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[Streptococcus salivarius meningitis after spinal anesthesia].

Streptococcus salivarius is a usual commensal of skin, gastrointestinal tract, genitourinary tract, oral cavity and paranasal sinuses. Although it is usually considered to have low virulence, S. salivarius may cause life-threatening infections, particularly endocarditis. On the other hand, bacterial meningitis after spinal anesthesia is very rare, there being some reported cases caused by S. salivarius, S. mitis, Staphylococcus aureus and Enterococcus faecalis. We report a 57 year old man who developed meningitis symptoms within 10 h of an uncomplicated inguinal herniorrhaphy performed during spinal anesthesia. Cerebrospinal cultures grew S. salivarius sensitive to penicillin. The patient was successfully treated with penicillin G and left the hospital without sequelae. In the literature, bacterial meningitis due to S. salivarius is rarely reported. Of the 28 cases, 18 occurred after lumbar puncture for diagnostic or for spinal anesthesia, 5 occurred following a bacteriemia for upper gastrointestinal endoscopy or intestinal neoplasia, and the other 5 in patients who had dural defects. We discuss the possible etiological causes of the meningitis due to S. salivarius cases reports. The early recognition of this entity and the aseptic precautions likely to reduce the incidence of infectious complications after lumbar puncture are stressed.

Anesthesia, Spinal↗

PubMed1994

[Clinical significance of bacteremia caused by streptococci of the viridans group].

BACKGROUND: The viridans group Streptococcus (SVG) include species which may have different pathogenic capacity. This study was aimed at evaluating the clinical significance of bacteremia by different species of SVG. PATIENTS AND METHODS: One hundred ninety-four clinical records of patients with blood culture(s) isolation (Hémoline/BioMérieux) of SVG (Api 20 STREP/BioMérieux) over 9 years were reviewed with criteria of clinical significance being established and the results analyzed by the chi square test. RESULTS: The most frequent species of SVG isolated were: S. sanguis II (29.4%), S. mitis (27.3%) and S. anginosus (12.9%). With regard to the criteria established, 36% of the isolates were clinically significant, associating S. anginosus with significant bacteremia (p = 0.001) and S. mitis with non significant bacteremia (p = 0.04). More than half of the isolations of S. anginosus, S. bovis, S. mutans and S. adjacens were clinically significant with this rate being lower in the remaining species (S. sanguis I, S. sanguis II, S. mitis, S. salivarius and S. acidominimus). The significant isolations correspond with endocarditis (S. sanguis II being responsible for 44%; p = 0.05). In 54.3% of the cases followed by abscesses or other localized infections and severe sepsis in patients with a solid or hematologic tumor with a mortality of 20%. The endocarditis/other disease relation was: greater for the existence of endocarditis for S. sanguis II, S. sanguis I, S. mutans, S. bovis and S. adjacens; similar in both diseases for S. mitis, and greater for the existence of a non endocardic disease for S. anginosus. CONCLUSIONS: In this series the isolation of SVG group was clinically significant in 36% of cases with a probability of clinical significance and disease association related to the species isolated of SVG.

Adolescent↗

PubMed1983

Numerical taxonomy of Streptococcus.

A numerical taxonomic study of strains of Streptococcus, together with representatives of allied genera, showed 28 reasonably distinct phenons. The major areas, with their phenons, were: (a) enterococcal species group (S. faecalis, S. faecium, 'S. avium' and a proposed new species 'S. gallinarum'); (b) paraviridans species group (S. bovis, S. equinus, S. salivarius, 'S. casseliflavus', S. mutans, S. raffinolactis and an unidentified Oral Group I); (c) lactic species group (S. lactis including S. cremoris); (d) thermophilic species group (S. thermophilus); (e) viridans species group (S. mitis, S. sanguis, a proposed new species 'S. oralis' and 'S. milleri'); (f) pyogenic species group (S. agalactiae, S. pyogenes, S. equi, 'S. equisimilis' including 'S. zooepidemicus, and a cluster of Lancefield Group B strains of human origin); (g) parapyogenic species group (S. uberis, 'S. dysgalactiae', and a cluster of strains of Lancefield Groups R, S and T). Species of Aerococcus, Gemella, Leuconostoc and Pediococcus are very closely related to the streptococci.

