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PubMed2006

Streptococcus massiliensis sp. nov., isolated from a patient blood culture.

An unidentified strain of the viridans group of streptococci was isolated from a human blood sample. It was distinguished from all other recognized species of the Streptococcus sanguinis group by several biochemical characteristics. Phylogenetic analysis based on 16S rRNA gene sequence comparisons clustered this strain with Streptococcus ferus (mutans group) but phylogenetic analysis based on rpoB and sodA gene sequence comparisons included it in the S. sanguinis group. The isolate showed 95.4 and 95.2 % 16S rRNA gene sequence similarity to S. ferus and S. sanguinis, respectively, confirming it as belonging to a novel taxon, for which the name Streptococcus massiliensis sp. nov. is proposed. The type strain is 4401825T (=CIP 108498T=CCUG 49690T).

Bacterial Proteins↗
PubMed1991

[A case of remarkable effect of clindamycin in nasal septum abscess caused by Streptococcus milleri].

We encountered a 14-year-old male patient with a destructive abscess of nasal septum, caused by Streptococcus milleri. He was successfully treated with Clindamycin in combination with surgical intervention. We emphasized the significance of Streptococcus milleri as a causative agent for abscess formation, and clindamycin should be considered as a first choice of antibiotics against Streptococcus milleri infection.

Abscess↗
PubMed1982

Conjugative transfer of R-plasmids from Streptococcus faecalis to Staphylococcus aureus.

R-plasmids originally isolated from Streptococcus pyogenes(pAC1,pAM15346), Streptococcus agalactiae(pIP501), and Streptococcus faecalis(pAM beta 1) were shown to be self-transferable on filter membranes from S. faecalis JH2-2 to Staphylococcus aureus recipients. The nonconjugative plasmid pAM alpha 1 was mobilized into S. aureus by pAM beta 1. Once in S. aureus, conjugative R-plasmids could be transferred to a second S. aureus recipient or back into S. faecalis. Determinants for chloramphenicol, clindamycin, erythromycin, and tetracycline resistances present on these streptococcal plasmids were expressed in S. aureus. Agarose gel electrophoresis, dye-buoyant centrifugation, and restriction endonuclease digestion showed that the plasmids were maintained intact as self-replicating elements in S. aureus recipients.

Anti-Bacterial Agents↗
PubMed1984

Selection of Galactose-Fermenting Streptococcus thermophilus in Lactose-Limited Chemostat Cultures.

Stock cultures of Streptococcus thermophilus are essentially galactose negative (Gal). Although both galactose 1-phosphate uridyl transferase and uridine-5-diphospho-glucose 4-epimerase are present, suggesting that the genes for the Leloir pathway exist, cells cannot induce high levels of galactokinase. Therefore, galactose is largely excreted when cultures are grown on lactose, and most strains cannot be readily adapted to grow on free galactose. Gal cultures were grown in a chemostat under lactose limitation in which high concentrations of residual galactose were present. Under this selection pressure, Gal organisms eventually took over the culture with all four strains examined. Gal cells had induced galactokinase, and three of the four strains grew on free galactose with doubling times of 40 to 50 min. When Gal organisms were grown on lactose in batch culture, the galactose moiety was only partially utilized while lactose was still present. As lactose was exhausted, and catabolite repression was lifted, the Leloir pathway enzymes (especially galactokinase) were induced and the residual galactose fermented. Neither phospho-beta-galactosidase activity nor the enzymes of the d-tagatose 6-phosphate pathway were detected in S. thermophilus. In contrast to Streptococcus cremoris and Streptococcus lactis, fermentation was homolactic with galactose in batch cultures and with lactose limitation in the chemostat. When mixed Gal-Gal cultures were repeatedly transferred in milk, the Gal cells became the dominant cell type. The Gal phenotype of stock cultures probably reflects their prolonged maintenance in milk.

