure gallic acid (40 mg/kg), a major metabolite of the plant, as well as their silver nanoparticle formulae (AgNPs) were evaluated for their antidiabetic activity. Results and Discussion: The results showed a decrease in body fat, obesity, an improvement in lipid profiles, normalization of hyperglycemia, insulin resistance, and hyperinsulinemia, and an improvement in liver tissue structure and function. However, the results obtained from AgNPs for both extract and the pure gallic acid were better in most measured parameters. Additionally, the activity of both the crude extract of the plant and its AgNPs were evaluated against a number of gram-positive, gram-negative bacteria and fungi. Although the activity of the crude extract ranged from moderate to weak or even non-active, the AgNPs of the plant extract clearly enhanced the antimicrobial activity. AgNPs of the extract demonstrated remarkable activity, especially against the Gram-negative pathogens Proteus vulgaris (MIC 2.5 µg/ml) and Pseudomonas aeruginosa (MIC 5 µg/ml). Furthermore, a promising antimicrobial activity was shown against the Gram-positive pathogen Streptococcus mutants (MIC 1.25 µg/ml).

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.

Group B Streptococcal Colonization in African Countries: Prevalence, Capsular Serotypes, and Molecular Sequence Types.

Streptococcus agalactiae or group B streptococcus (GBS) is a commensal of the gastrointestinal and genitourinary tracts of healthy women and an important cause of neonatal invasive infections worldwide. Transmission of bacteria to the newborn occurs at birth and can be prevented by intrapartum antibiotic prophylaxis. However, this not available in resource limited settings in Africa, which carries a particular high burden of disease. Serotype based vaccines are in development and present a suitable alternative to prevent neonatal infections. To be able to assess vaccine efficacy, knowledge and surveillance of GBS epidemiological data are required. This review summarizes investigations about the serotype distribution and the multi-locus sequence types (MLST) found in different African countries. While most serotypes and MLST data are comparable to findings from other continents, some specific differences exist. Serotype V is predominant among colonizing maternal strains in many different African countries. Serotypes that are rarely detected in western industrialized nations, such as serotypes VI, VII and IX, are prevalent in studies from Ghana and Egypt. Moreover, some specific MLST sequence types that seem to be more or less unique to Africa have been detected. However, overall, the data confirm that a hexavalent vaccine can provide broad coverage for the African continent and that a protein vaccine could represent a promising alternative.

Group B Streptococcal Colonization, Molecular Characteristics, and Epidemiology.

Streptococcus agalactiae or group B streptococcus (GBS) is a leading cause of serious neonatal infections. GBS is an opportunistic commensal constituting a part of the intestinal and vaginal physiologic flora and maternal colonization is the principal route of GBS transmission. GBS is a pathobiont that converts from the asymptomatic mucosal carriage state to a major bacterial pathogen causing severe invasive infections. At present, as many as 10 serotypes (Ia, Ib, and II-IX) are recognized. The aim of the current review is to shed new light on the latest epidemiological data and clonal distribution of GBS in addition to discussing the most important colonization determinants at a molecular level. The distribution and predominance of certain serotypes is susceptible to variations and can change over time. With the availability of multilocus sequence typing scheme (MLST) data, it became clear that GBS strains of certain clonal complexes possess a higher potential to cause invasive disease, while other harbor mainly colonizing strains. Colonization and persistence in different host niches is dependent on the adherence capacity of GBS to host cells and tissues. Bacterial biofilms represent well-known virulence factors with a vital role in persistence and chronic infections. In addition, GBS colonization, persistence, translocation, and invasion of host barriers are largely dependent on their adherence abilities to host cells and extracellular matrix proteins (ECM). Major adhesins mediating GBS interaction with host cells include the fibrinogen-binding proteins (Fbs), the laminin-binding protein (Lmb), the group B streptococcal C5a peptidase (ScpB), the streptococcal fibronectin binding protein A (SfbA), the GBS immunogenic bacterial adhesin (BibA), and the hypervirulent adhesin (HvgA). These adhesins facilitate persistent and intimate contacts between the bacterial cell and the host, while global virulence regulators play a major role in the transition to invasive infections. This review combines for first time epidemiological data with data on adherence and colonization for GBS. Investigating the epidemiology along with understanding the determinants of mucosal colonization and the development of invasive disease at a molecular level is therefore important for the development of strategies to prevent invasive GBS disease worldwide.

Acid Stress Response Mechanisms of Group B Streptococci.

Group B streptococcus (GBS) is a leading cause of neonatal mortality and morbidity in the United States and Europe. It is part of the vaginal microbiota in up to 30% of pregnant women and can be passed on to the newborn through perinatal transmission. GBS has the ability to survive in multiple different host niches. The pathophysiology of this bacterium reveals an outstanding ability to withstand varying pH fluctuations of the surrounding environments inside the human host. GBS host pathogen interations include colonization of the acidic vaginal mucosa, invasion of the neutral human blood or amniotic fluid, breaching of the blood brain barrier as well as survival within the acidic phagolysosomal compartment of macrophages. However, investigations on GBS responses to acid stress are limited. Technologies, such as whole genome sequencing, genome-wide transcription and proteome mapping facilitate large scale identification of genes and proteins. Mechanisms enabling GBS to cope with acid stress have mainly been studied through these techniques and are summarized in the current review.

