Emergence Of Enterococci Research Articles

A bacteriocin expression platform for targeting pathogenic bacterial species

Bacteriocins are antimicrobial peptides that are naturally produced by many bacteria. They hold great potential in the fight against antibiotic resistant bacteria, including ESKAPE pathogens. Engineered live biotherapeutic products (eLBPs) that secrete bacteriocins can be created to deliver targeted bacteriocin production. Here we develop a modular bacteriocin secretion platform that can be used to express and secrete multiple bacteriocins from non-pathogenic Escherichia coli host strains. As a proof of concept we create Enterocin A (EntA) and Enterocin B (EntB) secreting strains that show strong antimicrobial activity against Enterococcus faecalis and Enterococcus faecium in vitro, and characterise this activity in both solid culture and liquid co-culture. We then develop a Lotka-Volterra model that can be used to capture the interactions of these competitor strains. We show that simultaneous exposure to EntA and EntB can delay Enterococcus growth. Our system has the potential to be used as an eLBP to secrete additional bacteriocins for the targeted killing of pathogenic bacteria.

Enterococcus spp. in fish: Analysis of the presence and resistance in samples from Tri-City, Poland.

The growing concern over antibiotic resistance in foodborne pathogens necessitates comprehensive assessments of its prevalence and associated risks in various food products. The present study aimed to assess the occurrence of Enterococcus spp. in samples of fish purchased at various points of sale in the Tricity region. The selection of products (n = 74) was based on their availability and included both fish caught in the Baltic region and products imported from, Vietnam, China, Norway, and European Union (EU) countries. For bacterial isolation, samples were inoculated into selective broth, and the growth of enterococci was assessed based on turbidity. Positive cultures were confirmed by a change in color in bromocresol purple broth and were isolated on Slanetz-Bartley agar. Bacteria were present in all tested samples regardless of the degree of raw material processing as follows: frozen (F)- 55%, fresh/raw (FS)- 70.6%, thawed (DF)- 30%, smoked (S)- 50%, and the packaging methods, modified atmosphere packaging (MAP)- 34.4%, unit packaging (UP)- 75%, and sold in bulk (SB)- 76.9%, with an overall frequency of occurrence of 58.1%. The number of bacteria ranged from not detected to 4.28-log cfu/g, with the lowest mean values for thawed fish and those packed in MAP. Tests conducted on 24 strains isolated from samples showed their varied sensitivity to tetracyclines. Single cases of multidrug resistance of the tested strains were also observed. The conducted statistical analysis did not show statistically significant differences in the count of enterococci based on the origin, degree of processing, or packaging (p < 0.05). Moreover, differences in strain sensitivity to ampicillin were observed. Detected cases of resistance, especially to tetracycline, require careful monitoring and action to limit the health risks associated with resistant bacterial strains in food products.

Recurrent Infective Endocarditis and Its Complication in an Individual with Two Different Organisms – A Rare Presentation

ABSTRACT Fungal endocarditis is rare and does not usually occur in structurally normal hearts. The most common causative agent is Candida albicans. We report a 30-year-old male presenting with low-grade fever and shortness of breath. Two-dimensional echocardiography revealed ostium secundum atrial septal defect with vegetations over tricuspid and mitral valves. Blood culture showed the growth of Enterococcus sp. which was successfully managed by antibiotic therapy. 1.5 months after, the patient again presented with fever and features of heart failure. Echocardiography showed large mobile vegetations over tricuspid and mitral valves. This time blood culture showed growth of Candida tropicalis. The patient developed septic embolization in the right leg which was promptly managed with surgical intervention. The patient was further managed with medical and surgical intervention and was discharged in stable condition.

Nutritional Strategies To Improve VRE Control

The rise of Vancomycin-resistant enterococci (VRE) strains among cellular therapy recipients raises concerns due to increased morbidity, mortality, and hospitalization costs, particularly impacting transplanted patients with diminished survival expectations. Recent research linking lactose to Enterococcus growth and graft-versus-host disease (GVHD) emphasizes the need for data on reducing lactose in the diets of VRE-carrying patients, especially in cellular therapy contexts like CAR-T or allogeneic hematopoietic stem cell transplantation. Responding to elevated VRE positivity rates in rectal swabs among patients in our BMT Unit, a unique nutritional strategy was implemented, introducing lactose-free milk and strictly enforcing lactose-free diets. This approach resulted in a significant reduction in VRE carriers, with a 16% positivity rate in the Lactose Group versus 3.6% in the Lactose-Free Group, as of June 2023. These results indicate the potential efficacy of this innovative nutritional strategy in high-risk departments, such as BMT Units and Intensive Care Units, with implications for reducing isolation strategies and inappropriate antibiotic use in cases of VRE colonization.