Journal Article↗
PubMed1987

Development of High-Frequency Delivery System for Transposon Tn919 in Lactic Streptococci: Random Insertion in Streptococcus lactis subsp. diacetylactis 18-16.

The conjugative transposon Tn919, originally isolated in Streptococcus sanguis FC1, is capable of low-frequency transfer (10 and 10 per recipient) on membrane filters to a wide number of streptococcal recipients including the industrially important lactic streptococci. The introduction of pMG600 (Lac Lax; a lactose plasmid capable of conjugative transfer at high frequencies and which, in certain hosts, confers an unusual clumping phenotype) into a Streptococcus lactis CH919 donor, generating S. lactis CH001, resulted in a significant improvement in the transfer frequency of Tn919 to S. lactis CK50 (1.25 x 10 per recipient). In addition, these matings could be performed on agar surfaces, allowing the recovery of a greater number of recipients than with filter matings. Tn919 also transferred at high frequency to S. lactis subsp. diacetylactis 18-16S but not to Streptococcus cremoris strains. Insertion in 18-16S transconjugants generated from filter matings with an S. lactis CH919 donor was random, occurring at different sites on the chromosome and also in plasmid DNA. Thus, the conditions necessary for the practical exploitation of Tn919 in the targeting and cloning of genes from a member of the lactic streptococci, namely, high-frequency delivery and random insertion in host DNA, were achieved.

Journal Article↗
PubMed1962

STREPTOCOCCAL L-FORMS IV. : Comparison of the Metabolic Rates of a Streptococcus and Derived L-Form.

Panos, Charles (University of Illinois College of Medicine, Chicago, and Albert Einstein Medical Center, Philadelphia, Pa.). Streptococcal L-forms. IV. Comparison of the metabolic rates of a Streptococcus and derived L-form. J. Bacteriol. 84:921-928. 1962.-Glycolytic rates of hexoses, amino sugars, pentoses, two-carbon compounds, and certain intermediates of glycolysis and the adaptive response to glucose of a group A Streptococcus and its derived L-form were compared. It was found that removal of the streptococcal cell wall did not result in the loss of the homolactic characteristic of the parent coccus or in a marked increase in the metabolism of certain glycolytic intermediates by the L-form. It was shown that (i) a major difference exists between the coccus and its L-form in the metabolism of glucosamine and N-acetylglucosamine; (ii) apparently, a loss of selectivity and internal control occurred in the transformation to the L-form; and (iii) this form, unlike the parent coccus, displayed an adaptive response to glucose. These data were not the result of an internal loss of essential cofactors or enzymes by diffusion from within the L-form. Nor could they be accounted for by dry-weight differences due to loss of the streptococcal cell wall. Finally, it was observed that the sonically disintegrated L-form in 0.5 m NaCl was capable of a glycolytic activity of 46% of that of the total intact culture. These data suggest that the conversion of a streptococcus to the L-form is accompanied by an alteration in carbohydrate metabolism as well as the loss of the cell wall. Previously reported data are in agreement with these findings and support the conclusion that the resulting form is not merely a bacterial cell without a rigid cell wall.

Journal Article↗
PubMed1972

Trimethoprim-sulphamethoxazole in urinary tract infection due to Streptococcus faecalis.

In-vitro sensitivities were performed on 140 specimens of urine which grew Streptococcus faecalis of more than 100 000 organisms/ml between March 1970 and February 1971. Although the combination of trimethoprim and sulphamethoxazole definitely appeared to be more effective than sulphonamide alone and as effective as ampicillin, its use for more than two weeks in 14 cases of uncomplicated urinary tract infection due to Streptococcus faecalis led to development of resistance. As in these cases organisms were resistant to sulphonamide to start with, it is suggested that the combination should be used in prolonged treatment only where the organisms are sensitive to both the individual antibiotics. Ampicillin is still the drug of choice in urinary tract infection due to Streptococcus faecalis. The alternative appears to be rotational therapy with other potent antibiotics.

