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PubMed2006

Deep neck infection complicating lymphadenitis caused by Streptococcus intermedius in an immunocompetent child.

BACKGROUND: Streptococcus intermedius belongs to the Streptococcus anginosus group. It is part of the normal flora of the human mouth, but it can be etiologically associated with deep-site infections. CASE PRESENTATION: We present a case of deep neck infection complicating Streptococcus intermedius lymphadenitis, which developed in an immunocompetent 14-year-old boy with a history of recent dental work. The infection was ultimately eradicated by a combined medical and surgical approach. CONCLUSION: Our report suggests that combined medical and surgical therapy is essential for the complete resolution of deep infections caused by Streptococcus intermedius. Molecular biological techniques can be useful in guiding the diagnostic investigation and providing insight into the possibility of occult abscesses, which are particularly common with Streptococcus intermedius infections.

Adolescent↗

PubMed1995

Hydrolytic enzymes of Streptococcus anginosus, Streptococcus constellatus and Streptococcus intermedius in relation to infection.

A collection of 518 'Streptococcus milleri' strains was tested for the presence of hydrolytic enzymes, and the results were related to the clinical significance of the strains. Ribonuclease activity was equally distributed among the three species while hyaluronidase activity was linked to Streptococcus intermedius and Streptococcus constellatus. Both enzymes were not significantly associated with infection-related strains. Deoxyribonuclease and chondroitin sulfatase activity tended to be present more frequently in Streptococcus intermedius and Streptococcus constellatus and was associated with infection-related strains (p < 0.001).

Chondroitin Sulfates↗

PubMed1994

Degradation of hyaluronate by Streptococcus intermedius strain UNS 35.

Streptococcus intermedius strain UNS 35, a brain abscess isolate, produced extracellular hyaluronidase when grown in brain heart infusion broth. Chemical assays with this enzyme indicated that hyaluronate depolymerisation resulted in the formation of carbohydrate moieties with N-acetylglucosamine at the reducing terminal and containing an unsaturated carbon-carbon double bond. The nature of the products of this hyaluronidase were investigated further by high-field (400 MHz) proton (1H) NMR spectroscopy. Treatment of hyaluronate with the enzyme resulted in a series of new, sharp resonances in spectra (acetamido methyl group singlets located at 2.03 and 2.07 ppm, sugar ring proton multiplets in the 3.5-4.2 ppm chemical shift range, and doublets at 5.16 and 5.87 ppm) characteristic of low-M(r) oligosaccharide species, predominantly those containing glucuronosyl residues with delta 4,5-carbon-carbon double bonds. Comparison of spectra acquired from hyaluronidase-treated samples with that of an authentic sample of 4-deoxy-L-threo-hex-4-enopyranosyluronic-acid-N-acetylglucosamine (delta UA GlcNAc) indicated that this disaccharide was a major product arising from the actions of this enzyme. When used in minimal media, hyaluronate supported growth of S. intermedius, with lactate as the major metabolic end-product.

Carbohydrate Sequence↗

PubMed1979

Evidence for the synthesis and release of strongly immunosuppressive, noncytotoxic substances by Streptococcus intermedius.

Products secreted by Streptococcus intermedius were studied for their effects on the immune response. Three different preparations of crude extracellular products from S. intermedius (CEP-Si) were found to have powerful suppressor activity in vitro as shown by inhibition of human lymphocyte proliferation (uptake of [3H]thymidine) and protein synthesis in response to a wide variety of stimulants, including mitogens and antigens, and suppression of plaque formation by human cells in response to sheep erythrocytes. CEP-Si was noncytotoxic, because cells incubated with high concentrations of CEP-Si and subsequently washed were viable and recovered their ability to respond to mitogens, and because leukocyte migration was not inhibited by CEP-Si, nor was the release of leukocyte migration inhibitory factor from sensitized lymphocytes. The possibility of antigen or mitogen competition was excluded. The effects of CEP-Si in vitro were time dependent and did not require the presence of monocytes. Cells pretreated with CEP-Si and then washed suppressed plaque formation by fresh autologous cells in highly stimulated cultures. CEP-Si injected into C57BL/6 mice also strongly suppressed their immune response to sheep erythrocytes, and the in vivo suppression was correlated with the effects of CEP-Si in vitro.

