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PubMedDate not supplied

[Colonization by Streptococcus group B in full term pregnancy and newborns in a community in Venezuela].

BACKGROUND: The aim of this study was to define the incidence of cervico-vaginal colonization by group B Streptococcus (SGB) in full term pregnancy as well as vertical and horizontal transmission in newborns attended in two public hospitals in Valencia, Venezuela. METHODS: An study cervico-vaginal exudates from 171 full term pregnant women was performed together with general obstetric survey. Oropharyngeal and nasal exudate studies in 118 newborns of the mothers studied were carried out during the first 12 hours after birth as was a neonatologic survey. RESULTS: The global percentage of maternal colonization by SGB were 32.7% while in the NB it was 45.8%. Among the NB colonized by SGB 73.2% were considered to have acquired the bacteria from the mother (vertical) with no significant differences in the data found in the two hospitals. The rate of horizontal colonization of the newborns was 42.3% in one hospital and only 8% in the second. CONCLUSIONS: There were no significant statistical differences between the rate of cervico-vaginal colonization in women attended in two public hospitals in Venezuela. No differences were observed in the rate of vertical colonization of newborns but to the contrary, that of the horizontal (nosocomial) colonization was of 42.3% and 8% in the Charity and University Hospitals, respectively.

Cervix Mucus↗

PubMedDate not supplied

[The characteristics of the immune response to the polysaccharide determinants of Streptococcus group A in rheumatism].

As shown in this study, the formation of antibodies, at least, to the determinants (DT) of polysaccharide of group A streptococcus (A-PS), common with epidermal antigens, occurs in rheumatic fever. Two DT include N-acetylglucosamine; DT common with epidermal basal cell antigen (DT-1) and DT common with antigen of the perinuclear zone of the cytoplasm of cells of differentiated layers (DT-2). Two other DT seem to contain only rhamnose; DT common with the cytoplasm of cells of differentiated layers (DT-3) and DT common with epidermal antigen, characteristic of the cytoplasm of cells of all epidermal layers (DT-4). Conclusion has been made that the presence of autoantibodies to epidermal basal cell antigens, common with DT-1 and DT-4 of A-PS, may serve as an additional indicator of the activity of the rheumatic process. Autoantibodies to cross-reacting DT-4 of A-PS are indicative of the chronization of the process with a tendency to relapses of rheumatic fever.

Acetylglucosamine↗

PubMed2005

Comparison of a 3-set genotyping system with multilocus sequence typing for Streptococcus agalactiae (Group B Streptococcus).

Group B streptococcus (GBS; Streptococcus agalactiae) is the most common cause of neonatal and obstetric sepsis and is an increasingly important cause of septicemia in elderly individuals and immunocompromised patients. Epidemiological studies of GBS infections require comprehensive typing systems that provide information about variable characteristics, such as antigenic type, virulence, or antibiotic resistance, as well as the "backbone" structure or the genetic lineage of isolates. We have previously described a 3-set genotyping system that identifies the molecular serotype (MS) or molecular serosubtype (msst), the protein gene profile, and the presence of several mobile genetic elements (F. Kong, D. Martin, G. James, and G. L. Gilbert, J. Med. Microbiol. 52:337-344, 2003). In this study, 83 clinical GBS isolates which had been previously studied by multilocus sequence typing (MLST) (N. Jones, J. F. Bohnsack, S. Takahashi, K. A. Oliver, M. S. Chan, F. Kunst, P. Glaser, C. Rusniok, D. W. Crook, R. M. Harding, N. Bisharat, and B. G. Spratt, J. Clin. Microbiol. 41:2530-2536, 2003) were examined by using the 3-set genotyping system. Genotypes were assigned to five isolates that were nontypeable by conventional serotyping. There were 27 "3-set" genotypes, 24 multilocus sequence types (STs), and 35 unique combinations (or strains), of which the 4 most common, msst III-2 (ST-17), msst III-1 (ST-19), Ia-1 (ST-23), and V-1 (ST-1), accounted for more than 60% of isolates. The 83 isolates were grouped into seven clusters, with a good correlation between the multilocus STs and the genotypes. The combination of 3-set genotyping and MLST adds discriminatory power to strain typing of GBS, which will be useful for future studies of the epidemiology and pathogenesis of GBS disease.