Ampicillin↗
PubMed1986

Characterization and partial purification of a broad spectrum antibiotic AS-48 produced by Streptococcus faecalis.

Streptococcus faecalis S-48 produces a broad spectrum antibiotic, active against Gram-positive and Gram-negative bacteria. This substance is produced in solid and liquid media and also in a defined basal medium. It is sensitive to protease, pronase, or trypsin, heating at 70 degrees C, and alkaline pH, but resistant to treatment with lipase, lysozyme, alkaline phosphatase, DNAase, RNAase, acidic or neutral pHs, and also lower temperatures (60 degrees C). Several organic solvents cause precipitation, but not inactivation. This antibiotic has been partially purified by gel filtration and further ion-exchange chromatography. Its molecular weight has been estimated close to 2000. The biological activity of this antagonistic substance against the selected indicator strains, Streptococcus faecalis S-47 and Escherichia coli U-9, is bactericidal. The characterization of this substance, initially classified as a bacteriocin, indicates that it is an antibiotic of peptidic nature. The significance of antibiotic occurrence in group D of the genus Streptococcus is also discussed.

Anti-Bacterial Agents↗
PubMedDate not supplied

Endogenous group G Streptococcus endophthalmitis following a dental procedure.

PURPOSE: To report a case of bilateral endogenous endophthalmitis due to group G Streptococcus after a dental procedure. METHODS: Case report of a 69-year-old woman who presented with pain, decreased vision, bilateral uveitis, and a unilateral hypopyon 1 week after treatment for an abscessed tooth. RESULTS: Bilateral endophthalmitis was diagnosed, and group G Streptococcus was cultured from the vitreous samples. CONCLUSIONS: To our knowledge, this is the second reported case of endogenous endophthalmitis following a dental procedure. Furthermore, it was due to group G Streptococcus, which is a rare cause of this condition.

Aged↗
PubMedDate not supplied

[Nasopharyngeal colonization and antimicrobial resistance of Streptococcus pneumoniae isolated from children with acute rhinopharyngitis]

OBJECTIVE: To determine the prevalence and risk factors for nasopharyngeal colonization by, and to evaluate antimicrobial susceptibility of Streptococcus pneumoniae strains in children with acute rhinopharyngitis. METHODS: We collected nasopharyngeal swab specimens from 400 children aged 3 months to 5 years and with clinical status of acute rhinopharyngitis from June 16, 1997 to May 20, 1998 at the outpatient clinics of two hospitals in the city of São Paulo. Nasopharyngeal specimens were collected pernasally using a calcium alginate swab and plated immediately after collection onto trypticose soy agar with 5% sheep blood and garamicin 5 mcg/ml. Penicillin susceptibility was determined by oxacillin 1 mcg disk screening test and the minimal inhibitory concentration by the E-test. RESULTS: Pneumococci were recovered from 139 children, indicating a colonization prevalence of 35%. The risk factors analyzed indicated that the colonization was more prevalent in children attending day-care centers, children with siblings younger than 5 years, and children with recent use of antimicrobial agents. The prevalence of penicillin non-susceptible strains was of 16 % (20 strains). All strains were intermediately resistant (0.1mcg/ ml </= MIC </= 1.0 mcg/ ml). Out of the penicillin intermediately resistant strains, 7 (37%) showed intermediate resistance to cotrimoxazol and 2 (11%) full resistance to trimethoprim-sulfamethoxazole. No strains were resistant to ceftriaxone, amoxicillin, clarithromicin, or chloramphenicol. CONCLUSIONS: Our findings indicate that the prevalence of nasopharyngeal colonization by Streptococcus pneumoniae in children with upper respiratory infections was of 34.8%. Children attending day-care centers and children with younger siblings showed higher levels of colonization The results of prevalence of bacterial resistance were similar to those of studies regarding invasive infections, thus indicating that nasopharyngeal isolates of Streptococcus pneumoniae can be used in the surveillance of antimicrobial resistance in a defined geographical area.

