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PubMed1994

[Invasive Streptococcus pyogenes infection (beta-hemolytic Streptococcus of group A)].

Group A streptococcal infections are frequent and most often benign. Severe invasive infections due to this microorganism have nevertheless been reported with increasing frequency in various countries for several years. Moreover, a toxic shock-like syndrome has recently been recognized and characterized in such infections. Two cases of invasive group A streptococcal infections (one primary peritonitis and one toxic shock syndrome) are reported to increase a better understanding of this disease in the light of a review of the pertinent literature. This is hoped to contribute to better management of what is a growing problem for many physicians who are nowadays no longer familiar with the broad spectrum of group A streptococcal infections.

Abdomen, Acute↗
PubMed1975

Streptococcus faecalis and Streptococcus faecium in infected dental root canals at filling and their susceptibility to azidocillin and some comparable antibiotics.

The study was performed on 612 routine cultures of material obtained from root canals of teeth at the time of filling (r-cultures) by students at the Department of Endodontics during a continuous period of one year. Twenty-nine isolates from 27 (29.3%) of the 92 positive cultures filled the criteria of enterococci (Sherman, 1937) and had demonstrable group D-antigen. With a set of tests these isolates were identified as follows: Strep. faecalis subsp. faecalis (10), Strep. faecalis subsp. zymogenes (3), Strep. faecalis subsp. liquefaciens (8), atypical variants of Strep. faecalis (6), Strep. faecium var. faecium (1) and Strep. faecium var. durans (1). Five tests in the present study clearly differentiated Strep. faecalis from Strep. faecium i.e. fermentation of sorbitol, glycerol (anaerobic) and melezitose, tolerance to potassium tellurite (0.1%) (positive for Strep. faecalis) and production of hydrogen peroxide (positive for Strep. faecium). In the inocula 10(3) or more colony forming units of enterococci were found more often of other identified microorganisms. This means that enterococci are of special interest in studies on the influence of infection at the time of filling of root canals on the prognosis of root canal therapy. The isolates were also tested for susceptibility to azidocillin, ampicillin, penicillin-G, penicillin-V and erythromycin with the paper disc method. All the isolates were susceptible to azidocillin and ampicillin (sensitivity group I), while the majority of the isolates showed a lower susceptibility to the other three antibiotics (sensitivity group II). The significance of these findings in the choice of prophylactic antibiotic to prevent bacterial endocarditis in patients with a history of rheumatic or congenital heart disease are discussed, when bacteremia from dental procedures may be expected.

Ampicillin↗
PubMed1997

Effectiveness of ribosomal fractions of Klebsiella pneumoniae, Streptococcus pneumoniae, Streptococcus pyogenes, Haemophilus influenzae and the membrane fraction of Kp (Ribomunyl) in the prevention of clinical recurrences of infectious rhinitis. Results of a multicenter double-blind placebo-controlled study.

A multicenter, double-blind, placebo-controlled study was conducted to investigate the efficacy of an immunostimulant, Ribomunyl, in the prevention of recurrences of infectious rhinitis in adults. This trial involved 327 patients (168 Ribomunyl treated and 159 placebo cases) with an average of 4.3 +/- 1.8 rhinitis episodes per patient recorded during the year preceding the study. The main criterion of efficacy was the cumulative number of recurrences of infectious rhinitis during a 6-month follow-up period, as analyzed by standard tests. An additional analysis of relative risk of recurrences used multivariate failure for time data. Ribomunyl was effective throughout the study period, starting from the first month of treatment: a mean of 1.0 +/- 1.1 recurrences was recorded in the Ribomunyl group as compared to 1.5 +/- 1.4 recurrences in the placebo group; this indicated one-third fewer infections (P = 0.001). The protective effect of Ribomunyl on the relative risk for recurrences was estimated to be 0.58 by multivariate analysis (95% CI: 0.43-0.78, P = 0.0001). Analysis of secondary criteria also favored Ribomunyl: 38.5% less antibiotic courses per patient (0.8 +/- 1.3 vs 1.3 +/- 1.6; P = 0.002) and the number of days with antibiotics (5.6 +/- 9.3 vs 9.1 +/- 12.1; P = 0.002).