THE PREVALENCE, ISOLATION, AND ANTIMICROBIAL SUSCEPTIBILITY TESTING OF ENTEROCOCCUS SPECIES FROM VARIOUS CLINICAL SAMPLES IN A TERTIARY CARE HOSPITAL

Background: Enterococcus is routinely considered a low-grade pathogen. The synergistic action of Enterococci with other bacteria increases the risk of infection. Enterococci are currently the next most common cause of healthcare-associated infections after E. coli. Greater understanding is needed regarding Enterococcus stress survival, virulence, and resistance patterns to assess the complexity of disease-causing Enterococcus. Purpose: Analyze the prevalence of Enterococcus and assess the antibiotic sensitivity pattern of Enterococcus. Method: A descriptive cross-sectional study was designed and carried out in the Department of Microbiology at Bangladesh University of Health Sciences, Dhaka, over a period of 3 months. Bacterial culture and sensitivity were the methods employed for microbiological examination. Result: A total of 558 bacterial strains were isolated, among which the growth of Enterococcus spp. was 27 (4.83%). The prevalence of Enterococcus spp. among different samples was 4.83%. The number of highly sensitive strains ranged from 66.66% to 77.77% for antibiotics, namely gentamycin, ampicillin, amoxicillin, and meropenem. Moderately high sensitivity to levofloxacin (29.62%) and low sensitivity to doxycycline (14.81%) were also analyzed. Conclusion: The study recommends that antibiotics should be used after proper laboratory procedures are undertake, and it should be selected based on antimicrobial susceptibility tests.

Clinical Differences in Dogs with Enterococcal Bacteriuria Compared with Other Bacteriuria: A Retrospective, Case-Control Study.

A retrospective case-control study was performed to determine the clinical differences between dogs with enterococcal bacteriuria (n = 96 cases) and control dogs with any other bacteriuria (n = 288). More dogs with nonenterococcal bacteriuria demonstrated lower urinary tract clinical signs such as hematuria, pollakiuria, and stranguria (40% versus 27%, P = .02). Recessed vulva (odds ratio [OR] 2.5, 95% confidence interval [CI] 1.4-4.2, P < .001), hyperadrenocorticism (OR 0.149, 95% CI 0.004-0.066, P = .03), chronic kidney disease (OR 2.29, 95% CI 1.14-4.51, P = .01), and myelopathy (OR 5.77, 95% CI 3.07-10.82, P < .001) were more common in dogs with enterococcal bacteriuria. Enterococcus spp. cases were more likely to have polymicrobial growth than controls (OR 28.52; 95% CI 12.63-69.62, P ≤ .001). Pugs (OR 7.4, 95% CI 2.6-19.9, P < .001), bearded collies (OR 24.3, 95% CI 2.9-205.5, P = .003), and Saint Bernards (OR 17.3, CI 1.9-154.4, P = .01) had increased odds of enterococcal growth compared with mixed-breed dogs. In the control (but not the case) population, there was an association between resolution of clinical signs and administration of antimicrobials (P = .01). The signalment, clinical signs, comorbidities, and response to therapy in dogs with enterococcal bacteriuria are different from dogs with other bacteriuria.

Modulatory effects of fermented Polygonatum cyrtonema Hua on immune homeostasis and gut integrity in a dextran-sulfate-sodium-induced colitis model.