Journal Article↗
PubMedDate not supplied

Streptococcus milleri infection and pericardial abscess associated with esophageal carcinoma: report of two cases.

We report 2 cases of esophageal carcinoma with esophago-mediastinal fistula that developed pericardial abscess due to Streptococcus intermedius infection. Streptococcus intermedius, a generally harmless commensals in healthy humans, is not usually associated with infections of the oral cavity but may account for non-oral purulent infections. This report, however, highlights that Streptococcus intermedius infection can be life-threatening for some patients such as those with esophageal carcinoma with fistula.

Abscess↗
PubMed2001

[Reactive arthritis shortly after Streptococcus b-hemolyticus type A and Salmonella type B infection].

We report the case of a girl aged 2 years and 8 months with monoarticular arthritis of the knee. Onset and outcome were slow. The child had suffered uncomplicated pharyngitis and a diarrheal process 1 and 2 weeks respectively prior to developing the disease. Additional data suggested the presence of reactive arthritis after Streptococcus infection. Salmonella was also detected in the feces. Unlike rheumatic fever, post-streptococcus reactive arthritis does not follow Jones' criteria and the clinical course is slow. Because gastrointestinal infection with both Streptococcus and Salmonella occurred simultaneously, the interaction between both agents, each of which alone can cause reactive arthritis, might have produced a synergic action in our patient.

Arthritis, Reactive↗
PubMed2003

Viridans streptococcus bacteremia in children on chemotherapy for cancer: an underestimated problem.

The authors discuss the morbidity associated with viridans streptococcus bacteremia, and its implications on the choice of antibiotics used as prophylaxis and treatment. They retrospectively studied the case notes of 38 children who were being treated for various malignant conditions in their unit and developed 40 episodes of bacteremia with viridans streptococci between October 1995 and January 1999. Viridans streptococci were the third commonest blood culture isolate during this period, after coagulase-negative staphylococci and Staphylococcus aureus. The majority of the isolates were Streptococcus mitis (55%). Others were S. sanguis (25%), S. oralis (12.5%), S. salivarius (5%), and S. acidominimus (2.5%). Twenty-five percent of the patients had been treated with regimens that included cytosine arabinoside, 60% were receiving prophylactic co-trimoxazole, and 87.5% were neutropenic. Thirty percent of patients had abnormal chest X-rays, and 15% were hypotensive; 2 patients required admission to the intensive care unit. Initial antibiotic therapy was changed because of failure of clinical response in 60% of cases, despite the infecting organism being sensitive in vitro. This study confirms the importance of viridans streptococci as a cause of bacteremia in pediatric hematology and oncology patients, leading to significant morbidity. Further work is required to establish the optimal treatment for viridans streptococcus bacteremia.

Adolescent↗
PubMed2003

Infective endocarditis caused by group G streptococcus with multiple cerebral emboli.

The group G streptococcal endocarditis is a rare form of infective endocarditis. In this form of infective endocarditis, serious neurological complications most commonly develop. We reported this case because of its being an unusual form of infective endocarditis that was caused by Group G Streptococcus. We also reviewed the literature. The patient was admitted to infectious disease service with a presumptive diagnosis of central nervous system infection. Blood cultures were positive for group G streptococcus. There was a mass on the posterior surface of the mitral valve which was 2 x 2.5 cm in length on the echocardiography. In the cranial computerized tomography of our patient, slightly increased contrast media uptake was observed in the both parietal lobes, in the both frontal lobes, and in the anterior areas of right occipital lobe. Therefore, this case was assumed as infective endocarditis caused by group G streptococcus with multiple cerebral emboli. Ceftriaxone was given for 4 weeks and gentamicin was given for 2 weeks, and progressive improvement of the patient's condition was seen.

Adult↗
PubMed1996

[Epidemiologic surveillance of streptococcus pyogenes resistances to macrolides and lincosamides].