Bacterial Proteins↗

PubMed1977

Streptococcus group B: an old bug with new dangers.

Infection of the newborn infant with Group B hemolytic streptococcus is increasing in importance as other pathogens decline. Such infection may appear within the first 48 hours of life and resemble respiratory distress syndrome, or around the tenth day, when signs of meningeal irritation may be present. Early onset disease may be due to any of the five serotypes of the Group B streptococcus and is fatal in a high percentage of cases. Late onset infection usually is due to serotype III. The epidemiologic aspects of early and late infection appear to differ, and a nosocomial source may be involved in the latter. Penicillin prophylaxis may be useful.

Humans↗

PubMed2000

Trovafloxacin treatment of viridans group Streptococcus experimental endocarditis.

The activity of trovafloxacin was compared with those of vancomycin and penicillin in a model of Streptococcus sanguis species group (trovafloxacin MIC, 0.125 microg/ml) and Streptococcus mitis species group (trovafloxacin MIC, 0.125 microg/ml) experimental endocarditis. Rabbits with catheter-induced aortic valve vegetations were given no treatment, trovafloxacin at 15 mg/kg of body weight three times a day (t.i.d.), vancomycin at 15 mg/kg twice a day, or penicillin at 1. 2 x 10(6) IU t.i.d. After 3 days of treatment, the animals were sacrificed; cardiac valve vegetations were aseptically removed and cultured quantitatively. Penicillin was as active as vancomycin as measured by in vivo clearance of bacteria. Trovafloxacin was less active (P < 0.05) than vancomycin or penicillin against S. sanguis species group infection but had similar efficacy against S. mitis species group infection. Quinolones, despite MICs in the susceptible range, may not be active for serious infections caused by some viridans group streptococci.

Animals↗

PubMed1984

A case study of Streptococcus group G infection in a dairy herd.

In this paper an outbreak of bovine mastitis in a dairy herd caused by Streptococcus group G is described. Initial identification of the organism as Streptococcus agalactiae was based upon hemolysis, esculin reaction, and CAMP reaction observed on blood agar used for bulk milk analysis. Initial therapy with a penicillin-containing, lactating cow product cured 24.4% of all streptococcal infections. Definitive serogrouping by coagglutination determined that the majority of infections were due to a weakly-hemolytic, esculin-negative Streptococcus group G. Treatment with a cephalosporin, lactating cow product was only moderately successful (54.9%). Dry-cow therapy with 300 mg cephalosporin eliminated 69.5% of refractory infections. Animals remaining infected following dry-cow therapy were culled. Histopathological study of parenchymal tissue in the lower portion of infected quarters revealed mild damage and slight involutionary changes, whereas, deep parenchymal areas appeared relatively unaffected.

Animals↗

PubMed1985

Streptococcus group G septic polyarthritis.

A case of streptococcus group G polyarthritis has been identified from blood and synovial fluid cultures and was sensitive to penicillin G. The clinical tendency to polyarticular infection by this organism and its discordant response to the antibiotics indicated by in vitro studies are discussed.

Arthritis, Infectious↗

PubMed1995

Conformational analysis of oligosaccharides corresponding to the cell-wall polysaccharide of the Streptococcus group A by Metropolis Monte Carlo simulations.