Animals↗

PubMed1997

Experimental endocarditis induction and platelet aggregation by Streptococcus anginosus, Streptococcus constellatus and Streptococcus intermedius.

A total of 18 'Streptococcus milleri' strains including the ATCC type strains of Streptococcus anginosus, Streptococcus constellatus and Streptococcus intermedius were compared with Streptococcus oralis ATCC10557 for their ability to induce infective endocarditis in catheterized rats. Three days after intravenous injection of 10(8) colony-forming units all 8 S. anginosus strains tested produced infective vegetations and bacteremia in almost all rats whereas 5 S. constellatus strains and the S. oralis strain produced infective vegetations and bacteremia less frequently and 5 S. intermedius strains only occasionally. The vegetations infected with the S. anginosus strains harbored microbial cells in significantly higher numbers that those with the other strains. No strong correlation was found between the endocardial infectivity and platelet-aggregating capacity of these strains. The platelet-aggregating strains were members of the Lancefield groups F and G or ungroupable but not of group A or C.

Animals↗

PubMed2001

Expression and functional properties of the Streptococcus intermedius surface protein antigen I/II.

Streptococcus intermedius is associated with deep-seated purulent infections. In this study, we investigated expression and functional activities of antigen I/II in S. intermedius. The S. intermedius antigen I/II appeared to be cell surface associated, with a molecular mass of approximately 160 kDa. Northern blotting indicated that the S. intermedius NCTC 11324 antigen I/II gene was transcribed as a monocistronic message. Maximum expression was seen during the early exponential phase. Insertional inactivation of the antigen I/II gene resulted in reduced hydrophobicity during early exponential phase, whereas no effect was detected during mid- and late exponential phases. Binding to human fibronectin and laminin was reduced in the isogenic mutant, whereas binding to human collagen types I and IV and to rat collagen type I was not significant for either the wild type or the mutant. Compared to the wild type, the capacity of the isogenic mutant to induce interleukin 8 (IL-8) release by THP-1 monocytic cells was significantly reduced. The results indicate that the S. intermedius antigen I/II is involved in adhesion to human receptors and in IL-8 induction.

Adhesins, Bacterial↗

PubMed1993

Albumin-binding proteins on the surface of the Streptococcus milleri group and characterization of the albumin receptor of Streptococcus intermedius C5.

Members of the Streptococcus milleri group (SMG) that react with Lancefield group C antisera were shown to bind large amounts of albumin although there was no direct relation between these two properties as polyclonal antisera to Lancefield group C antigen did not prevent the binding of albumin. There was a specificity for albumin binding, with albumin from man, monkeys, cat, dog and mouse being bound to a greater degree than albumin from cow, horse, goat or rabbit. Gold-labelled albumin was shown to be located close to the surface of strains by transmission electron microscopy. A cell-surface protein of M(r) 24,000, which was liberated by lysozyme treatment of cells, was shown to be the cell-surface receptor on Streptococcus intermedius C5. The receptor was physically dissimilar from protein G, an albumin- and IgG-binding protein of 'large-colony' Lancefield group C and G streptococci.

Animals↗

PubMed1990

Serogrouping of oral Streptococcus intermedius.

Employing twenty fresh oral isolates of Streptococcus intermedius, studies were carried out to characterize serological relations among the isolates and also between the isolates and the strains of bacterial species closely related to S. intermedius. The Rantz-Randall extracts from the cells were used as antigens. The anti-rabbit serum raised against S. intermedius ATCC 27335T reacted with the cell extracts from only three strains of the isolates, which were designated serogroup I strains. The other isolates were classified into four serogroups, I, III, IV, and V, which specifically reacted with the cell extracts from the homologous serogroup strains. However, the serogroup II antiserum formed in immunodiffusion a common precipitin line between the extracts from the cells of serogroups II and I. The serogroups I, III, IV, and V antisera reacted with none of the extracts from the bacterial cells closely related to S. intermedius, which included Streptococcus anginosus ATCC 33397T, Streptococcus constellatus ATCC 27823T, three NCTC strains of "Streptococcus milleri," and three ATCC strains of Streptococcus MG. The precipitin line formed by the homologous reaction of the serogroup II antiserum was found to be a reaction of identity with that formed by the extract from "S. milleri" NCTC 10708. Conversely, the antiserum against NCTC 10708 strain did not react with the cell extracts of serogroup II.