Enterococcus faecalis↗

PubMed1976

Correlation between streptococci of human dental plaques and dental caries.

Plaque samples from 27 buccal tooth surfaces were obtained with sterile McCall curettes from available third molars. Bacteriological sampling and biochemical tests were carried out to identify four groups of streptococci, i.e. Str. mutans, Str. spp., Str. sanguis and Str. mitis. Clinical examinations carried out 6 months after the dental scrapings were taken showed a strong positive correlation between detectable lesions and Str. mutans.

Dental Caries↗

PubMed1981

Isolation and characterization of Streptococcus mutans mutants defective in adherence and aggregation.

A method was developed which enriched for mutants of Streptococcus mutans that exhibit defects in adherence to glass, aggregation, or both. Mutants were isolated from derivatives of strains PS14 (serotype c) and 6715 (serotype g) after mutagenesis with either ethyl methane sulfonate or nitrous acid. Cell survival after mutagenesis was kept above 1 to 2% to enhance the probability that mutants resulted from single mutational events. A total of 117 mutants were isolated; they also displayed non-wild-type colony morphology on mitis salivarius agar. These mutants were examined for (i) adherence and aggregation after overnight growth in sucrose-containing medium, (ii) aggregation of nongrowing cells in the presence of 200 microgram of sucrose per ml or 20 microgram of dextran per ml, and (iii) dextranase production on blue dextran agar plates. Although we isolated mutants which exhibited a variation from the parent strain in only one of the traits tested, the majority of mutants exhibited defects in two or more characteristics. Thirty-eight stable mutants of independent origin were categorized into 13 separate phenotypic groups.

Cell Adhesion↗

PubMed1996

Penicillin-binding proteins as resistance determinants in clinical isolates of Streptococcus pneumoniae.

Altered penicillin-binding proteins (PBPs) with reduced affinity for penicillin are encoded by mosaic genes in penicillin-resistant clinical isolates of Streptococcus pneumoniae. Generally, members of one bacterial clone contain the same mosaic gene. We report here on a serotype 19A clone of penicillin- and multiple-resistant S. pneumoniae prevalent in Hungary, members of which are exceptionally diverse in terms of PBP properties. The pbp2x gene of four 19A isolates was sequenced, and a distinct mosaic structure detected in each case. The pbp2x genes also differed from a homologous gene of a high-level penicillin-resistant S. mitis from Hungary. The contribution of PBPs to resistance development was studied on transformation experiments using the laboratory strain R6 as recipient, and PBP genes from the type 19A isolate Hu11. pbp2x and pbp2b function as primary resistance determinants for different beta-lactams. Secondary transformation with pbp1a increased the resistance level considerably for penicillins and cefotaxime. Chromosomal DNA of a high-level penicillin- and cefotaxime-resistant S. mitis from Hungary also transformed the R6 strain to increased resistance levels, and PBP2x and PBP2b functioned as primary resistance determinants as above. In contrast, high-level cefotaxime resistance appeared to be due to a low affinity PBP2a, indicating that this PBP can also function as a resistance determinant.

Aminoacyltransferases↗

PubMed2002

Comparison of five selective media for the growth and enumeration of Streptococcus mutans.