Metropolis Monte Carlo simulations have been performed on four substructures from the cell-wall polysaccharide antigen of Streptococcus group A to explore the conformational behaviour of these compounds. The compounds examined are the trisaccharide, propyl 3-O-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-2-O-(alpha-L-rhamnopyranosyl)- alpha-L-rhamnopyranoside, 1, the tetrasaccharide, propyl 3-O-(3-O-(2-acetamido-2-deoxy-beta-D- glucopyranosyl)-2-O-(alpha-L-rhamnopyranosyl)-alpha-L-rhamnopyranosyl)-alpha-L- rhamnopyranoside, 2, the hexasaccharide, propyl 3-O-(2-O-(3-O-(3-O-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-alpha-L- rhamnopyranosyl)-alpha-L-rhamnopyranosyl)-3-O-(2-acetamido-2-deoxy-beta-D- glucopyranosyl)-alpha-L-rhamnopyranosyl)-alpha-L-rhamnopyranoside, 3, and the hexasaccharide, propyl 3-O-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-2-O-(3-O-(3-O-(2-acetamido-2- deoxy-beta-D-glucopyranosyl)-2-O-(alpha-L-rhamnopyranosyl)-alpha-L- rhamnopyranosyl)-alpha-L-rhamnopyranosyl)-alpha-L-rhamnopyranoside, 4. In general, the conformational flexibility of similar glycosidic linkages in different compounds is comparable. However, in a few cases, small differences in the conformations available to these linkages in different structural environments could be detected. Interestingly, a second conformation found for the beta-D-GlcNAc-(1-->3)-alpha-L-Rha linkage in three of the compounds was not populated in the hexasaccharide 4. Furthermore, a conformational locale of the alpha-L-Rha-(1-->3)-alpha-L-Rha linkage found to be populated in the trisaccharide 1, tetrasaccharide 2, and hexasaccharide 4 is negligibly populated in the hexasaccharide 3. Ensemble averaged proton-proton distances compare favourably with experimental average distances obtained from NMR spectroscopy. The trisaccharide branch point in the hexasaccharides is shown to be a highly defined conformational feature. The same unit has been found to be one of the crucial elements recognized by anti-Group A Streptococcus antibodies, a result that has implications for the design of improved immunodiagnostics and vaccines.

Carbohydrate Conformation↗

PubMed1978

[Autolysis of hemolytic streptococcus group A].

As revealed, autolytic enzymatic system of hemolytic streptococcus, group A, expressed the maximal activity at the end of the exponential growth phase. Autolysis was accompanied by the release of N-acetylaminosugars and of free amino group. Optimal conditions for the lytic system function were chosen (composition, ionic strength, and buffer pH). The activating action of trypsin and chemotrypsin was demonstrated.

Bacteriolysis↗

PubMed1997

Efficacy of azithromycin or clarithromycin for prophylaxis of viridans group streptococcus experimental endocarditis.

The efficacy of azithromycin or clarithromycin was compared to that of amoxicillin, clindamycin, or erythromycin for the prevention of viridans group streptococcus experimental endocarditis. Rabbits with catheter-induced aortic valve vegetations were given no antibiotics or two doses of amoxicillin at 25 mg/kg of body weight, azithromycin at 10 mg/kg, clarithromycin at 10 mg/kg, clindamycin at 40 mg/kg followed by clindamycin at 20 mg/kg, or erythromycin at 10 mg/kg. Antibiotics were administered 0.5 h before and 5.5 h after intravenous infusion of 5 x 10(5) CFU of Streptococcus milleri. Forty-eight hours after bacterial inoculation, the rabbits were killed and aortic valve vegetations were aseptically removed and cultured for bacteria. Infective endocarditis occurred in 88% of untreated animals, 1% of animals receiving amoxicillin, 9% of animals receiving erythromycin, 0% of animals receiving clindamycin, 2.5% of animals receiving clarithromycin, and 1% of animals receiving azithromycin. All five regimens were more effective (P < 0.001) than no prophylaxis. Erythromycin was less effective (P < 0.05) than amoxicillin or clindamycin. Azithromycin or clarithromycin was as effective as amoxicillin, clindamycin, or erythromycin for the prevention of viridans group streptococcus experimental endocarditis in this model.