With the changing face of modern medicine and increased use of new antimicrobial compounds against Streptococcus pyogenes, as macrolides, in recent years more strains developed new resistance to macrolides and lincosamides. This is of interest because some scientists believe that the new antibiotics policies possibly influence the rate of resistance in Streptococcus pyogenes: the pattern of resistance to macrolides is complex and involving cross or co-resistance with chemically unrelated or related agents, as lincosamides. To obtain current epidemiological data on antimicrobial resistance of Streptococcus pyogenes, we performed an year surveillance study: the rate of resistance to erythromycin was from 4% in October 1994 to 55% in December 1995, and in the same time clarithromycin was from 0% to 46% and clindamycin from 0% to 32%.

English Abstract↗
PubMed2000

[In vitro study of Streptococcus mutans in the plaque on the surface of amalgam fillings on the conversion of inorganic mercury to organic mercury].

OBJECTIVE: To study the Streptococcus mutans in the plaque on the surface of amalgam fillings on the conversion of inorganic mercury to organic mercury. METHODS: Plaque was sampled from the amalgam restorations after amalgam filling regularly, serving the unfilled tooth as control. Streptococcus mutans was identified and inoculated to 10 ml TSB. After incubated 24 hours, mercury in water was added to the concentration of 100 ng/ml, incubated 24 hours again, the concentration of inorganic and organic mercury was determined. RESULTS: It was found that the difference of organic mercury and organic mercury between the baseline and the times after amalgam filling in test group and control was significant, while the difference between the times after amalgam filling was not significant, and the difference between the test group and the control was not significant, either. CONCLUSION: Streptococcus mutans can convert inorganic mercury to organic mercury in some way, and the mercury of amalgam plays some role in it.

English Abstract↗
PubMed2005

[Severe Streptococcus agalactiae infection of the diabetic foot.]

A DELETERIOUS ROLE OF STREPTOCOCCUS AGALACTIAE?: Introduction Screening strategies among pregnant women have decreased the incidence of group B Streptococcus, which causes severe neonatal infections. The incidence of these infections has increased among diabetic patients, however. OBJECTIVES: To specify the characteristics of diabetic foot infections in which surgical samples have isolated one or several germs including group B Streptococcus, study its risk factors and determine its course. Materials and methods We retrospectively evaluated the records of all patients admitted to the University Hospital of Geneva from January 1999 through October 2004, with diagnoses of severe foot infection (+/- osteomyelitis) documented during surgery. RESULTS: Twenty-five severe diabetic foot infections were identified, 21 with osteomyelitis. The most common risk factors were age older than 60 years (n=10), chronic renal failure (n=7), severe arteriopathy (n=6), and immune depression (n=2). Most lesions were classified as grade 3 or 4 of Wagner's classification. 80% of the surgical samples were polymicrobial. Blood cultures were positive in 4 patients, one in septic shock. Half the patients (n=13) underwent amputation, despite initially appropriate antibiotic treatment. No patients died but 3 relapsed. CONCLUSION: Group B streptococcal foot infections often occur in fragile patients with immune depression or severe arterial disease. Despite intensive antibiotic therapy and adequate debridement, amputation is often required in diabetic patients because of severe damage to the tissue and poor vascularization.

Journal Article↗
PubMed1991

Group G streptococcus septic arthritis and osteomyelitis: report and literature review.

Beta hemolytic streptococcus group G is increasingly being recognized as a cause of serious infections. We describe a patient with group G streptococcus septic arthritis of the right knee and osteomyelitis of the proximal tibia. Clinical details of 46 patients including 13 patients with infected prosthetic joints reported in the literature were reviewed: 42% had multiple joint involvement. Almost all patients had underlying conditions. Almost one-half were treated with antibiotics alone without therapeutic drainage procedures. Patients with infected prosthetic joints did well without removal of infected prosthesis. There have been 11 cases of group G streptococcus osteomyelitis reported including 3 cases with concomitant septic arthritis.

Arthritis, Infectious↗