The gut health-promoting properties of saponin-rich Polygonatum cyrtonema Hua (FP) fermented with Lactobacillus plantarum P9 were explored in a dextran sulfate sodium (DSS)-induced colitis mouse model. FP supplementation effectively inhibited DSS-induced physiological alteration and impaired immune responses by reducing the disease activity index (DAI) score and restoring the T helper (Th) 1/Th2 and regulatory T (Treg)/Th17 ratios. In addition, FP supplementation protected the gut barrier function against DSS-induced damage via upregulation of zonula occludens (ZO)-1 and occludin and downregulation of pro-inflammatory cytokines, including interleukin (IL)-1β, tumor necrosis factor-α (TNF-α), IL-18, and the granulocyte-macrophage colony-stimulating factor (GM-CSF). This study further elucidated the potential mechanisms underlying the FP-mediated suppression of the plasticity of type 3 innate lymphoid cells (ILC3) and subsequent macrophage polarization. Therefore, the FP supplementation effectively restored mucosal immune homeostasis and enhanced gut integrity. In addition, it suppressed the growth of Escherichia-Shigella and Enterococcus and promoted the enrichment of probiotics and short-chain fatty acid-producing microbes, such as Romboutsia, Faecalibaculum, and Blautia. In conclusion, P. cyrtonema Hua fermented with L. plantarum P9 might be a promising dietary intervention to improve gut health by sustaining overall gut homeostasis and related gut integrity.

In vivo absorption and excretion in rats and in vitro digestion and fermentation by the human intestinal microbiota of 2-O-β-D-glucopyranosyl-L-ascorbic acid from the fruits of Lycium barbarum L.

2-O-β-D-Glucopyranosyl-L-ascorbic acid (AA-2βG) from Lycium barbarum fruits has diverse bioactivities, yet its absorption and digestion are poorly understood. Therefore, the in vivo absorption of AA-2βG in rats was investigated in the present study. After oral administration to SD rats, AA-2βG was absorbed intact, reaching a peak plasma concentration of 472.32 ± 296.64 nM at 90 min, with fecal excretion peaking at 4-8 h and decreasing rapidly by 12-24 h, indicating a prolonged intestinal presence. Furthermore, the digestibility under simulated gastrointestinal conditions and the impact on the gut flora through in vitro fermentation of AA-2βG were investigated. The results reveal that AA-2βG resisted in in vitro simulated digestion, indicating potential interactions with the gut microbiota. The results of in vitro fermentation showed that AA-2βG regulated the composition of the gut microbiota by promoting Oscillospiraceae, Faecalibacterium, Limosilactobacillus, and Fusicatenibacter, while inhibiting Enterococcus, Phocaeicola, Bacteroides, and Streptococcus. Furthermore, at the species level, AA-2βG promoted the growth of Limosilactobacillus mucosae and Faecalibacterium prausnitzii, and inhibited the growth of Enterococcus. F. prausnitzii is a major producer of n-butyric acid, and the results of short-chain fatty acids also demonstrated a significant promotion of n-butyric acid. Therefore, the study on the absorption, excretion, and regulatory effects of AA-2βG on the gut microbiota supported its potential development as a functional food additive to enhance intestinal health and prevent diseases.

Casein hydrolysate's effects on the fermentation properties, texture, and chemical characteristics and the bacterial microbiota of fermented glutinous rice dough

To investigate how casein hydrolysate affected the physicochemical properties and microbiological diversity of the glutinous rice dough (natural fermentation and yeast fermentation), we analyzed its fermentation properties, carbohydrate, protein degradation, texture, and bacterial composition. According to the findings, casein hydrolysate increased the total LAB number, as well as organic acid content, in naturally fermented and yeast fermented glutinous rice dough by 3.59 and 8.19%, respectively, and reduced the fermentation time by at least 2 h. Meanwhile, casein hydrolysate enhanced the content of reducing sugars by 4.46 and 13.53% and increased protease activity by 29.9 and 27.7%. In addition, casein hydrolysate accelerated protein breakdown and regulated the hardness of the dough to improve the texture. Casein hydrolysate enriched the bacterial richness and diversity of dough. After adding casein hydrolysate, it promoted the growth of Pediococcus, Enterococcus, Lactobacillus, and Streptococcus. According to the Spearman correlation analysis, environmental factors (pH, lactic acid, acetic acid, reducing sugar content, and protease activity) exhibited the major driver for the abundance of bacterial species (Spearman correlation coefficient: −0.71 to 0.78). As a potential food additive, casein hydrolysate can improve the fermentation and quality of glutinous rice dough, increase consumer acceptance of cereal foods, and give consumers healthier options.