Animals↗

PubMed2003

Purification of saliva agglutinin of Streptococcus intermedius and its association with bacterial aggregation and adherence.

Streptococcus intermedius strain 1208-1 cells were aggregated in the presence of saliva. The saliva agglutinin was purified by centrifugation, filtration, and gel filtration. SDS-PAGE analyses indicated that the purified agglutinin consisted of two high-molecular-mass proteins. Aggregation was dependent on calcium over pH 5.5, with 1 mM being the most effective concentration. Boiling inactivated purified agglutinin. S. intermedius strain 3 and Streptococcus mutans strain 1 were aggregated in the purified agglutinin. After adsorption with strain 1208-1 cells, the saliva sample did not exhibit any aggregation activity, and the agglutinin bands were no longer visible by SDS-PAGE. Adherence analyses demonstrated that the purified agglutinin immobilized on the surfaces of polystyrene wells, actinomyces cells, and apatite beads accounted for the binding of streptococcus cells. Agglutinin also effectively inhibited adherence to apatite beads coated with native saliva.

Actinomyces↗

PubMed1999

Brain abscess caused by Streptococcus intermedius: two case reports.

BACKGROUND: Although Streptococcus intermedius has been recognized as an important pathogen for abscess formation outside the central nervous System, the Streptococcus milleri group, of which it is a member, has not been recognized as a specific pathogen for brain abscess, often thought to be caused by Streptococcus viridans, which includes other streptococcal species. CASE DESCRIPTION: Two cases of brain abscess in the left frontal lobe caused by S. intermedius, which responded well to antimicrobial treatment combined with needle aspiration, are presented. In the first patient, the predisposing disease was paranasal sinusitis of the frontal and ethmoid sinuses. In the second patient, the source of the pathogen was not detected despite extensive examination. The patients underwent aspiration of pus under ultrasound guidance in the first patient, and via a computed tomography-guided stereotactic procedure in the second patient. They subsequently received appropriate antimicrobial therapy against S. intermedius isolated from the pus culture. Both patients were discharged without any neurological deficits. CONCLUSION: It is important to recognize S. intermedius as a pathogen of brain abscess, and to be aware of its predisposing factors, i.e., mucosal disturbance and liver abscess.

Adolescent↗

PubMedDate not supplied

Evidence for the generation of specific T suppressor lymphocytes by Streptococcus intermedius.

Crude extracellular products of the Streptococcus intermedius "CEP-Si" were able to strongly decrease the in vitro proliferation of stimulated human peripheral blood mononuclear cells (HPBMC) when evaluated by (3H)-thymidine and (3H)-leucine uptake. On the other hand, CEP-Si only slightly decreased this proliferation when HPBMC were either not stimulated or cultured in poor conditions or immature cells, i.e. thymocytes were used as target instead. Also in vivo CEP-Si was ineffective when target cells were not highly reactive. Both in vivo and in vitro, the effect of CEP-Si was proportional to the time of contact with the target cells. The dynamics of the effects of CEP-Si suggest the generation of "something" ("suppressor cells") which cause an abrupt drop in the values of (3H)-thymidine uptake rather than a progressive decrease of the values, which could indicate a loss effector or helper cells. On the other hand, CEP-Si suppressed the in vitro primary immunization of human HPBMC against SRBC and, furthermore, human HPBMC incubated with CEP-Si were able to suppress the primary immune response against SRBC of, CEP-Si untreated, HPBMC. In some instances of insufficient time of contact of CEP-Si with the target cells, an enhancement of the immune response was observed both in vivo and in vitro. Moreover, the histological pattern of the spleens of C57 BL/6 mice injected with semipurified products of CEP-Si were consistent with an adjuvant-like effect. Finally, the target HPBMC for the semipurified products of CEP-Si acquired the ultrastructural and antigenic characteristics of suppressor T lymphocytes.

Animals↗

PubMed2002

An in vitro comparison of the bactericidal efficacy of lethal photosensitization or sodium hyphochlorite irrigation on Streptococcus intermedius biofilms in root canals.