Amoxicillin↗

PubMed1985

[Determination of antibodies to Streptococcus group A polysaccharide in human sera by an immunoenzyme method].

Use was made of the ELISA to develop a highly sensitive quantitative method for detection of antibodies against Streptococcus group A polysaccharide (polysaccharide A) in human sera. The main advantage is that one can use only one optimal dilution of the sera together with the reference serum. Sera of 53 healthy volunteers and 77 patients with a history of Streptococcus group A infections were screened for the presence of polysaccharide A antibodies. Highly reproducible results were obtained in 97% of cases. The specificity of the method was shown with the polysaccharide A-induced inhibition of the reaction. Positive reactions obtained with the tested sera in gel immunodiffusion correlated with the data derived by the ELISA. Using the latter high level of specific antibodies was found in some of the sera that yielded negative reactions when tested by gel immunodiffusion. This may be associated with the presence of non-precipitating antibodies.

Antibodies, Bacterial↗

PubMed1995

Transferred nuclear Overhauser enhancement experiments show that the monoclonal antibody strep 9 selects a local minimum conformation of a Streptococcus group A trisaccharide-hapten.

Transferred nuclear Overhauser enhancement (TRNOE) experiments have been performed to investigate the bound conformation of the trisaccharide repeating unit of the Streptococcus Group A cell-wall polysaccharide. Thus, the conformations of propyl 3-O-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-2-O-(alpha-L-rhamnopyran osyl)- alpha-L-rhamnopyranoside [C(A')B] (1) as a free ligand and when complexed to the monoclonal antibody Strep 9 were examined. Improved insights about the conformational preferences of the glycosidic linkages of the trisaccharide ligand showed that the free ligand populates various conformations in aqueous solution, thus displaying relatively flexible behavior. The NOE HNAc-H2A', which was not detected in previous work, accounts for a conformation at the beta-(1-->3) linkage with a phi angle of approximately 180 degrees. Observed TRNOEs for the complex are weak, and their analysis was further complicated by spin diffusion. With the use of transferred rotating-frame Overhauser enhancement (TRROE) experiments, the amount of spin diffusion was assessed experimentally, proving that all of the observed long-range TRNOEs arose through spin diffusion. Four interglycosidic distances, derived from the remaining TRNOEs and TRROEs, together with repulsive constraints, derived from the absence of TRROE effects, were used as input parameters in simulated annealing and molecular mechanics calculations to determine the bound conformation of the trisaccharide. Complexation by the antibody results in the selection of one defined conformation of the carbohydrate hapten. This bound conformation, which is a local energy minimum on the energy maps calculated for the trisaccharide ligand, shows only a change from a +gauche to a -gauche orientation at the psi angle of the alpha-(1-->2) linkage when compared to the global minimum conformation. The results infer that the bound conformation of the Streptococcus Group A cell-wall polysaccharide is different from its previously proposed solution structure (Kreis et al., 1995).

Antibodies, Monoclonal↗

PubMed1992

[Significance of normal oral flora, particularly group oral streptococci as defense mechanism against infection in healthy individuals (normal defense mechanism by oral Streptococcus group)].

The alpha-streptococci, consisted of normal oral flora mainly, with inhibitory activity against pathogenic microbes in healthy individuals was investigated by group A Streptococcus (indicator strain 6-22 nonmucoid T-12). Rate of alpha-streptococci with inhibitory activity against group A Streptococcus was increased as aging, and the rate in pre-school children was higher than that in school children. These results suggested that more than 90% of the tested alpha-streptococci with strong inhibitory activities (S. salivarius) against indicator strain had inhibitory activities against group A Streptococcus (mucoid T-6), H. influenzae, S. pneumoniae, group C Streptococcus, and from 40% to 70% of the tested strains had also inhibitory activities against other pathogens. As there were many strains of alpha-streptococci with inhibitory activities against pathogens, that usually detected in the upper respiratory infection, the problem on the strains in the future will explain significance of the defense mechanism against upper respiratory infection and this can be applied clinically.