Prebiotic characteristics of added-value polysaccharides from jackfruit peel waste during in vitro digestion and fecal fermentation

Food waste can be used more efficiently to increase food sustainability. Polysaccharides from jackfruit peel (PJP) are derived from agricultural waste, and little is known about their in vitro digestion and fermentation characteristics. This study aimed to elucidate PJP structural properties, the dynamic changes during in vitro simulated salivary gastrointestinal digestion and fecal fermentation, and its effects on the human intestinal microbiota. Structural analysis showed a typical polysaccharide structure with high stability in an amorphous heteropolysaccharide. The monosaccharides of PJP are glucose, mannose, galactose, arabinose, and rhamnose. In vitro digestion models, showed that the PJP can reach the colon intact. PJP degradation by the intestinal microbiota being during fecal fermentation, releasing free oligosaccharides, producing short-chain fatty acids, particularly acetic acid, and modulating the composition of intestinal microbes. PJP promoted the growth of beneficial flora Weissella, Enterococcus, Bifidobacterium, Lactococcus and Prevotella during the fermentation process. These findings could improve the usage of jackfruit peel waste, and create possibilities for its use as a potential prebiotic.

Sexual Dimorphism in Lipid Metabolism and Gut Microbiota in Mice Fed a High-Fat Diet.

The gut microbiome plays an essential role in regulating lipid metabolism. However, little is known about how gut microbiome modulates sex differences in lipid metabolism. The present study aims to determine whether gut microbiota modulates sexual dimorphism of lipid metabolism in mice fed a high-fat diet (HFD). Conventional and germ-free male and female mice were fed an HFD for four weeks, and lipid absorption, plasma lipid profiles, and apolipoprotein levels were then evaluated. The gut microbiota was analyzed by 16S rRNA gene sequencing. After 4-week HFD consumption, the females exhibited less body weight gain and body fat composition and significantly lower triglyceride levels in very-low-density lipoprotein (VLDL) and cholesterol levels in high-density lipoprotein (HDL) compared to male mice. The fecal microbiota analysis revealed that the male mice were associated with reduced gut microbial diversity. The female mice had considerably different microbiota composition compared to males, e.g., enriched growth of beneficial microbes (e.g., Akkermansia) and depleted growth of Adlercreutzia and Enterococcus. Correlation analyses suggested that the different compositions of the gut microbiota were associated with sexual dimorphism in body weight, fat mass, and lipid metabolism in mice fed an HFD. Our findings demonstrated significant sex differences in lipid metabolism and the microbiota composition at baseline (during LFD), along with sex-dependent responses to HFD. A comprehensive understanding of sexual dimorphism in lipid metabolism modulated by microbiota will help to develop more sex-specific effective treatment options for dyslipidemia and metabolic disorders in females.

Rapid Proteomic Characterization of Bacteriocin-Producing Enterococcus faecium Strains from Foodstuffs.

Enterococcus belongs to a group of microorganisms known as lactic acid bacteria (LAB), which constitute a broad heterogeneous group of generally food-grade microorganisms historically used in food preservation. Enterococci live as commensals of the gastrointestinal tract of warm-blooded animals, although they also are present in food of animal origin (milk, cheese, fermented sausages), vegetables, and plant materials because of their ability to survive heat treatments and adverse environmental conditions. The biotechnological traits of enterococci can be applied in the food industry; however, the emergence of enterococci as a cause of nosocomial infections makes their food status uncertain. Recent advances in high-throughput sequencing allow the subtyping of bacterial pathogens, but it cannot reflect the temporal dynamics and functional activities of microbiomes or bacterial isolates. Moreover, genetic analysis is based on sequence homologies, inferring functions from databases. Here, we used an end-to-end proteomic workflow to rapidly characterize two bacteriocin-producing Enterococcus faecium (Efm) strains. The proteome analysis was performed with liquid chromatography coupled to a trapped ion mobility spectrometry-time-of-flight mass spectrometry instrument (TimsTOF) for high-throughput and high-resolution characterization of bacterial proteins. Thus, we identified almost half of the proteins predicted in the bacterial genomes (&gt;1100 unique proteins per isolate), including quantifying proteins conferring resistance to antibiotics, heavy metals, virulence factors, and bacteriocins. The obtained proteomes were annotated according to function, resulting in 22 complete KEGG metabolic pathway modules for both strains. The workflow used here successfully characterized these bacterial isolates and showed great promise for determining and optimizing the bioengineering and biotechnology properties of other LAB strains in the food industry.

