head JofIMAB
Journal of IMAB - Annual Proceeding (Scientific Papers)
Publisher: Peytchinski Publishing Ltd.
ISSN: 1312-773X (Online)
Issue: 2020, vol. 26, issue2
Subject Area: Medicine
DOI: 10.5272/jimab.2020262.3203
Published online: 22 June 2020

Original article

J of IMAB. 2020 Apr-Jun;26(2):3203-3207
Adile MuhtarovaORCID logo Corresponding Autoremail, Raina GergovaORCID logo, Ivan MitovORCID logo,
Department of Medical Microbiology, Faculty of Medicine, Medical University - Sofia, Bulgaria.

Purpose: This study aims to determine the virulence profile of the circulating Bulgarian clinical isolates of  GBS including the highly virulent serotype III by molecular methods and evaluate the differences among studied isolates from healthy pregnant women and non-pregnant ill persons.
Material and methods: We investigated 104 non-duplicate isolates of GBS obtained from pregnant (n=15) and non-pregnant women (n=89), living in Sofia, Bulgaria. All GBS strains were screened for the presence of important virulence genes, namely bca, cyl(E), rib, hyl(B) and the capsular serotype III detected by Real-time PCR.
Results: PCR detection of five important virulence genes showed that cylE (91.3%) was the most prevalent one among the total isolates of GBS. Genes encoding the C protein (bca), hyaluronate lyase (hylB), Alp family protein Rib (rib) were presented in 51%, 17.3% and 22.1% respectively of the examined isolates. By using real-time PCR, we found that 13.5% from all tested Bulgarian GBS strains confirmed as GBS serotype III and harbored cpsI gene. No significant differences between the two groups were observed excluding the presence of cpsI.
Conclusion: The risk of neonatal and prenatal GBS infection in 1/3 of healthy pregnant women colonized by streptococcal strains with highly virulent capsular serotype in combination with other strong virulent factors was demonstrated by this study. The regular screening for GBS and properly treatment could be reduce the severe maternal-fetal infections due to this microorganism.

Keywords: Streptococcus agalactiae, PCR, virulence factors,

pdf - Download FULL TEXT /PDF 776 KB/
Please cite this article as: Muhtarova A, Gergova R, Mitov I. Virulence profile of Bulgarian clinical isolates Streptococcus agalactiae - PCR determination. J of IMAB. 2020 Apr-Jun;26(2):3203-3207. DOI: 10.5272/jimab.2020262.3203

Corresponding AutorCorrespondence to: Adile Muhtarova, Department of Medical Microbiology, Faculty of Medicine, Medical University of Sofia; 2, Zdrave Str., 1431 Sofia, Bulgaria; E-mail: adimuhtarova@gmail.com