BACKGROUND: Although a few growth media are available for selective isolation of the cariogenic bacteria, Streptococcus mutans (S. mutans), it is still unclear as to which is the most efficacious. This study compared the selectivity and sensitivity of five different media for growing a laboratory strain of S. mutans (NCTC 10449), and for enumerating S. mutans from teeth of a group of young children, aged 2-10 years. METHODS: The media tested in this study were mitis salivarius with bacitracin (MSB), mitis salivariuskanamycin-bacitracin (MSKB), glucose-sucrose-tellurite-bacitracin (GSTB), trypticase soy-sucrose-bacitracin (TYS20B) and tryptone-yeast-cysteine-sucrose-bacitracin (TYCSB) agars. These were prepared according to the respective manufacturer's instructions. RESULTS: The results showed that at concentrations of bacteria 1 x 10(3) to 1 x 10(10)/mL, the recovery of the laboratory S. mutans strain was highest in TYCSB agar, followed by in descending order by TYS20B, MSB, GSTB, and MSKB (p<0.01). Similar results were obtained using dental plaque samples collected from swabs of the teeth of a group of children. In the clinical samples, TYCSB again showed the highest recovery rates of S. mutans compared to the other four media. Results were reproduced at dilutions of the samples at 1:20 x 10(6) to 1:2 x 10(6), and S. mutans concentrations of 1.6 to 7.7 Log 10 CFU/mL. In addition, there were highest ratios of mutans to non-mutans bacteria in TYCSB compared to the other media, suggesting high selectivity of this media for mutans species. CONCLUSION: The results of our study suggest that TYCSB is the most sensitive and selective media for culture of S. mutans for laboratory and clinical studies.

Agar↗

PubMed1990

Effect of TiF4 solutions on bacterial growth in vitro and on tooth surfaces.

The purpose of this study was to assess the antimicrobial effect of TiF4 as compared with equimolar solutions of NaF, APF, and SnF2 and to evaluate the effect, if any, on bacterial growth on topically treated tooth surfaces. In an in vitro study, paper discs impregnated with 20 microliters of equimolar solutions of SnF2, NaF, APF, and TiF4 were placed on blood agar plates seeded with Streptococcus mutans and Bacteroides gingivalis. Sterile saline was used as control. Similar growth inhibition zones were found for all fluorides. In the second part of the study six volunteers carried intraoral appliances containing enamel and root surface specimens treated with 1% TiF4 and untreated specimens for 18 h. Scanning electron microscopic examination of the experimental tooth surfaces showed great variation in bacterial growth between subjects, but no systematic difference between fluoride-treated and untreated specimens. Bacteria from test and control specimens were grown under aerobic and anaerobic conditions on blood agar and on mitis salivarius agar. Colony-forming unit counts showed great interindividual variations, but no differences could be observed between treated and untreated enamel or root surfaces. Thus, the hypothesis that the presence of a Ti-rich coating may influence bacterial colonization on TiF4-treated tooth surfaces could not be substantiated.

Bacteria↗

PubMed1968

Cores, microbial organelles possibly specific to group D streptococci.

A long, thin, approximately cylindrical core spans the interior of cells of 24-hr cultures of all group D streptococci that were examined, five strains of Streptococcus faecalis, single strains of S. faecalis subsp. zymogenes and S. durans, and three strains of Streptococcus spp. In one strain of S. faecalis, serial section electron microscopy showed that most cells possess a core. The core is 0.10 to 0.16 mum thick and consists of a matrix and an axial array of ribosomelike particles. It resembles one of two types of cores present in a stable protoplast form of one of the S. faecalis strains. Cores were not present in single strains of S. pyogenes (beta-hemolytic group A), S. agalactiae (group B), S. dysgalactiae (group C), S. equisimilis (group C), and S. mitis (viridans group) that were examined; nor were cores observed in single strains of Staphylococcus aureus, Escherichia coli, and Bacillus megaterium. Cores may be useful, therefore, in identification of group D streptococci. For preservation and rapid recognition of cores, a glutaraldehyde-osmium tetroxide sequence of fixation appears superior to the osmium tetroxide method often employed in processing bacteria for electron microscopy.

Bacillus megaterium↗

PubMed1998

Streptococcus viridans bacteremia following autologous peripheral blood stem cell transplantation.