Charactering the spoilage mechanism of “three sticks” of Jinhua ham

To investigate the spoilage characteristics of Jinhua ham, sensory scores, volatile compounds, biogenic amine, physicochemical parameters and microbial counts were evaluated between normal and spoiled hams. The results showed that off-odors of spoiled hams were dominated by rancid, sour, sulfide and ammonia odors derived from these compounds including butanoic acid, methanethiol and dimethyl disulfide. Total content of biogenic amine in spoiled hams was significantly higher (more than 10-fold) compared with normal hams, and putrescine, cadaverine and histamine were the key components of biogenic amine of spoiled hams. Lower salt content, and higher moisture, TVB-N and thiobarbituric acid reactive substances (TBARS) values were observed in spoiled hams compared with normal hams. The populations of Enterobacteriaceae and Enterococcus of spoiled hams were obviously higher than that of normal hams. High moisture and low salt content caused the abnormal growth of Enterobacteriaceae and Enterococcus in spoiled hams, which contributed to the spoilage of Jinhua ham.

Enterococcal infections in a tertiary care hospital, North India.

The emergence of Enterococcus as an important nosocomial pathogen is mainly attributed to its inherent resistance to commonly used antibiotics and now in recent times, it has acquired resistance to other available therapeutic options as well. Enterococcus isolates from clinical samples received in the department of microbiology over a period of 1 year were included in the study. Isolates were identified and species determined by standard methods. Antibiotic susceptibility test was done by Kirby Bauer disc diffusion test. Epsilometer test was done to determine the minimum inhibitory concentration for vancomycin. A total of 145 Enterococcus isolates were obtained; 73 (50.3%) isolates were identified as Enterococcus faecalis, 69 (47.5%) Enterococcus faecium, 2 (1.3%) Enterococcus durans and 1 (0.68%) as Enterococcus gallinarum. Most of the isolates were from urine samples (125, 86.2%); followed by pus (16, 11.03%). Vancomycin resistance was seen in 14 (9.6%) isolates while linezolid resistance was seen in 8 (5.5%) isolates. E. faecalis is the most common clinical species isolated from clinical samples and the emergence of linezolid-resistant enterococci from the hospital is a matter of concern as till now it is considered to be the last resort for treatment in patients infected with vancomycin-resistant enterococci.

Staphylococcus aureus and Enterococcus faecium isolated from pigeon droppings (Columba livia) in the external environment close to hospitals.

ABSTRACTBackground: Domestic pigeons carry pathogens in their droppings, posing a potential public health problem. Methods: The phenotypic and genotypic antimicrobial resistances of Staphylococcus aureus and Enterococcus faecium in the feces of urban pigeons near hospitals with intensive care units were measured. Results: Twenty-nine samples showed Enterococcus growth, whereas one was positive for S. aureus. The S. aureus isolate was sensitive to the antibiotics tested via antibiogram, however resistance genes were identified. E. faecium isolates showed phenotypic resistance to gentamicin, erythromycin, and ciprofloxacin. Conclusions: Antimicrobial profiles harmful to health were demonstrated in bacterial pathogens isolated from the external environment of hospitals.

In-vitro anti-bacterial effectiveness test of 2% chlorhexidine digluconate and ethanol extract of green meniran leaves (Phyllanthus niruri Linn) on the growth of Enterococcus faecalis bacterial colony