AIM: To compare the bacterial killing of Streptococcus intermedius biofilms in root canals using lethal photosensitization with various combinations of photosensitizer concentration and laser light dose or 3% sodium hypochlorite (NaOCl) irrigation. METHODOLOGY: Extracted teeth (n = 35) with single canals were selected and the canals prepared to apical size 25 with a 10% taper. The teeth were autoclaved and the canals inoculated with Streptococcus intermedius in brain heart infusion broth and were incubated for 48 h to allow a biofilm to form. The teeth were then subjected to 3% NaOCl irrigation (n = 4) or lethal photosensitization using combinations of a range of toluidine blue O (TBO) photosensitizer concentrations (12.5, 25, 50, 100 microgram/mL-1) and light doses (60, 90, 120, 300, 600 s equivalent to energy doses of 2.1-21 J) using a 35-mW helium-neon low power laser targeted at the access cavity (n = 4 for each combination). Controls consisted of laser light only (TBO = 0 microgram/mL-1) (n = 4), TBO only (light dose = 0 s) (n = 4), and no treatment (positive control n = 17). Following treatment the canal contents were sampled with sterile paper points, the sample was dispersed in transport medium, serially diluted and cultured on blood agar to determine the number of colony forming units (CFU). RESULTS: The combination of 100 microgram/mL-1 TBO and 600 s (21 J) of laser energy achieved maximum reduction in recovered viable bacteria (5 log10 CFU). TBO at low concentrations (< or =50 microgram/mL-1) was not bactericidal but treatment with 100 microgram/mL-1 TBO alone reduced recovered viable bacteria by 3 log10 CFU. Laser light alone had limited bactericidal effect. No viable bacteria were recovered following treatment with 3% NaOCl. CONCLUSIONS: The combined use of a photosensitizing agent and a low power laser directed at the access cavity was bactericidal to S. intermedius biofilms in root canals but was unable to achieve total kill, unlike 3% NaOCl.

Biofilms↗

PubMed2005

Involvement of antigen I/II surface proteins in Streptococcus mutans and Streptococcus intermedius biofilm formation.

BACKGROUND/AIM: Dental diseases are caused by microorganisms organized in biofilms. Streptococcus mutans and Streptococcus intermedius are commensals of the human oral cavity. S. mutans is associated with caries, whereas S. intermedius is associated with purulent infections. Oral streptococci including S. mutants and S. intermedius express a family of surface proteins termed antigen I/II (Ag I/II). Ag I/II is implicated in adhesion; however, its role in biofilm formation has not yet been investigated. METHODS: By using isogenic Ag I/II-deficient mutants of S. mutans and S. intermedius we studied the influence of Ag I/II on in vitro biofilm formation. Biofilm was quantified in polystyrene microtiter plates and visualized by scanning electron microscopy. Ag I/II expression in planktonic and biofilm cells, as well as in the presence or absence of saliva was investigated by immunoblotting. RESULTS: In the presence of saliva, the Ag I/II-deficient mutants formed 65% less biofilm than the wild-types. In the absence of saliva, no difference was observed in S. mutans, whereas the S. intermedius Ag I/II mutant formed 41% less biofilm. Ag I/II expression was reduced in the presence of saliva. No differences in expression were observed between biofilm and planktonic cells. CONCLUSION: The results indicated that Ag I/II may be important during biofilm formation particularly in the presence of saliva. These findings may provide useful information regarding the importance of Ag I/II in biofilm formation and in the search of new strategies to control biofilm-mediated infections.

Bacterial Adhesion↗

PubMed1986

Strong mitogenic effect for murine B lymphocytes of an immunosuppressor substance released by Streptococcus intermedius.

A noncytotoxic protein substance, produced by Streptococcus intermedius, with very potent immunosuppressive properties (F3'EP-Si) was tested for lymphocyte mitogenic activity. Although devoid of T-cell mitogenicity, F3'EP-Si stimulated proliferation and led to high numbers of plaque-forming cells in cultures of normal or T-cell-depleted, small or large splenic B cells from both lipopolysaccharide-responding and -nonresponding mice. The B-cell mitogenic activity of F3'EP-Si was quantitatively comparable to that of lipopolysaccharide, and the simultaneous exposure to both mitogens stimulated additive B-cell responses. Injection of F3'EP-Si into normal mice resulted in increased numbers of spleen cells, higher rates of mitotic activity, and very large numbers of plaque-forming cells, predominantly of the immunoglobulin G2a and -b isotypes. In preliminary experiments, the analysis of surface markers among the lymphocytes participating in the blastogenic response in vivo revealed a T-cell component in the response to F3'EP-Si. These observations are discussed in the context of the immunosuppressive activity of this and other microbial substances.

