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9 results on '"Tanya Strateva"'

1. Incidence of virulence determinants in clinical Enterococcus faecalis and Enterococcus faecium isolates collected in Bulgaria

Author

Tanya Strateva, Daniela Atanasova, Encho Savov, Guergana Petrova, and Ivan Mitov

Subjects
Infectious and parasitic diseases, RC109-216, Microbiology, QR1-502
Abstract

Objectives: To evaluate the prevalence of some virulence genes among 510 clinical Enterococcus spp. isolates and to assess the association of those genes with the species, infection site, and patient group (inpatients/outpatients). Methods: Adhesins genes (aggregation substances agg and asa1 of Enterococcus faecalis and Enterococcus faecium, respectively), enterococcal surface protein (esp), endocarditis-specific antigen A (efaA), collagen-binding proteins (ace/acm)); invasins (hyaluronidase (hyl) and gelatinase (gelE)); cytotoxines (activation of cytolysin (cylA) in E. faecalis); and modulators of the host immunity and inflammation (enhanced expression pheromone (eep) in E. faecalis) were detected by polymerase chain reaction. Results: The overall prevalence was: esp – 44.3%, agg/asa1 – 38.4%, ace/acm – 64.3%, efaA – 85.9%, eep – 69.4%, gelE – 64.3%, hyl – 25.1%, and cylA – 47.1%. E. faecalis isolates had significantly higher frequency of adhesin genes (esp and agg/asa1) and gelatinase in comparison to E. faecium. Multiple virulence genes in E. faecalis were significantly more prevalent than in E. faecium isolates. Domination of E. faecium with or without only one gene compared to the isolates of E. faecalis were found. Enterococcus spp. isolates obtained from outpatients compared to inpatients isolates had significantly higher frequency of agg/asa1, eep, gelE and cylA. Some adhesins genes (esp, agg/asa1 and efaA) had higher prevalence among the non-invasive Enterococcus spp. isolates compared to those causing invasive bacteremia, while ace/acm revealed higher dissemination in isolates causing invasive infections compared to non-invasive isolates. Conclusion: Most E. faecalis attaches to abiotic surfaces in hospital environment, which correlates with higher prevalence of gene encoding for virulence factors involved in biofilm formation, such as enterococcal surface protein, aggregation substance, and gelatinase. The intestinal tract is an important reservoir for opportunistic enterococcal pathogens and allows them to access infectious sites through different virulence factors, demonstrated in outpatient isolates in this study. Keywords: Enterococcus faecalis, Enterococcus faecium, Virulence genes, Prevalence

Published
2016
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8. Gardnerella vaginalis-associated bacterial vaginosis in Bulgarian women

Author

Raina Gergova, Ivan Mitov, and Tanya Strateva

Subjects
Microbiology (medical), Vaginal discharge, Adult, medicine.medical_specialty, Adolescent, lcsh:QR1-502, Reproductive age, medicine.disease_cause, Polymerase Chain Reaction, Sensitivity and Specificity, lcsh:Microbiology, lcsh:Infectious and parasitic diseases, Young Adult, Culture Techniques, medicine, Gardnerella vaginalis, Humans, lcsh:RC109-216, Young adult, Bulgaria, Medicine(all), Gynecology, Vaginal Smears, Laboratory methods, business.industry, Bulgarian women, Vaginosis, Bacterial, Bacterial vaginosis, medicine.disease, Infectious Diseases, Female, medicine.symptom, business
Abstract

Background: Bacterial vaginosis (BV) is the most common cause of vaginal discharge in women of reproductive age. The purpose of this study was to determine the frequency of BV in Bulgarian pregnant and nonpregnant women from several age ranges and to compare three different laboratory methods for Gardnerella vaginalis detection in patents suffering from BV. Methods: Between September 2011 and June 2012, 809 women of 16–40 years of age separated in two major groups: nonpregnant – 469 (355 with and 114 without symptoms) and pregnant – 340 (213 and 127 respectively) were enrolled for the study. The women underwent three different laboratory tests simultaneously: scoring of Gram staining of vaginal smear, culture, and polymerase chain reaction (PCR) assay for G. vaginalis. Results: The microscopic method detected high frequency of BV in symptomatic (57%) whereas only a minority of asymptomatic subjects (14%) were detected. G. vaginalis-associated BV was diagnosed in approximately equal proportions when evaluated with PCR and microscopic method for both pregnant and nonpregnant women. The comparative analysis of microscopic evaluation, culture and PCR assays demonstrated greater concurrence (about 90%) between Gram staining and PCR detection for BV, than both methods compared to culture. The combination of microscopy and PCR turned out to be very reliable and repeatable for detecting G. vaginalis-associated BV. Conclusions: This is the first comparative investigation on the epidemiology of G. vaginalis-associated BV in Bulgaria. The established highest frequency in the young Bulgarian women (21–30 years) is alarming and should be considered in prophylaxis and reproductive programmes. Keywords: Bacterial vaginosis, Gardnerella vaginalis, Bulgarian women

9. Immunoglobulin levels, cytology and microbiologic investigations of broncho-alveolar lavage in children with cystic fibrosis

Author

Tanya Strateva, Nikolay Ulevinov, Penka Perenovska, and Guergana Petrova

Subjects
Microbiology (medical), Pathology, medicine.medical_specialty, Staphylococcus aureus, Immunoglobulin levels, Adolescent, Cystic Fibrosis, lcsh:QR1-502, Immunoglobulins, Cystic fibrosis, Severity of Illness Index, Broncho-alveolar lavage, lcsh:Microbiology, lcsh:Infectious and parasitic diseases, Cytology, medicine, Humans, lcsh:RC109-216, Child, Medicine(all), business.industry, medicine.disease, Infectious Diseases, Case-Control Studies, Child, Preschool, Pseudomonas aeruginosa, business, Bronchoalveolar Lavage Fluid

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