Introduction: Group B Streptococcus (GBS), infection and recurrence in newborns and pregnant women can lead to chronic medical illness resulting in significant morbidity, and mortality. Pathogenesis of GBS may be due to reasons such as activation of the immune system, followed by the production of inflammatory markers and toxic components by immune cells including macrophages. Methods: The studies on invasive and colonizing GBS strains inoculated either with peripheral or brain macrophages, the expression of nitric oxide (NO), cell viability, and CD40 were also measured by Griess assay, methyl tetrazolium assay (MTT), and flow cytometry, respectively. Furthermore, the clinical manifestations of the selected patients were also assessed for this study. Results: Outcome of inflammatory markers studies, after GBS inoculation indicated that, invasive GBS strains induced higher inflammatory markers in comparison to colonizing GBS strains. Furthermore, patients’ clinical data showed that patients with invasive GBS infections had severe condition unlike among patients with colonizing GBS strains. The fatality rate in patients with invasive GBS strain were 30.8% while there was no death among carriers. Conclusion: This study, aimed to understand the immune response to GBS, and strengthen the knowledge on GBS pathogenesis. It was concluded that invasive GBS strains not only showed higher expression of inflammatory markers on immune cells but also had higher pathogenesis effect in comparison to colonizing GBS strains.
Streptococcus agalactiae ; Pregnancy

Aims: Maternal vaginal Group B Streptococcus (GBS) colonization is considered a risk factor for preterm delivery and, consequently, neonatal infections. Previous studies have portrayed the important roles of these virulence factors, including hemolytic pigment, hyaluronidase (HylB), serine-rich protein (Srr) and bacterial surface adhesion of GBS (BsaB) in mediating GBS colonization and intrauterine ascending infection, causing preterm delivery. This study aimed to investigate the association between mRNA expression of virulence genes in GBS isolates obtained from symptomatic pregnant women and preterm delivery. Methodology and results: GBS isolates were obtained from high vaginal swabs of 40 symptomatic pregnant women of gestational age of less than 37 weeks. RNA was extracted from these GBS isolates and RT-qPCR was performed to determine the relative mRNA expression of GBS virulence genes, including CylE (encode enzyme required for the biosynthesis of the hemolytic pigment), HylB, Srr-1 and BsaB. Socio-demographic details and obstetric history were not found to be associated with the delivery outcomes of these women. The GBS isolates from symptomatic pregnant women who delivered prematurely showed a higher expression of CylE gene and a trend towards an elevated expression of HylB gene compared to women with term delivery. Meanwhile the expression of both Srr-1 and BsaB genes was similar between symptomatic pregnant women who had term or preterm delivery. Conclusion, significance and impact of study The results suggest that following vaginal colonization, both CylE and HylB genes are likely to contribute to intrauterine ascending infection and inflammation, leading to preterm delivery in humans. These virulence factors may be targeted for the pre-clinical stages of vaccine development or therapeutic intervention.
Streptococcus agalactiae--isolation & ; purification ; Pregnant Women

Streptococcal toxic shock syndrome (STSS) is an acute, progressive illness that manifests with fever, hypotension, and accelerated multi-organ failure. It is usually caused by Group A Streptococcus (Streptococcus pyogenes). STSS due to non-group A streptococci is rare, but its incidence has recently increased. We report here on two cases of STSS caused by Group B Streptococcus (Streptococcus agalactiae) and Group G Streptococcus (Streptococcus dysagalactiae).
Fever ; Hypotension ; Incidence ; Shock, Septic ; Streptococcus ; Streptococcus agalactiae

Genotype ; Humans ; Streptococcal Infections ; diagnosis ; microbiology ; Streptococcus agalactiae ; genetics

BACKGROUND: Group B Streptococcus (GBS) is known to be the leading cause of severe neonatal infections and also causes infections in pregnant women and adults with chronic underlying diseases. The frequency of GBS infections has increased recently. This study was aimed to determine the cultural results of beta-hemolytic streptococci and the clinical significance of the patients who had GBS infections during recent years. METHODS: This study has analyzed the isolation results and clinical importance of beta-hemolytic streptococci and GBS isolated from clinical specimens, except for stools, obtained from the patients in the Severance Hospital in Seoul from 1991 to 1999. RESULTS: Of 2,242 isolated beta-hemolytic streptococci, clinical records of 2,078 were available. GBS was found in 790 cases (38.0%). The isolation rate of group A Streptococcus was considerably high in pus and respiratory specimens while GBS was most commonly isolated from urogenital specimens. The isolation rate of GBS was much higher in females than males. GBS was the most common in patients under the age of one year or over age twenty. Especially, in newborn babies, GBS accounted for 72.7% of the total isolates. Of the 790 GBS isolates, 35.6% were considered to have definite infections. Of the 283 GBS infected patients, 56.2% had chronic diseases such as diabetes and malignancies. CONCLUSIONS: GBS is, two-fold, more commonly isolated than group A Streptococcus and the isolation rate is on the rise. GBS is more common in adult patients with chronic underlying diseases and remarkably high in newborn babies and the neonatal infections are severe. Therefore, microbiological diagnosis of GBS infections is necessary for proper treatment.
Adult ; Chronic Disease ; Diagnosis ; Female ; Humans ; Infant, Newborn ; Male ; Pregnant Women ; Seoul ; Streptococcus agalactiae ; Streptococcus* ; Suppuration

