scholarly journals Increasing macrolide resistance among Streptococcus agalactiae causing invasive disease in non-pregnant adults was driven by a single capsular-transformed lineage, Portugal, 2009 to 2015

2018 ◽  
Vol 23 (21) ◽  
Author(s):  
Elísia Lopes ◽  
Tânia Fernandes ◽  
Miguel P Machado ◽  
João André Carriço ◽  
José Melo-Cristino ◽  
...  
Keyword(s):  
Antimicrobial Susceptibility ◽  
Recombination Event ◽  
Surface Protein ◽  
Invasive Disease ◽  
Macrolide Resistance ◽  
Gene Profiling ◽  
Genetic Lineage ◽  
Group B ◽  
Resistance Rates ◽  
Lancefield Group

We characterised Lancefield group B streptococcal (GBS) isolates causing invasive disease among non-pregnant adults in Portugal between 2009 and 2015. All isolates (n = 555) were serotyped, assigned to clonal complexes (CCs) by multilocus sequence typing and characterised by surface protein and pilus island gene profiling. Antimicrobial susceptibility was tested by disk diffusion and resistance genotypes identified by PCR. Overall, serotype Ia was most frequent in the population (31%), followed by serotypes Ib (24%) and V (18%). Serotype Ib increased significantly throughout the study period (p < 0.001) to become the most frequent serotype after 2013. More than 40% of isolates clustered in the CC1/alp3/PI-1+PI-2a genetic lineage, including most isolates of serotypes Ib (n = 110) and V (n = 65). Erythromycin and clindamycin resistance rates were 35% and 34%, respectively, both increasing from 2009 to 2015 (p < 0.010) and associated with CC1 and serotype Ib (p < 0.001). The Ib/CC1 lineage probably resulted from acquisition of the type Ib capsular operon in a single recombination event by a representative of the V/CC1 macrolide-resistant lineage. Expansion of the new serotype Ib/CC1 lineage resulted in increased macrolide resistance in GBS, causing invasive disease among adults in Portugal. The presence of this clone elsewhere may predict more widespread increase in resistance.

scholarly journals Evidence for Rare Capsular Switching in Streptococcus agalactiae

2009 ◽  
Vol 192 (5) ◽  
pp. 1361-1369 ◽  
Author(s):  
Elisabete Raquel Martins ◽  
José Melo-Cristino ◽  
Mário Ramirez
Keyword(s):  
Streptococcus Agalactiae ◽  
Group B Streptococcus ◽  
Surface Protein ◽  
Gene Profiling ◽  
Critical Importance ◽  
Vaccination Strategies ◽  
Antigenic Factor ◽  
Group B ◽  
Lancefield Group

ABSTRACT The polysaccharide capsule is a major antigenic factor in Streptococcus agalactiae (Lancefield group B streptococcus [GBS]). Previous observations suggest that exchange of capsular loci is likely to occur rather frequently in GBS, even though GBS is not known to be naturally transformable. We sought to identify and characterize putative capsular switching events, by means of a combination of phenotypic and genotypic methods, including pulsed-field gel electrophoretic profiling, multilocus sequence typing, and surface protein and pilus gene profiling. We show that capsular switching by horizontal gene transfer is not as frequent as previously suggested. Serotyping errors may be the main reason behind the overestimation of capsule switching, since phenotypic techniques are prone to errors of interpretation. The identified putative capsular transformants involved the acquisition of the entire capsular locus and were not restricted to the serotype-specific central genes, the previously suggested main mechanism underlying capsular switching. Our data, while questioning the frequency of capsular switching, provide clear evidence for in vivo capsular transformation in S. agalactiae, which may be of critical importance in planning future vaccination strategies against this pathogen.