A retrospective evaluation of 200 consecutive recipients of autologous peripheral blood stem cell transplantation was conducted to ascertain the incidence and outcome of Streptococcus viridans bacteremia as well as to determine the role of prophylactic ampicillin therapy in the peri-transplant setting. Viridans streptococci were isolated from the blood of 35 individuals at a median of 6 days (range 2-8 days) following stem cell infusion. The most common isolates were S. sanguis and S. mitis. All patients received ciprofloxacin orally during the peri-transplant period. Additionally, 79 patients received oral ampicillin prophylactically against gram-positive cocci. Although none of the patients suffered a fatal outcome, three individuals developed respiratory compromise requiring mechanical ventilation. Female sex proved to be the only independent risk factor for viridans streptococcal bacteremia (P=0.04). The shorter duration of neutropenia observed after stem cell transplantation did not impact on the incidence of S. viridans infections. Moreover, the prophylactic use of ampicillin failed to decrease the incidence of viridans sepsis and selected out organisms that were resistant to beta-lactam antibiotics.

Adolescent↗

PubMed2003

Longitudinal study of the influence of removable partial denture and chemical control on the levels of Streptococcus mutans in saliva.

Some studies have evaluated the salivary levels of mutans streptococci (MS) in removable partial denture (RPD) users. Saliva samples (2.0 mL) were obtained from 31 patients in six periods: (T0): immediately before installation of RPD; (T8): 8 days after T0; (T48): 48 days after T0; (T92): 92 days after T0; (T140): 140 days after T0 and (T189): 189 days after T0. The samples were vortexed and serially diluted from 10(-1) to 10(-6) in 0.05 m phosphate buffer (pH 7.4). From each dilution, 0.025 mL was plated on Mitis Salivarius Bacitracin (MSB). The plates were incubated in 5% CO2 at 37 degrees C for 72 h. There was an increase (t-test, P < 0.05) in the number of MS between periods T0 and T48 (mean/s.d., CFU mL(-1) of saliva): T0: 2.26/4.43 x 10(6) and T48: 0.47/1.48 x 10(8). After this, intensive treatment with CHX was accomplished in 29 patients. Saliva samples were obtained after treatment in four periods: (T24 h): 24 h after T0; (T14): 14 days after T24 h; (T28): 28 days after T24 h, and (T63): 63 days after T24 h. The number of MS in saliva did not decrease (t-test, P > 0.05). A new CHX formulation was applied in 15 patients. Saliva samples were obtained in periods: (T0): before new CHX application; (T24 h): 24 h after T0 and (T82): 82 days after T0. The new CHX reduced MS levels in saliva: (mean/s.d., CFU mL(-1) of saliva): T0: 6.64/8.47 x 10(6) and T24 h: 3.2/4.27 x 10(5) (sign rank, P < 0.05). In conclusion, there was a significant increase in the number of MS in saliva after the installation of RPD. The intensive treatment with a properly formulated CHX was effective in the reduction of MS, between 24 h and 82 days after its application.

Chlorhexidine↗

PubMed2000

Profile of subgingival microbiota in children with primary dentition.

Eruption of primary teeth has a great influence on the oral environment by providing suitable niches for bacterial colonization. The aim of the study was to investigate the composition of the subgingival microbiota of primary incisors, canines and molars in 40 systemically healthy children aged 4-5 yr, chosen randomly. Subgingival plaque samples were taken from the mesiobuccal sites of primary incisors (61, 81), canines (53, 73) and molars (64, 84). The samples were cultured for bacterial isolation anaerobically and in 10% CO2 plus air using selective and non-selective media. Forty-one different microbial species were isolated. Gemella morbillorum and Peptostreptococcus magnus were statistically significantly more frequently detected in incisors while P. micros, Streptococcus intermedius, Bacteroides forsythus, Fusobacterium nucleatum, Prevotella loeschei, P. melaninogenica and Selenomonas sputigena were more frequently detected in molars. The bacterial species S. constellatus, G. morbillorum and P. magnus were isolated in greater numbers in incisors and P. micros, S. intermedius, Campylobacter concisus, Bacteroides egertheii, B. forsythus, P. oralis and S. sputigena were isolated in greater numbers in molars, respectively. Cluster analysis revealed 4 clusters in which 6-7 bacterial species were elevated above mean levels. Cluster I was predominated by S. constellatus, S. mitis, S. sanguis, G. morbillorum, P. melaninogenica and P. oralis; cluster II was predominated by S. sanguis, Actinomyces naeslundii, Capnocytophaga gingivalis, C. ochracea and P. intermedia; cluster III was predominated by S. mitis, C. ochracea, F. nucleatum, P. loeschei, P. melaninogenica and P. oralis; and finally cluster IV was predominated by S. sanguis, C. gingivalis, Veillonella parvula, Campylobacter gracilis, F. nucleatum and P. intermedia. The bacterial species S. constellatus, P. micros, Pseudoramibacter alactolyticus, Eikenella corrodens and F. nucleatum were associated with non-bleeding sites while S. intermedius, C. concisus, P. intermedia and P. loescheii were found more frequently in bleeding sites.