Background: Necrotic teeth with periapical lesions often experience root canal treatment failure. Enterococcus faecalis bacteria cause 85-90% of root canal infections. 2% Chlorhexidine digluconate (CHX) can eliminate Enterococcus faecalis bacteria but cannot dissolve necrotic tissue, while green meniran phytochemical compounds (Phyllantus niruri Linn) have anti-bacterial properties. This study aims to determine the effectiveness, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) between green meniran leaf extract with 2% chlorhexidine digluconate and meniran extract only against the growth of Enterococcus faecalis.Method: This is an in vitro experimental study with a broth microdilution method consisting of two treatment groups. The negative control contained BHIB media and 0.05 ml of bacteria; the positive control had 0.05 ml of bacteria with 2% chlorhexidine digluconate, the group one consisted of BHIB media, bacteria and various concentrations of meniran extract. In contrast, group two consisted of BHIB media, bacteria, various concentrations of green meniran with 2% chlorhexidine digluconate. Data were analyzed using the One Way Anova test with LSD test.Results: Compared with negative control, in group one, we found the MIC of meniran extract was 3.125% with 94% anti-bacterial power, and the MBC was 6.25% with no bacterial growth. In group 2, we found the MIC of meniran extract and the 2% chlorhexidine digluconate was 0.78% with 9.3% anti-bacterial power, while the MBC was 1.56%.Conclusion: The increasing concentration of meniran extract also increases the anti-bacterial effect. A combination of meniran extract and 2% chlorhexidine digluconate give better anti-bacterial effects than meniran extract only.

Assessment of the Use of Gentian Violet and Malachite Green as Selective Agents in the Isolation of Brucella

The aim of the work is to evaluate ability of gentian violet and malachite green to inhibit 2 Brucella test strains and 8 strains of unwanted organisms and the influence of autoclaving on their activity. The study also aims to evaluate variability of inhibition in different batches of colorants and necessity in adjustment of their concentration.Materials and methods. The study included 3 imported lots of gentian violet and malachite green. Inhibitors were put into nutrient medium containing pancreatic hydrolysates of gelatin and fsh meal, yeast extract, sodium chloride, glucose, sodium pyrosulfate, and agar. The same medium without colorants was used as a control medium. Effect of the colorants was studied with the help of test strains of Brucella abortus 19 ВА, B. melitensis Rev I, Enterococcus faecium VKM B-602, Escherichia coli ATCC 25922, Proteus vulgaris HX 19 222, Pseudomonas aeruginosa 22/99, Serracia plymuthica 1, Shigella flexneri 1a 8516, Staphylococcus aureus ATCC 25923, Yersinia enterocolitica C-187.Results and discussion. We have determined biological parameters of nutrient media containing gentian violet (5,0; 2,5 1,25 mg/L) and malachite green (2.0; 1.0; 0.5 mg/L) when cultivating brucella. Gentian violet is able to inhibit Brucella greatly at concentration of 5 mg/L. S. aureus ATCC 25923 did not show any growth on the media containing malachite green or gential violet (5.0 and 2.5 mg/L). Malachite green inhibited the growth of enterococcus more actively than gentian violet. However, it inhibited swarming growth of Proteus less successfully than gentian violet. Other unwanted organisms were not sensitive to such concentrations of colorants at all. We have demonstrated the necessity to combine colorants with other selective agents, as well as advisability to put gentian violet into sterile media, while malachite green – into the media before its autoclaving. Adjustments to the concentration of gentian violet should be made when producing nutrient medium, as variations in inhibiting activity in different batches of this colorant were revealed.

The duo Clostridium and Lactobacillus linked to hydrogen production from a lignocellulosic substrate.

The study aimed to identify interspecies interactions within a native microbial community present in a hydrogen-producing bioreactor fed with two wheat straw cultivars. The relationships between the microbial community members were studied building a canonical correspondence analysis and corroborated through in vitro assays. The results showed that the bioreactor reached a stable hydrogen production of ca. 86 mL/kg·d in which the cultivar change did not affect the average performance. Lactobacillus and Clostridium dominated throughout the whole operation period where butyric acid was the main metabolite. A canonical correspondence analysis correlated positively Lactobacillus with hydrogen productivity and hydrogen-producing bacteria like Clostridium and Ruminococaceae. Agar diffusion testing of isolated strains confirmed that Lactobacillus inhibited the growth of Enterococcus, but not of Clostridium. We suggest that the positive interaction between Lactobacillus and Clostridium is generated by a division of labor for degrading the lignocellulosic substrate in which Lactobacillus produces lactic acid from the sugar fermentation while Clostridium quickly uses this lactic acid to produce hydrogen and butyric acid. The significance of this work lies in the fact that different methodological approaches confirm a positive association in the duo Lactobacillus-Clostridium in a bioreactor with stable hydrogen production from a complex substrate.