Adolescent↗

PubMed1998

Structure of the has operon promoter and regulation of hyaluronic acid capsule expression in group A Streptococcus.

Group A streptococcal strains vary widely in the amount of hyaluronic acid capsule they produce, although the has operon, which encodes the enzymes required for hyaluronic acid synthesis, is highly conserved. The three genes making up the has operon are transcribed from a single promoter located upstream of the first gene in the operon, hasA. To investigate transcriptional regulation of capsule synthesis, we studied the structure and function of the has operon promoter sequences from two strains of group A Streptococcus: a highly encapsulated M-type 18 strain and a poorly encapsulated M-type 3 strain. Transcriptional fusions of the has operon promoter to a promoterless chloramphenicol acetyltransferase gene were constructed in a temperature-sensitive shuttle vector. The influence of promoter structure on has operon transcription was reflected by chloramphenicol acetyl transferase activity in cell lysates of Escherichia coli harbouring the recombinant plasmids and in group A Streptococcus after integration of the promoter fusions into the streptococcal chromosome. Fusions including as few as 12 nucleotides upstream from the -35 site of the has promoter exhibited full activity, indicating that sequences further upstream do not affect has gene transcription. A transcriptional fusion of the has promoter from the highly encapsulated M-type 18 strain was threefold more active than a similar construct from the poorly encapsulated M-type 3 strain. Analysis of the promoter sequences for the two strains revealed differences in three nucleotides in the -35, -10 spacer region of the promoter and in four nucleotides in the +2 to +8 positions relative to the start site of hasA transcription. To determine the relative importance of the two groups of nucleotide substitutions, chimeric promoter sequences were constructed in which either of the two clusters of variant nucleotides from the M18 has promoter was substituted for the corresponding positions in the M3 has promoter. Analysis of these chimeric promoter fusions showed that sequence changes in both regions influenced promoter strength. These results define the limits of cis-acting chromosomal sequences that influence transcription of the has operon and indicate that the fine structure of the promoter is an important determinant of capsule gene expression in group A Streptococcus.

Bacterial Capsules↗

PubMed1989

[Streptococcus group B tardive meningitis revealing chronic septic granulomatosis].

A first-born boy operated on D20 for an abscess of the anal margin (E. Coli, Klebsiella) developed purulent meningitis due to a group B serotype III streptococcus on D35. The outcome was rapidly fatal. Results of immunologic investigations done on the day before death were suggestive of chronic granulomatous disease (CGD) as complete absence of reduction of nitroblue tetrazolium (NBT) was evidenced. Studies of polymorphonuclear cells from the mother showed normal production of oxygen, chemiluminescence and NBT reduction. During the subsequent pregnancy, fetal blood was sampled 19 weeks after the last menstrual period; results showed the fetus was male and the polymorphonuclear cells were incapable of reducing NBT and exhibited decreased chemiluminescence and oxygen production. The pregnancy was terminated. This case shows that delayed group B streptococcus infection can occur as the first manifestation of CGD, although this condition is usually responsible for infections due to staphylococci, enterobacteriaceae and yeasts.

Granulomatous Disease, Chronic↗

PubMed1989

[Creation and analysis of a bank of chromosomal genes of Streptococcus group A].

The representative genomic library of chromosomal genes has been constructed for streptococcus group A serotype M48 strain 1/64 on the vector lambda L 47.1. Screening of the obtained genomic library by hybridization and immunological techniques revealed about 50 clones producing the streptococcal antigens (extracellular nonidentified products and non-type specific structural streptococcal proteins). Among the recombinant clones three were found to harbour the genetic determinants for M-protein. One the clones contains a determinant coding for epitopes crossreacting with antisera to M-proteins of other serotypes and a protective epitope. The presence of the latter was tested in an indirect bactericidal test.

Animals↗

PubMed1970

Somatic antigens of Streptococcus group E. II. Separation and a partial physicochemical characterization.