Adjuvants, Immunologic↗
PubMed1989

A new simple method of curing plasmids in lactic streptococci (Streptococcus cremoris; Streptococcus lactis, plasmids).

A simple method for curing plasmid DNA from lactic streptococci is described. When strains of lactic streptococci are grown overnight at 32 degrees C in an unbuffered medium (M17-) and held at the same temperature for an extended period (96 h), the acid environment induces loss of plasmid DNA of different sizes. If the process of growth in M17- broth followed by extended incubation at 32 degrees C is repeated, most of the plasmids are lost, as revealed by gel electrophoretic profiles of DNA. The method is simple and efficient in curing plasmids of lactic streptococci without use of any mutagenic chemical.

Culture Media↗
PubMed2001

[Base composition of DNA from fluoride resistant strains of streptococcus mutans and streptococcus sobrinus].

OBJECTIVES: To evaluate the genotype change of fluoride-resistant strains of S.mutans and S.sobrinus. METHODS: High potential liquid chromatography was used to measure the base composition of DNA from F-resistant strains of S.mutans and S.sobrinus and their parent strains. RESULTS: The data showed that the DNA G+C mol% of F-resistant and F-sensitive S.mutans were quite different, the difference was over 5%. The four F-resistant strains were 54.45, 44.86, 54.41, 55, 390, whereas the corresponding four parent strains were 35.38, 37.4, 43.35, 46.62, respectively. CONCLUSION: The genotypes of F-resistant strains of S.mutans and S.sobrinus have been changed and may comprise several gene mutations.

English Abstract↗
PubMed1996

[A comparative analysis of biological properties of glucosylrtanterases secreted by Streptococcus sanguis and Streptococcus mutans]

Our study make a comparative analysis of biological properties of glucosyltranterases(GTF) secreted by S.sanguis 34 and S.mutans Ingbritt(c).The results as follows:(1)S.sanguis 34 has more extractions of extracelluar GTF than S.mutans Ingbritt(c) under equal cultured conditions,but S.mutans Inggbritt(c) has more activity of extracelluar GTF than S.sanguis.These differences are identical with the difference of their cariogenicities;(2)GTF of S.sanguis 34 can also synthesize water-soluble glucan,and is a multienzyme complex system as S.mutans. S.sanguis might catalyse sufficient dextran formation to stimulate the primer-dependent activity of the S.mutans GTF enzyme. This might aid the adhesion of this comparatively late colonizer;(3)easier to obstruct high pure GTF of S.sangusi 34 S.mutans.

Journal Article↗
PubMed1996

[Environmental factors in oral cavity effect on growing of Streptococcus sanguis and Streptococcus mutans-effect of Mucin]

Our study use continues culture technique through adding mucin as the limiting element in chemically defined culture,medium in order to observe growing states of S.sanguis 34 and,S.mutants Ingbritt(c).The results as follows:S.sanguis 34 were able to grow as pure culture on mucin;S.mutans was unable to grow as a pure culture on mucin,but attained a significant population size in the presence of S.sanguis.These results indicate a synergetic degradation of mucin by S.sanguis and S.mutans in mixed chemism culture.

Journal Article↗
PubMed2002

Streptolysin S and necrotising infections produced by group G streptococcus.