BACKGROUND: Invasive Streptococcus agalactiae (group B streptococcus, GBS) infection most commonly occurs in infants; however, cases of GBS infection in adults, particularly in the elderly with significant underlying diseases, are being increasingly reported. We analyzed the serotype specific opsonophagocytic antibodies (the major mechanism of protection against GBS) in infants, adults, and the elderly. METHODS: The opsonization indices (OIs) of antibodies against serotype Ia, Ib, II, III, and V GBS were studied in 89 infants, 35 adults (age, 30–50 years), and 62 elderly individuals (age, 65–85 years) according to the University of Alabama at Birmingham GBS opsonophagocytic killing assay protocol (www.vaccine.uab.edu). RESULTS: In infants, adults, and elderly groups respectively, geometric mean of OI against GBS serotype Ia were 3, 7, and 32; against GBS serotype Ib were 7, 242, and 252; against serotype II were 93, 363, and 676; against serotype III were 8, 212, and 609; and against serotype V were 4, 639, and 610. The seropositive rate (% of subjects with OI ≥ 4) increased significantly in older age group for all five serotypes. CONCLUSION: During infancy, only a limited proportion of infants have functional immunity against serotype Ia, Ib, II, III, and V GBS. Furthermore, a lack of opsonic activities against GBS observed in some adults and the elderly might predispose such individuals to the risk of invasive GBS infection. Epidemiological monitoring and development of suitable vaccine for these populations are needed.
Adult ; Aged ; Alabama ; Antibodies* ; Epidemiological Monitoring ; Homicide ; Humans ; Infant ; Prevalence ; Seroepidemiologic Studies* ; Serogroup* ; Streptococcus agalactiae ; Streptococcus*

Group B streptococcus (GBS) is the leading cause of neonatal morbidity and mortality. Late-onset GBS disease commonly manifests as occult bacteremia or meningitis. Approximately 50% of survivors of late-onset meningitis have long-term neurologic sequelae. Cerebrovascular complications are often associated with unfavorable clinical outcomes of GBS meningitis. There have been a few reports of cerebral infarction accompanied by GBS meningitis. We report a 29-day-old girl with severe, widespread cerebral infarction due to late-onset GBS meningitis. Isolated GBS strain from this patient was serotype III, ST-19. Currently, she has cortical blindness and significant developmental delay.
Bacteremia ; Blindness, Cortical ; Cerebral Infarction ; Female ; Humans ; Meningitis ; Mortality ; Serogroup ; Streptococcus ; Streptococcus agalactiae ; Survivors

We describe here a 26-year-old woman who presented confusion and right hemiparesis due to embolic obstruction of left internal carotid artery and middle cerebral artery. Transthoracic echocardiography showed structurally normal mitral valve with hypermobile echogenic material suggesting vegetation. The vegetation was disappeared after antimicrobial treatment without surgery.
Adult ; Carotid Artery, Internal ; Echocardiography ; Endocarditis ; Female ; Humans ; Middle Cerebral Artery ; Mitral Valve ; Paresis ; Streptococcus ; Streptococcus agalactiae ; Stroke

Group B streptococcus (GBS) infection is a leading cause of sepsis and meningitis among infants, and is associated with high rates of morbidity and mortality in many countries. Protection against GBS typically involves antibody-mediated opsonization by phagocytes and complement components. The present study evaluated serotype-specific functional antibodies to GBS among Korean infants and in intravenous immunoglobulin (IVIG) products. An opsonophagocytic killing assay (OPA) was used to calculate the opsonization indices (OIs) of functional antibodies to serotypes Ia, Ib, and III in 19 IVIG products from 5 international manufacturers and among 98 Korean infants (age: 0–11 months). The GBS Ia, Ib, and III serotypes were selected because they are included in a trivalent GBS vaccine formulation that is being developed. The OI values for the IVIG products were 635–5,706 (serotype Ia), 488–1,421 (serotype Ib), and 962–3,315 (serotype III), and none of the IVIG lots exhibited undetectable OI values (< 4). The geometric mean OI values were similar for all 3 serotypes when we compared the Korean manufacturers. The seropositive rate among infants was significantly lower for serotype Ia (18.4%), compared to serotype Ib and serotype III (both, 38.8%). Infant age of ≥ 3 months was positively correlated with the seropositive rates for each serotype. Therefore, only a limited proportion of infants exhibited protective immunity against serotype Ia, Ib, and III GBS infections. IVIG products that exhibit high antibody titers may be a useful therapeutic or preventive measure for infants. Further studies are needed to evaluate additional serotypes and age groups.
Antibodies* ; Complement System Proteins ; Homicide ; Humans ; Immunoglobulins* ; Immunoglobulins, Intravenous ; Infant* ; Meningitis ; Mortality ; Opsonin Proteins ; Phagocytes ; Sepsis ; Serogroup* ; Streptococcus agalactiae ; Streptococcus*

Toxic shock syndrome is an acute and febrile illness that rapidly progress to shock and multi-organ failure, and it is caused by toxin-producing strains of Staphylococcus aureus or Streptococcus species. Streptococcal toxic shock syndrome (STSS) is usually caused by group A streptococci, but non-group A STSS is rare. In this study, we describe a case of STSS caused by Streptococcus agalactiae(group B streptococci) in a patient with alcoholic liver cirrhosis. At arrival in our hospital, the patient had a decreased mental status with hemorrhagic bullae on four extremities, and he progressed to a fatal outcome within 4 days in spite of antibiotic treatment.
Extremities ; Fatal Outcome ; Humans ; Liver Cirrhosis ; Liver Cirrhosis, Alcoholic ; Shock ; Shock, Septic ; Staphylococcus aureus ; Streptococcus ; Streptococcus agalactiae