Association between maternal Group B Streptococcus surface-protein antibody concentrations and invasive disease in their infants

2015 ◽  
Vol 14 (12) ◽  
pp. 1651-1660 ◽  
Author(s):  
Ziyaad Dangor ◽  
Gaurav Kwatra ◽  
Alane Izu ◽  
Peter Adrian ◽  
Clare L Cutland ◽  
...  
Keyword(s):  
Group B Streptococcus ◽  
Surface Protein ◽  
Invasive Disease ◽  
Group B

Population genomics reveals distinct temporal association with the emergence of ST1 serotype V Group B Streptococcus and macrolide resistance in North America

2021 ◽  
Author(s):  
M. Belén Cubria ◽  
Luis Alberto Vega ◽  
William C. Shropshire ◽  
Misu A. Sanson ◽  
Brittany J. Shah ◽  
...  
Keyword(s):  
Population Genomics ◽  
Young Infant ◽  
Mobile Genetic Elements ◽  
Invasive Disease ◽  
Macrolide Resistance ◽  
Temporal Association ◽  
Bacterial Disease ◽  
Genetic Elements ◽  
Young Infants ◽  
Group B

Identified in the 1970s as the leading cause of invasive bacterial disease in neonates and young infants, Group B Streptococcus (GBS) is now also recognized as a significant cause of morbidity and mortality among adults with underlying medical conditions and the elderly. Concomitant with the increasing incidence of GBS invasive disease in adults is the rise of resistance among GBS isolates to second line antibiotics. Previous research shows that among serotype V GBS – one of the most common capsular types causing adult invasive disease – sequence type 1 (ST1) – accounts for an overwhelming majority of adult invasive disease isolates and frequently harbors macrolide resistance. In this study, using whole genome sequencing data from strains isolated in the USA and Canada over a 45-year period, we examined the association of antimicrobial resistance with the emergence of invasive serotype V ST1 GBS. Our findings show a strong temporal association between increased macrolide resistance and the emergence of serotype V ST1 GBS subpopulations that currently co-circulate to cause adult as well as young infant invasive disease. ST1 GBS subpopulations are defined, in part, by the presence of macrolide resistance genes in mobile genetic elements. Increased frequency of macrolide resistance-encoding mobile genetic elements among invasive GBS ST1 strains suggests the presence of such elements contributes to GBS virulence. Our work provides a foundation for the investigation of genetic features contributing to the increasing prevalence and pathogenesis of serotype V GBS in adult invasive disease.

scholarly journals Antimicrobial Susceptibilities of Group B Streptococci Isolated from Patients with Invasive Disease: 10-Year Perspective

2001 ◽  
Vol 45 (12) ◽  
pp. 3623-3624 ◽  
Author(s):  
David R. Murdoch ◽  
L. Barth Reller
Keyword(s):  
Antimicrobial Susceptibility ◽  
Susceptibility Testing ◽  
Invasive Disease ◽  
Antimicrobial Susceptibility Testing ◽  
Streptococcal Infections ◽  
Group B Streptococci ◽  
Treatment And Prevention ◽  
Group B ◽  
High Level ◽  
Level Resistance

ABSTRACT Antimicrobial susceptibility testing of 192 group B streptococcal isolates from patients with invasive disease demonstrated that 31 (16%) were resistant to erythromycin and 17 (9%) were resistant to clindamycin. One isolate demonstrated high-level resistance to streptomycin, but none was highly resistant to gentamicin. Erythromycin and clindamycin are no longer reliable empirical alternatives to penicillin for the treatment and prevention of group B streptococcal infections.

scholarly journals Emergence of Serotype IV Group B Streptococcus Adult Invasive Disease in Manitoba and Saskatchewan, Canada, Is Driven by Clonal Sequence Type 459 Strains

2015 ◽  
Vol 53 (9) ◽  
pp. 2919-2926 ◽  
Author(s):  
Sarah Teatero ◽  
Taryn B. T. Athey ◽  
Paul Van Caeseele ◽  
Greg Horsman ◽  
David C. Alexander ◽  
...  
Keyword(s):  
Antimicrobial Susceptibility ◽  
Group B Streptococcus ◽  
The United States ◽  
Invasive Disease ◽  
Sequence Type ◽  
Polymorphism Analysis ◽  
Invasive Infection ◽  
Content Type ◽  
Total Burden ◽  
Group B