1. Seng P, Vernier M, Gay A, Pinelli PO, Legré R, Stein A. Clinical features and outcome of bone and joint infections with streptococcal involvement: 5-year experience of interregional reference centres in the south of France. New Microbes New Infect. 2016 Apr 13;12:8-17. [PubMed] [Crossref]
2. Maisey H, Doran K, Nizet V. Recent advances in understanding the molecular basis of group B Streptococcus virulence. Expert Rev Mol Med. 2008 Sep 22;10:e27. [PubMed] [Crossref]   
3. Moore MR, Schrag SJ, Schuchat A. Effects of Intrapartum Antimicrobial Prophylaxis for Prevention of group-B-streptococcal Disease on the Incidence and Ecology of Early-Onset Neonatal Sepsis. Lancet Infect Dis. 2003 Apr;3(4):201-13. [PubMed] [Crossref]
4. Eskandarian N, Ismail Z, Neela V, van Belkum A, Desa MN, Amin Nordin S. Antimicrobial susceptibility profiles, serotype distribution and virulence determinants among invasive, non-invasive and colonizing Streptococcus agalactiae (group B streptococcus) from Malaysian patients. Eur J Clin Microbiol Infect Dis. 2015 Mar;34(3):579-84. [PubMed]  [Crossref]
5. Sendi P, Johansson L, Norrby-Teglund A. Invasive group B Streptococcal disease in non-pregnant adults : a review with emphasis on skin and soft-tissue infections. Infection. 2008 Mar;36(2):100-11. [PubMed] [Crossref]
6. Slotved H, Kong F, Lambertsen L, Sauer S, Gilbert GL. Serotype IX, a Proposed New Streptococcus agalactiae Serotype. J Clin Microbiol. 2007 Sep;45(9):2929-36. [PubMed] [Crossref]
7. Madzivhandila M, Adrian PV, Cutland CL, Kuwanda L, Schrag SJ, Madhi SA. Serotype distribution and invasive potential of group B streptococcus isolates causing disease in infants and colonizing maternal-newborn dyads. PLoS One. 2011 Mar 21;6(3):e17861. [PubMed]  [Crossref]
8. Seifert KN, Adderson EE, Whiting AA, Bohnsack JF, Crowley PJ, Brady LJ. A unique serine-rich repeat protein (Srr-2) and novel surface antigen (epsilon) associated with a virulent lineage of serotype III Streptococcus agalactiae. Microbiology. 2006 Apr;152(Pt 4):1029-40. [PubMed] [Crossref]
9. Lazzarin M, Mu R, Fabbrini M, Ghezzo C, Rinaudo CD, Doran KS, Margarit I. Contribution of pilus type 2b to invasive disease caused by a Streptococcus agalactiae ST-17 strain. BMC Microbiol. 2017 Jul 3;17(1):148.  [PubMed] [Crossref]
10. Six A, Bellais S, Bouaboud A, Fouet A, Gabriel C, Tazi A, et al. Srr2, a multifaceted adhesin expressed by ST-17 hypervirulent Group B Streptococcus involved in binding to both fibrinogen and plasminogen. Mol Microbiol. 2015 Sep;97(6):1209-22. [PubMed] [Crossref]
11. Breeding KM, Ragipani B, Lee KD, Malik M, Randis TM, Ratner AJ. Real-time PCR-based serotyping of Streptococcus agalactiae. Sci Rep. 2016 Dec 2;6:38523. [PubMed] [Crossref
12. Creti R, Fabretti F, Orefici G, von Hunolstein C. Multiplex PCR assay for direct identification of group B streptococcal alpha-protein-like protein genes. J Clin Microbiol. 2004 Mar;42(3):1326-9.[PubMed] [Crossref]
13. Hensler ME, Miyamoto S, Nizet V. Group B streptococcal beta-hemolysin/cytolysin directly impairs cardiomyocyte viability and function. PLoS One. 2008 Jun 18;3(6):e2446. [PubMed] [Crossref]
14. Madoff L, Michel J, Gong E, Kling D, Kasper D. Group B streptococci escape host immunity by deletion of tandem repeat elements of the alpha C protein. Proc Natl Acad Sci U S A. ;1996 Apr 30;93(9):4131-6. [PubMed] [Crossref]
15. López Y, Parra E, Cepas V, Sanfeliú I, Juncosa T, Andreu A, et al.  Serotype, virulence profile, antimicrobial resistance and macrolide-resistance determinants in Streptococcus agalactiae isolates in pregnant women and neonates in Catalonia, Spain. Enferm Infecc Microbiol Clin. 2018 Oct;36(8):472-477. [PubMed] [Crossref]
 16. Nie S, Lu X, Jin Z, Gao J, Ma D, Deng J, et al. Characterization of group B Streptococcus isolated from sterile and non-sterile specimens in China. Diagn Microbiol Infect Dis. 2018 Sep;92(1):56-61. [PubMed] [Crossref]
17. Beigverdi R, Jabalameli F, Mirsalehian A, Hantoushzadeh S, Boroumandi S, Taherikalani M, et al. Virulence factors, antimicrobial susceptibility and molecular characterization of Streptococcus agalactiae isolated from pregnant women. Acta Microbiol Immunol Hung. 2014 Dec;61(4):425-34. [PubMed] [Crossref]
18. Edmond K, Kortsalioudaki C, Scott S, Schrag S, Zaidi A, Cousens S, et al. Group B streptococcal disease in infants aged younger than 3 months: systematic review and meta-analysis. Lancet. 2012 Feb 11;379(9815):547-56. [PubMed]  [Crossref]
19. Russell N, Seale A, O’Driscoll M, O’Sullivan C, Bianchi-Jassir F, Gonzalez-Guarin J, et al. Maternal Colonization With Group B Streptococcus and Serotype Distribution Worldwide: Systematic Review and Meta-analyses. Clin Infect Dis. 2017 Nov 6;65(suppl_2):S100-S111. [PubMed] [Crossref]
20. Gajic I, Plainvert C, Kekic D, Dmytruk N, Mijac V, Tazi A, et al. Molecular epidemiology of invasive and non-invasive group B Streptococcus circulating in Serbia. Int J Med Microbiol. 2019 Jan;309(1):19-25. [PubMed] [Crossref]
21. Todorova-Christova M, Vacheva R, Decheva A, Nikolov A, Slancheva B, Stoichkova D, et al. A study on early-onset neonatal group B streptococcal infection, Bulgaria, 2007-2011. Arch Pediatr. 2014 Sep;21(9):953-60. [PubMed] [Crossref].

Received: 01 August 2019
Published online: 22 June 2020

back to Online Journal