Making Fluorescent Streptococci and Enterococci for Live Imaging.

Since the discovery of the green fluorescent protein (GFP) from the jellyfish Aequorea victoria, outstanding fluorescent labeling tools with numerous applications in vastly different areas of life sciences have been developed. To optimize GFP for diverse life science applications, a large variety of GFP derivatives with different environmental characteristics have been generated by mutagenesis. The enhanced green fluorescent protein (EGFP) is a well-known GFP derivative with highly increased fluorescence intensity compared to the GFP wild-type molecule. Further optimization strategies include numerous GFP derivatives with blue- and yellow-shifted fluorescence and increased pH-stability. The methods reported herein describe in detail the construction of customized fluorescent GFP reporter plasmids where the fluorescence gene is expressed under the control of a certain bacterial promoter of interest. Special attention is given to the GFP derivatives EGFP and Sirius. We explain how to generate EGFP/Sirius expressing streptococci and how to employ recombinantly labeled streptococci in different downstream fluorescent applications.

A streptococcal NRAMP homologue is crucial for the survival of Streptococcus agalactiae under low pH conditions.

Streptococcus agalactiae or Group B Streptococcus (GBS) is a commensal bacterium of the human gastrointestinal and urogenital tracts as well as a leading cause of neonatal sepsis, pneumonia and meningitis. Maternal vaginal carriage is the main source for GBS transmission and thus the most important risk factor for neonatal disease. Several studies in eukaryotes identified a group of proteins natural resistance-associated macrophage protein (NRAMP) that function as divalent cation transporters for Fe(2+) and Mn(2+) and confer on macrophages the ability to control replication of bacterial pathogens. Genome sequencing predicted potential NRAMP homologues in several prokaryotes. Here we describe for the first time, a pH-regulated NRAMP Mn(2+) /Fe(2+) transporter in GBS, designated MntH, which confers resistance to reactive oxygen species (ROS) and is crucial for bacterial growth and survival under low pH conditions. Our investigation implicates MntH as an important colonization determinant for GBS in the maternal vagina as it helps bacteria to adapt to the harsh acidic environment, facilitates bacterial adherence, contributes to the coexistence with the vaginal microbiota and plays a role in GBS intracellular survival inside macrophages.

Chromosomally and Extrachromosomally Mediated High-Level Gentamicin Resistance in Streptococcus agalactiae.

Streptococcus agalactiae (group B Streptococcus [GBS]) is a leading cause of sepsis in neonates. The rate of invasive GBS disease in nonpregnant adults also continues to climb. Aminoglycosides alone have little or no effect on GBS, but synergistic killing with penicillin has been shown in vitro. High-level gentamicin resistance (HLGR) in GBS isolates, however, leads to the loss of a synergistic effect. We therefore performed a multicenter study to determine the frequency of HLGR GBS isolates and to elucidate the molecular mechanisms leading to gentamicin resistance. From eight centers in four countries, 1,128 invasive and colonizing GBS isolates were pooled and investigated for the presence of HLGR. We identified two strains that displayed HLGR (BSU1203 and BSU452), both of which carried the aacA-aphD gene, typically conferring HLGR. However, only one strain (BSU1203) also carried the previously described chromosomal gentamicin resistance transposon designated Tn3706. For the other strain (BSU452), plasmid purification and subsequent DNA sequencing resulted in the detection of plasmid pIP501 carrying a remnant of a Tn3 family transposon. Its ability to confer HLGR was proven by transfer into an Enterococcus faecalis isolate. Conversely, loss of HLGR was documented after curing both GBS BSU452 and the transformed E. faecalis strain from the plasmid. This is the first report showing plasmid-mediated HLGR in GBS. Thus, in our clinical GBS isolates, HLGR is mediated both chromosomally and extrachromosomally.

Macrolide- and tetracycline-resistance determinants of colonizing group B streptococcus in women in Egypt.