Serotype IV group BStreptococcus(GBS) is emerging in Canada and the United States with rates as high as 5% of the total burden of adult invasive GBS disease. To understand this emergence, we studied the population structure and assessed the antimicrobial susceptibility of serotype IV isolates causing adult invasive infection in Manitoba and Saskatchewan, Canada, between 2010 and 2014. Whole-genome sequencing was used to determine multilocus sequence typing information and identify genes encoding antimicrobial resistance in 85 invasive serotype IV GBS strains. Antimicrobial susceptibility testing was performed by standard methods. Strain divergence was assessed using genome-wide single-nucleotide polymorphism analysis. Serotype IV strains were responsible for 16.9% of adult invasive GBS infections in Manitoba and Saskatchewan during the period. The majority of serotype IV isolates (89%) were clonally related, tetracycline-, erythromycin-, and clindamycin-resistant sequence type 459 (ST459) strains that possessed genestetMandermTR. Genome comparisons between ST459 and serotype V ST1 GBS identified several areas of recombination in an overall similar genomic background. Serotype IV ST459 GBS strains are expanding and causing a substantial percentage of adult invasive GBS disease. This emergence may be linked to the acquisition of resistance to tetracycline, macrolides, and lincosamides.

scholarly journals Genetic characterization and diversity of Streptococcus agalactiae isolates with macrolide resistance

2010 ◽  
Vol 59 (7) ◽  
pp. 780-786 ◽  
Author(s):  
Monika Brzychczy-Włoch ◽  
Tomasz Gosiewski ◽  
Małgorzata Bodaszewska ◽  
Wojciech Pabian ◽  
Małgorzata Bulanda ◽  
...  
Keyword(s):  
Streptococcus Agalactiae ◽  
Group B Streptococcus ◽  
Surface Protein ◽  
Macrolide Resistance ◽  
Surface Proteins ◽  
Erythromycin Resistance ◽  
High Genetic Diversity ◽  
Genes Encoding ◽  
Resistant Strains ◽  
Group B

Macrolide resistance in 169 Streptococcus agalactiae [group B streptococcus (GBS)] isolates originating from pregnant carriers was investigated. Using multiplex PCR the presence of genes encoding erythromycin resistance and capsular polysaccharides, as well as surface proteins, was determined. Random amplification of polymorphic DNA (RAPD) and PFGE were used to characterize specific clones among the isolates. In the examined population of women, erythromycin-resistant strains were found in 4.5 % of patients, whereas clindamycin-resistant strains were found in 3 % of patients, which was 16 % of strains resistant to erythromycin and 10 % of strains resistant to clindamycin among GBS isolates, respectively. Among the isolates, the largest percentage was represented by the constitutive macrolide–lincosamide–streptogramin B (cMLSB) phenotype (63 %), then the inductive macrolide–lincosamide–streptogramin B (iMLSB) phenotype (26 %) and the macrolide resistance (M) phenotype (11 %). The ermB gene was indicated in all isolates with the cMLSB phenotype and V serotype, whereas mefA/mefE genes were found in isolates with the M phenotype and Ia serotype. Among resistance isolates, serotype V was predominant (67 %), followed by serotypes II (15 %), Ia (11 %) and III (7 %). The most common surface protein encoding genes were alp3 (70 %), then rib (11 %), epsilon (7.5 %), bca (7.5 %) and alp2 (4 %). A statistically significant relationship between macrolide resistance, serotype V and the alp3 gene was demonstrated. PFGE, in comparison to the RAPD method, gave better genetic discrimination of GBS isolates. A relatively high genetic diversity among investigated strains was shown. In addition, the largest genetic homogeneity was found in serotype V.

scholarly journals Emergence of Invasive Serotype Ib Sequence Type 10 Group B Streptococcus Disease in Chinese Infants Is Driven by a Tetracycline-Sensitive Clone

2021 ◽  
Vol 11 ◽  
Author(s):  
Li Zhang ◽  
Wen-Juan Kang ◽  
Lei Zhu ◽  
Li-Jun Xu ◽  
Chao Guo ◽  
...  
Keyword(s):  
Late Onset ◽  
Medical Center ◽  
Group B Streptococcus ◽  
Surface Protein ◽  
Sequence Type ◽  
Genetic Lineage ◽  
Clinical Complications ◽  
Invasive Infections ◽  
Severe Infections ◽  
Group B