Antigenic extracts of Streptococcus group E (SGE) were subjected to fractional ethanol precipitation, block (preparative) electrophoresis, and gel filtration for the purpose of separating the type antigen from the group antigen. Ethanol precipitation was ineffective in separating the substances. Block electrophoresis yielded serologically pure group antigen and a mixture of type and group antigen. Serologically pure type antigen was obtained by gel filtration. In some cases, pure group antigen was also recovered; in others, it was contaminated with type antigen. Gel filtration column effluents of antigenic extracts of SGE serotypes, I, II, III, IV, V and "untypable" isolates, collected from the region in which type antigen was eluted, were studied by paper chromatography and infrared spectrophotometry in an effort to develop a nonserological means of detecting type antigen. Hydrolysates of type antigens or suspect type antigens of serotypes I through V contained l-rhamnose, d-glucose, and several unidentified substances. d-Galactose also was present in hydrolysates of serotypes III and V. Untypable isolates and negative controls contained traces of d-glucose only. The data suggested that serotypes I through V contained a type antigen and that the untypable isolates were devoid of type antigen. Infrared absorbance spectra seemed to support the paper chromatography data.

Animals↗

PubMed1980

Streptococcus group B isolates in a regional hospital area.

A survey of the frequency of group B streptococcal infections in the Sharon area (Israel) was done in this laboratory. In the female genital tract streptococcus group B was found in 11.8%. This microorganism was recovered in lower frequencies (1.6%-7.4%) in other infection sites (CSF, wounds, throat, blood, and urine). The streptococci were identified as belonging to group B by biochemical properties such as resistance to bacitracin and capability to hydrolyze hippurate. Later the isolates were classified serologically. Serotypes Ib, Ic, and II were predominant in the vaginal smears (25%-28% each serotype). In the other infection sites serotype Ib was the most frequent (36%). The isolates were sensitive to penicillin, cloxacillin, cephalothin, and erythromycin - M.I.C. 0.1-0.2 microgram/ml. Most of the isolates were resistant to tetracycline (69%) and some to chloramphenicol (17.5%). Synergism has been obtained in vitro using a combination of gentamicin and penicillin simultaneously. Group B streptococci or Streptococcus agalactiae first became known because of association with bovine mastitis. This microorganism is now widely appreciated as a potent human pathogen. In several geographic regions it is the leading cause of meningitis during the first two months of life (Eickhoff et al. 1965; Franciosi et al. 1973; Baker et al. 1973; Patterson and Hafeez 1976; Anthony and Okada 1977; Baker 1977). Two clinical syndromes have been defined among infants. The first syndrome, called early onset, is observed in neonates aged five days or less (Baker et al. 1973). In older infants (between 10 days and three months of age) the second syndrome or the late-onset may appear (Franciosi et al. 1973; Baker et al. 1973). In the last few years infections in adults have also been reviewed (Bayer et al. 1976; Lerner et al. 1977). Group B streptococci are divided into five serological types: Ia, Ib, Ic, II, and III (Wilkinson and Eagon 1971); some strains to be devoid of type-specific antigens and are called nontypable (NT). The serotypes of group B streptococci isolated from infants with early onset disease are identical with those isolated from the genital tracts of their mothers. Infants probably acquire the microorganism during passage through the birth canal (Baker and Barrett 1973). Furthermore, the genitourinary tract is known to be a major reservoir of infection and a source for subsequent dissemination in both men and women (Wilkinson 1978). The appearance of sepsis and meningitis in neonates caused by group B streptococci and which was reported previously by this laboratory (Maayan et al. 1978; Nitzan et al. 1978) has prompted us to study the current situation of the infections caused by this microorganism. This study presents a survey on the frequency of infections, serotype distribution, and susceptibility to antimicrobial agents of group B streptococcal isolates in the Sharon district (Israel). It seems that the transformation of the group B streptococci to human pathogens has also affected this area.

Anti-Bacterial Agents↗