BACKGROUND: We encountered three patients with severe necrotising soft tissue infections due to beta-haemolytic group G streptococcus. Due to strong clinical similarities with invasive infections produced by group A streptococcus, we investigated a potential link of shared beta-haemolytic phenotype to disease pathogenesis. METHODS: Hybridisation, DNA sequencing, targeted mutagenesis, and complementation studies were used to establish the genetic basis for group G streptococcus beta-haemolytic activity. The requirement of group G streptococcus beta-haemolysin in producing necrotising infection was examined in mice. FINDINGS: Each patient had an underlying medical condition. beta-haemolytic group G streptococcus was the sole microbial isolate from debrided necrotic tissue. The group G streptococcus chromosome contained a homologue of the nine-gene group A streptococcus sag operon encoding the beta-haemolysin streptolysin S (SLS). Targeted mutagenesis of the putative SLS structural gene sagA in group G streptococcus eliminated beta-haemolytic activity. Mice injected subcutaneously with wild-type group A streptococcus or group G streptococcus developed an inflammatory lesion with high bacterial counts, marked neutrophil infiltration, and histopathological evidence of diffuse tissue necrosis. These changes were not found in mice injected with the isogenic group A streptococcus or group G streptococcus SLS-negative mutants. INTERPRETATION: In patients with underlying medical conditions, beta-haemolytic group G streptococcus can produce necrotising soft tissue infections resembling those produced by group A streptococcus. The beta-haemolytic phenotype of group G streptococcus is produced by the exotoxin SLS, encoded by a functional homologue of the nine-gene group A streptococcus sag operon. SLS expression contributes to the pathogenesis of streptococcal necrotising soft tissue infection.

Animals↗
PubMed2005

[Clinical, echocardiographic and prognostic profile of Streptococcus viridans left-sided endocarditis].

INTRODUCTION AND OBJECTIVES: Published case series on Streptococcus viridans endocarditis are scarce and outdated. The aims of our study were multiple: to analyze the profile of the Streptococcus viridans endocarditis, to compare it with other types of left-sided endocarditis and with cases caused by Staphylococcus aureus, and to determine predictors of poor outcome in Streptococcus viridans endocarditis. PATIENTS AND METHOD: We analyzed 441 episodes of endocarditis: 330 left-sided and 54 caused by Streptococcus viridans (16%). We compared the 54 cases due to Streptococcus viridans with the remaining cases of left-sided endocarditis in our series, and also with cases caused by Staphylococcus aureus. We also analyzed the predictors of death and urgent surgery in Streptococcus viridans endocarditis. RESULTS: Left-sided endocarditis due to Streptococcus viridans led to a similar degree of valvular destruction, showed acute onset less frequently, and led to less renal failure, septic shock and mortality than the remaining cases of left-sided endocarditis in our series. The same differences were found in comparison to Streptococcus viridans endocarditis. Prognostic factors for Streptococcus viridans left-sided endocarditis were heart failure and periannular complications. CONCLUSIONS: Although Streptococcus viridans is a nonaggressive microorganism, valvular destruction is similar to that caused by other pathogens when it causes left-sided endocarditis. Nonetheless its prognosis is better, a feature which may be related to the fact that the systemic infectious syndrome can be treated more effectively. Prognostic factors in left-sided endocarditis due to Streptococcus viridans are heart failure and periannular complications.

Aortic Valve↗
PubMed2005

No increase in rates of early-onset neonatal sepsis by antibiotic-resistant group B Streptococcus in the era of intrapartum antibiotic prophylaxis.

OBJECTIVE: The aim of this study was to assess the rate of early-onset neonatal sepsis by antibiotic-resistant group B Streptococcus. STUDY DESIGN: The time-trend study was conducted at a tertiary care center over the following periods: no protocol for group B Streptococcus prophylaxis (1990 to 1992), risk-based protocol (1993 to 1996), and screening-based protocol (1997 to 2002). RESULTS: A total of 120,952 neonates were born with 118 cases of group B Streptococcus early-onset neonatal sepsis. The rate of group B Streptococcus early-onset neonatal sepsis decreased significantly (from 2.0 to 1.1 to 0.4 per 1000 births, P < .0001). No group B Streptococcus isolate was resistant to ampicillin, penicillin, cefazolin, or vancomycin. From 1997 to 2002, there were 3 clindamycin-resistant group B Streptococcus isolates (14%). The rate of erythromycin-resistant group B Streptococcus early-onset neonatal sepsis did not change (from 0.14 to 0.03 to 0.08 per 1000 births, P = .6). However, cases of erythromycin-resistant group B Streptococcus early-onset neonatal sepsis accounted for an increasing proportion of the remaining cases of group B Streptococcus early-onset neonatal sepsis (from 7.0% to 2.6% to 23.8%, P = .07). CONCLUSION: We found no increase in rates of antibiotic-resistant group B Streptococcus early-onset neonatal sepsis.

Age of Onset↗