Actinomyces↗

PubMed1976

Cellular fatty acid composition of Streptococcus mutans and related streptococci.

The cellular fatty acid composition of 18 strains of Streptococcus mutans and 17 isolates of related streptococci were examined by gas-liquid chromatography. The cultures could be divided into two distinct groups on the basis of their fatty acids. The first group, which included S mutans and S salivarius, contained palmitic (16:0), octadecenoic (18:1), stearic (18:0), eicosenoic (20:1), and eicosanoic (20:0) acids. The presence of the two 20-carbon fatty acids distinguished S mutans and S salivarius from all of the other species. Two of the S mutans cultures were further distinguished by the presence of 19-carbon and 21-carbon cyclopropane acids. The second group included S sanguis, S mitis, S uberis, and a culture of Lancefield group C streptococci. The percentages of the major acids (16:0, 18:1, and 18:0) found in these species were essentially identical. A culture of Lancefield group E streptococci contained large amounts of 16:1 and 18:1 and small amounts of two unidentified acids which were not present in any of the other cultures.

Chromatography, Gas↗

PubMed1999

Genetic diversity of the streptococcal competence (com) gene locus.

The com operon of naturally transformable streptococcal species contains three genes, comC, comD, and comE, involved in the regulation of competence. The comC gene encodes a competence-stimulating peptide (CSP) thought to induce competence in the bacterial population at a critical extracellular concentration. The comD and comE genes are believed to encode the transmembrane histidine kinase and response regulator proteins, respectively, of a two-component regulator, with the comD-encoded protein being a receptor for CSP. Here we report on the genetic variability of comC and comD within Streptococcus pneumoniae isolates. Comparative analysis of sequence variations of comC and comD shows that, despite evidence for horizontal gene transfer at this locus and the lack of transformability of many S. pneumoniae strains in the laboratory, there is a clear correlation between the presence of a particular comC allele and the cognate comD allele. These findings effectively rule out the possibility that the presence of noncognate comC and comD alleles may be responsible for the inability to induce competence in many isolates and indicate the importance of a functional com pathway in these isolates. In addition, we describe a number of novel CSPs from disease-associated strains of S. mitis and S. oralis. The CSPs from these isolates are much more closely related to those from S. pneumoniae than to most CSPs previously reported from S. mitis and S. oralis, suggesting that these particular organisms may be a potential source of DNA in recombination events generating the mosaic structures commonly reported in genes of S. pneumoniae that are under strong selective pressure.

Alleles↗

PubMed1986

The intra-oral effect on enamel demineralization of extracellular matrix material synthesized from sucrose by Streptococcus mutans.

The role of extracellular matrix material (EMM) synthesized from sucrose (S) by Streptococcus mutans IB-1600 in altering the demineralizing potential of artificial plaque was evaluated with an intraoral enamel demineralization test (IEDT). The artificial plaque samples were prepared from cells cultivated in Todd-Hewitt broth (THB) supplemented with various S concentrations and by mixing THB-grown cells with increasing proportions of EMM (heat-killed THB + 2% S-cultivated cells). The samples were also evaluated for cell density (DNA content) and acidogenicity in vitro (pH-stat), as well as for in situ pH changes during a 45-minute intra-oral test following a 10% glucose rinse. An increase in the proportion of EMM relative to cell density was associated with an increase in enamel demineralization. This trend reversed when the ratio of cells to EMM was less than 1:19. Experiments involving strains of S. mitis, S. sanguis, and S. salivarius suggested a similar effect of EMM. The intra-oral pH data suggest that the presence of EMM may enhance demineralization by altering diffusion properties of plaque.