BackgroundGroup B streptococcus (GBS) is a leading cause of serious infections in infants. The extensive use of tetracycline has led to the selection of specific resistant and infectious GBS clones. The sequence type (ST) 10 GBS strain, causing invasive infections in infants, is becoming prevalent in China. We aimed to understand the clinical and microbiological characteristics of this GBS strain.MethodsWe conducted a retrospective study on infants with invasive GBS disease from the largest women’s and children’s medical center in Shanxi and collected data between January 2017 and October 2020. GBS isolates were analyzed by capsule serotyping, genotyping, antibiotic resistance, and surface protein genes.ResultsAll ST10 isolates belonged to serotype Ib; type Ib/ST10 strains were responsible for 66.7% (14/21, P &lt; 0.05) of infant invasive GBS infections during the period and all resulted in late-onset (LOD) and late LOD disease (14/14). Infants with type Ib/ST10 GBS disease had significantly higher rates of meningitis (9/14, 64.3%, p &lt; 0.05) and clinical complications (5/14, 35.7%, p &lt; 0.05). The Ib/ST10 GBS isolates had limited genetic diversity, clustered in the CC10/bca/PI-1 + PI-2a genetic lineage, showed resistance to erythromycin, lincomycin, and fluoroquinolones and sensitivity to tetracycline, and possessed genes ermT, ermB, and amino acid changes in gyrA and parC.ConclusionsThe probable clonal expansion can result in severe infections in infants and ongoing emergence of multi-drug resistant isolates. Continued monitoring for type Ib/ST10 GBS infections is warranted.

scholarly journals Active and Passive Intranasal Immunizations with Streptococcal Surface Protein C5a Peptidase Prevent Infection of Murine Nasal Mucosa-Associated Lymphoid Tissue, a Functional Homologue of Human Tonsils

2005 ◽  
Vol 73 (12) ◽  
pp. 7878-7886 ◽  
Author(s):  
Hae-Sun Park ◽  
P. Patrick Cleary
Keyword(s):  
Nasal Mucosa ◽  
Lymphoid Tissue ◽  
Streptococcal Infection ◽  
Surface Protein ◽  
Effective Vaccine ◽  
Infection Model ◽  
Loss Of Function ◽  
Intranasal Immunization ◽  
Endemic Disease ◽  
Group B

ABSTRACT C5a peptidase, also called SCPA (surface-bound C5a peptidase), is a surface-bound protein on group A streptococci (GAS), etiologic agents for a variety of human diseases including pharyngitis, impetigo, toxic shock, and necrotizing fasciitis, as well as the postinfection sequelae rheumatic fever and rheumatic heart disease. This protein is highly conserved among different serotypes and is also expressed in human isolates of group B, C, and G streptococci. Human tonsils are the primary reservoirs for GAS, maintaining endemic disease across the globe. We recently reported that GAS preferentially target nasal mucosa-associated lymphoid tissue (NALT) in mice, a tissue functionally analogous to human tonsils. Experiments using a C5a peptidase loss-of-function mutant and an intranasal infection model showed that this protease is required for efficient colonization of NALT. An effective vaccine should prevent infection of this secondary lymphoid tissue; therefore, the potential of anti-SCPA antibodies to protect against streptococcal infection of NALT was investigated. Experiments showed that GAS colonization of NALT was significantly reduced following intranasal immunization of mice with recombinant SCPA protein administered alone or with cholera toxin, whereas a high degree of GAS colonization of NALT was observed in control mice immunized with phosphate-buffered saline only. Moreover, administration of anti-SCPA serum by the intranasal route protected mice against streptococcal infection. These results suggest that intranasal immunization with SCPA would prevent colonization and infection of human tonsils, thereby eliminating potential reservoirs that maintain endemic disease.

Sign in / Sign up

Export Citation Format

Share Document