Group B streptococcus (GBS) is a commensal bacterium of the human gastrointestinal and genital tracts. It is a leading cause of neonatal sepsis and meningitis, and has also been recognized as an important pathogen in pregnant women and the elderly. We investigated mechanisms of macrolide and tetracycline resistance in GBS colonizing women in Egypt. A total of 100 isolates were screened using standard antibiotic susceptibility tests. A multiplex PCR assay was used to detect macrolide- and tetracycline-resistance determinants. All isolates were uniformly susceptible to penicillin G, ampicillin, cefotaxime, vancomycin and levofloxacin. The resistance rates to erythromycin, clindamycin, azithromycin, tetracycline and chloramphenicol were 17, 14, 16, 98 and 1 %, respectively. Among the erythromycin-resistant isolates, 82.4 % had constitutive macrolide-lincosamide-streptogramin B (cMLSB) resistance, 5.9 % had inducible MLSB (iMLSB) resistance and 11.8 % had M phenotype resistance. Among the cMLSB phenotypes, 64.3 % of isolates harboured the ermB gene and 35.7 % of isolates harboured none of the investigated macrolide-resistance genes. The single strain expressing the iMLSB phenotype possessed the ermA gene. Of the two strains with the M phenotype, only one possessed the mefA/E gene. Conversely, seven macrolide-sensitive strains (MIC <0.03 µg ml(-1)) were ermB positive and one macrolide-sensitive strain (MIC <0.03 µg ml(-1)) harboured mefA/E. Tetracycline resistance was predominantly due to tetM, which was detected alone (83.7 %) or in association with tetL (12.2 %), tetK (1 %) or tetO (1 %). One strain carried tetM associated with both tetL and tetK, and another strain carried tetO alone. The tetO strains were positive for the mefA/E gene, and the tetL and tetK carrier strains harboured the ermB gene. Susceptible strains harbouring but not expressing an antibiotic-resistance gene should be regarded as potentially resistant. These results emphasize the need to monitor the epidemiology of GBS antibiotic resistance in Egypt.

Metal binding is critical for the folding and function of laminin binding protein, Lmb of Streptococcus agalactiae.

Lmb is a 34 kDa laminin binding surface adhesin of Streptococcus agalactiae. The structure of Lmb reported by us recently has shown that it consists of a metal binding crevice, in which a zinc ion is coordinated to three highly conserved histidines. To elucidate the structural and functional significance of the metal ion in Lmb, these histidines have been mutated to alanine and single, double and triple mutants were generated. These mutations resulted in insolubility of the protein and revealed altered secondary and tertiary structures, as evidenced by circular dichroism and fluorescence spectroscopy studies. The mutations also significantly decreased the binding affinity of Lmb to laminin, implicating the role played by the metal binding residues in maintaining the correct conformation of the protein for its binding to laminin. A highly disordered loop, proposed to be crucial for metal acquisition in homologous structures, was deleted in Lmb by mutation (ΔLmb) and its crystal structure was solved at 2.6 Å. The ΔLmb structure was identical to the native Lmb structure with a bound zinc ion and exhibited laminin binding activity similar to wild type protein, suggesting that the loop might not have an important role in metal acquisition or adhesion in Lmb. Targeted mutations of histidine residues confirmed the importance of the zinc binding crevice for the structure and function of the Lmb adhesin.

Comparison of scpB gene and cfb gene polymerase chain reaction assays with culture on Islam medium to detect Group B Streptococcus in pregnancy.

PURPOSE: The purpose of the current study was to evaluate two low-costing PCR assays for rapid detection of Group B Streptococcus (GBS) in comparison to a pigment-based culture method. MATERIALS AND METHODS: One-hundred and fifty vaginal swabs were collected from pregnant women at 35-40 weeks of gestation. Vaginal swabs were inoculated in selective enrichment broth medium, and examined using Islam medium, cfb PCR and scpB PCR assays. The demographic data were analysed to identify independent predictors of GBS colonization (age and gravidity), with GBS status as the dependent variable. RESULTS: There was a significant association of age and gravidity with GBS colonization. GBS was detected in 25.3% of isolates by Islam medium, in 30.6% by using the cfb PCR assay and in 30% by using the scpB PCR assay. CONCLUSION: Older pregnant women (≥30 years) and multigravida (>3 pregnancies) are at higher risk of GBS colonization. Both scpB-gene and cfb-gene-based PCR methods are highly sensitive techniques (100% sensitivity) compared to culture method. However, the specificities of the scpB and cfb PCR assays were 93.75 and 92.85%, respectively.

Vaginal carriage and antibiotic susceptibility profile of group B Streptococcus during late pregnancy in Ismailia, Egypt.

Group B Streptococcus (GBS) infection has long been recognized as a frequent cause of morbidity and mortality in newborn infants. The purpose of this study was to determine the colonization rate with GBS and the antibiotic susceptibility profile in pregnant women attending Gynecological clinics in Egypt. One-hundred and fifty vaginal swabs were collected from pregnant women at 35-40 weeks of gestation. In comparison to culture, direct latex agglutination testing revealed 100% sensitivity and 93.75% specificity. Thirty-eight specimens (25.3%) were found to be positive for GBS. Each isolate was tested for susceptibility to penicillin G, ampicillin, cefotaxime, erythromycin, clindamycin and vancomycin. Erythromycin-resistant isolates were further classified by double-disk method. All isolates were susceptible to penicillin G, ampicillin and vancomycin. Resistance to cefotaxime was detected in three isolates (7.89%). Five isolates (13.15%) were resistant to erythromycin and nine isolates (23.68%) were resistant to clindamycin. Four (80%) isolates had constitutive macrolide-lincosamide-Streptogramin(B) resistance (cMLSB(B)) resistance and one (20%) isolate had inducible resistance (iMLS(B)) resistance. GBS colonization was found to be high in our region. Latex agglutination testing and Islam medium are reliable methods to detect GBS in late pregnancy; however, latex agglutination test is rapid and simpler. Penicillin G remains the first choice antibiotic for treatment of GBS infections.