Acids↗

PubMed1995

Comparison of phenotypic characteristics, DNA-DNA hybridization results, and results with a commercial rapid biochemical and enzymatic reaction system for identification of viridans group streptococci.

The rapid ID 32 Strep system (bioMérieux, Marcy l'Etoile, France) was evaluated for its ability to identify 21 species of viridans group streptococci; results were compared with DNA-DNA hybridization results and results of conventional physiological tests. A total of 171 strains of the 21 species including 147 clinical strains was analyzed. Of the 156 strains of species included in the database of this system, 136 strains (87%) were correctly identified. Incorrect identification occurred for 13 strains (8%), and no identification was given for 7 strains (5%). It was difficult to differentiate S. mitis and S. oralis accurately with this system. Of the 17 strains identified as S. mitis by the rapid ID 32 Strep system, the results of DNA-DNA hybridization were in agreement for only 3 strains. S. crista and S. parasanguis, which are not included in the database, were identified as S. mitis or S. sanguis or were not identified, but S. parasanguis could probably be identified by using the rapid ID 32 Strep system because the biochemical profile is well characterized for this species. The rapid ID 32 Strep system can be used to differentiate most species for which phenotypic characteristics have been described if the database is revised according to recently reported amended criteria for the identification of viridans group streptococci. However, identification of a few species such as S. mitis and S. oralis is problematic with this system.

Bacterial Typing Techniques↗

PubMed1998

Molecular evolution of rifampicin resistance in Streptococcus pneumoniae.

Rifampicin resistance has arisen in several different species of bacteria because of alterations to one or more regions in the target of the antibiotic, the beta-subunit of RNA polymerase encoded by rpoB. Nucleotide sequence analysis of a 270 bp fragment of rpoB from 16 clinical rifampicin-susceptible isolates of Streptococcus pneumoniae, 8 clinical rifampicin-resistant isolates, and 3 spontaneous rifampicin-resistant mutants, has revealed that, as with previously examined species, point mutations within the cluster I region of rpoB, at sites encoding Asp516 and HiS526, also confer resistance to rifampicin in this important human pathogen. Moreover, the residues within cluster I, that were altered within the rifampicin-resistant mutants of S. pneumoniae, were in the same position as those previously found to alter in resistant isolates of Escherichia coli and Mycobacterium tuberculosis. Sequence analysis of rpoB, both from these isolates of S. pneumoniae and from two strains of S. mitis, reveals that, among a number of clinical isolates, resistance to rifampicin in S. pneumoniae has arisen by point mutation. However, the nucleotide sequence of rpoB from one isolate examined suggests that interspecies gene transfer may also have played a role in the evolution of rifampicin-resistance in S. pneumoniae.

Amino Acid Sequence↗

PubMed1979

Biological activity of secretory IgA--comparison of agglutinating specificity with SIgA and Ca++-dependent agglutinin--.

Ca++-dependent bacterial agglutinin was isolated from the human parotid saliva by gel filtration of Sepharose 2B. The agglutinin appeared in the void volume fractions. Treatment of this agglutinin with EDTA resulted in the loss of its ability to agglutinate the bacteria. Standardized solutions of the agglutinin were tested for the agglutinating activity against 18 strains of oral indigenous bacteria. It was found that the agglutinin exhibited varying degrees of activity to all the test strains and the activity was generally higher than that of secretory IgA. It was also found that the receptor sites of the Ca++-dependent agglutinin for Str. sanguis and Str. mitis were identical whereas SIgA contained a number of available binding sites, for different bacterial species.

Adult↗