Особенности микробиоты желудка пациентов с Helicobacter pylori-ассоциированными заболеваниями

Scientists consider changes in the composition of the stomach microbiota in the presence of Helicobacter pylori as an additional factor inducing inflammation and dystrophy of the gastric mucosa. Purpose. The assessment of the gastric microbiota in patients with H. pylori-associated diseases. Material and methods. The study involved 20 patients with chronic stomach diseases: 10 patients were H. pylori-positive; 10 persons were H. pylori-negative (control group). Patients underwent sampling of the gastric lining followed by histological and microbiological examination of inoculation on nutrient media, determining the urease activity in the biopsy specimen and total antibodies to the H. pylori CagA antigen. Results. 90% of H. pylori-positive patients showed growth of Enterococcus spp. on a nutrient medium against 30% of individuals in the control group (p = 0.02). Growth of Enterococcus spp. in patients with helicobacteriosis reached 5.8 [5.2; 6.4] lg CFU/g, in H. pylori-negative persons 4.8 [4.3; 5.0] lg CFU/g (p = 0.04). In the control group, no fungal microflora was found, in 40% of H. pylori-positive individuals, the growth of Candida spp. reached 5.9 [5.6; 6.4] lg CFU/g. Growth of Staphylococcus spp. and Lactobacillus spp. did not have significant differences in the groups. In patients with more severe symptoms of dyspepsia, Enterococcus spp. were present in the stomach microbiota (r = 0.52, p &lt; 0.05). Conclusion. Microbiota of the stomach in patients with H. pylori-associated diseases is polymorphic; it includes Enterococcus spp., Staphylococcus spp., Lactobacillus spp., Candida spp. Enterococcus spp. are three times more likely to be present in the stomach microbiota in H. pylori-positive patients than in H. pylori-negative individuals (p &lt; 0.05). The presence of Enterococcus spp. in the microbiota of the stomach was significantly associated with more severe symptoms of dyspepsia.

Phenotypic Characterisation, Virulence Determination and Antimicrobial Resistance Pattern of Enterococcus Species Isolated from Clinical Specimen in a Tertiary Care Hospital in Kolkata

Introduction: Enterococci are usually normal human commensal of gastrointestinal tract predominantly. They are considered as an important nosocomial pathogen now a day due to its intrinsic as well as increasing acquired antibiotic resistance resulting in a great threat to modern Medicine. Aim: To determine prevalence of Enterococci isolated from clinical specimens with special reference to its virulence and antibiogram conventionally. Materials and Methods: A cross-sectional observational study was conducted over a period of two years (January 2019 to December 2020) with 326 Enterococci, isolated from various clinical specimens received by Department of Microbiology. Enterococci isolated from stool samples were excluded. They were identified and speciated conventionally as per standard laboratory protocol. Gelatinase, haemolysin and biofilm formation was determined for each isolate. Their antibiogram was also determined by disc diffusion methods over Blood agar followed by Minimum Inhibitory Concentration (MIC) testing (as per Clinical and Laboratory Standards Institute (CLSI) guideline). All statistical analysis was done by Chi-square test using Software Statistical Package for the Social Sciences (SPSS) version 22.0. Results: Among the total 4516 samples collected, growth of Enterococci was noted in 7.22% cases. Out of them, E. faecalis (84.05%) out numbered E. faecium. Urine was the most predominant (55.22%) sample. 73.93% isolates produced biofilm whereas 18.40% produced haemolysin and 19.94% produced gelatinase. Most of the isolates were susceptible to vancomycin (94.79%) and linezolid (98.77%). High level gentamicin resistance was seen in 54.6% cases. Ciprofloxacin was the most resistant antibiotic. Vancomycin Resistance Enterococcus (VRE) was detected in 5.21% cases only, out of which Van A type was detected phenotypically in most cases. Conclusion: The high rate of resistance to high-level gentamicin could fail treatment of gentamicin in combination with penicillin group of antibiotics. In clinical samples, the emergence of VRE strains makes treatment options more challenging.