Animals↗

PubMed1995

Streptococcus anginosus, Streptococcus constellatus and Streptococcus intermedius. Clinical relevance, hemolytic and serologic characteristics.

A collection of 518 "Streptococcus milleri" isolates recovered from clinical specimens was identified to the species level according to recently established criteria. Streptococcus anginosus was the most frequently isolated species (59.3%), followed by S constellatus (30.3%) and S intermedius (10.4%). One third (34%) of all isolates were beta-hemolytic. The majority of S anginosus isolates were nonhemolytic, carried Lancefield group F, or were nongroupable. Most of the S constellatus isolates were beta-hemolytic, as well as 16.6% of S intermedius strains. Streptococcus anginosus was recovered more often from the genital and urinary tracts and S constellatus was recovered from the thorax. Streptococcus intermedius was mostly found in the head and neck area, but was also isolated from the abdomen and the skin, bone, and soft tissue. Streptococcus intermedius and nonhemolytic isolates were recovered most often from abscess-related specimens.

Adolescent↗

PubMed2006

Streptococcus intermedius: an unusual cause of a primary empyema.

Despite the evolution of modern antibiotics, pleural space infection remains a common illness with significant morbidity and mortality. Every year up to 60 percent of the 1.2 million patients in the United States who present with community-acquired pneumonia develop parapneumonic pleural effusions. Few of these parapneumonic effusions progress to an empyema. Interestingly, in about 10 percent of the cases of empyema, no underlying pulmonary infection can be identified. These pleural space infections are called primary empyemas. We present a patient with a primary empyema caused by Streptococcus intermedius. Relatively few studies have investigated primary empyema caused Streptococcus intermedius. This case presentation serves as a reminder to the clinician about primary empyema caused by this micro-organism.

Anti-Bacterial Agents↗

PubMed1990

Genetic and physiological characteristics of oral Streptococcus intermedius.

The taxonomic relationships among strains of oral Streptococcus intermedius and the related streptococci were determined by G + C mol%, DNA-DNA hydridization, phenotypical and serological tests. As to the results, group 1 strains of S. intermedius including the type strain ATCC 27335 and five isolates behaved distinctively with respect to genetic, phenotypic and serological characteristics compared with group 2 strains of S. intermedius including ATCC 31412 and two isolates. Therefore, nine strains of oral S. intermedius could be separated at least into two homology groups.

Chromatography, High Pressure Liquid↗

PubMed1989

[Taxonomic studies of the Streptococcus intermedius strains isolated from human oral cavities].

Human oral isolates of Streptococcus intermedius, which were biochemically identified, have been classified into 5-Serogroups (I-V). Selecting some representive stock cultures together with the type strain ATCC 27335, comparisons were carried out between them in terms of cell extractable proteins, G + C mol% values, DNA-DNA homology and DNA restriction fragments. Since the taxon of S. intermedius has not been clarified, comparison was also made between the above strains and the type strains of the "Streptococcus anginosus-milleri Group", Streptococcus anginosus, "Streptococcus milleri" and Streptococcus constellatus, which were thought to be related to S. intermedius. 1. G + C mol% of S. intermedius ATCC 27335 was 38.0 +/- 0.28. The values of all the isolates tested ranged from 37.0 to 38.8. On the other hand, the values of the type strains of the "S. anginosus-milleri Group" were 38.0-38.8. 2. Under stringent conditions of DNA-DNA hybridization, all the isolates showed more than 66.7% homology with S. intermedius ATCC 27335, demonstrating that these strains belonged to the same species. On the other hand, S. anginosus ATCC 33397, "S. milleri" NCTC 11169 and S. constellatus ATCC 27823 hybridized at levels of 50%, 53% and 28%, respectively. Consequently, it was impossible to classify these strains as being the same species as S. intermedius. 3. When the DNA restriction fragments were compared by PAGE, the strains of Serogroups I and V showed the same pattern, respectively. The strains of Serogroups II and III, however, showed two different patterns, and these of Serogroup IV showed five different patterns. DNA fragments specific to S. intermedius could not be identified. 4. When cell extractable groups were compared by SDS-PAGE, the strains of Serogroups I and V showed identical patterns. The strains of Serogroup III showed 2 different patterns and those of Serogroup IV showed 5 patterns. These results reflected those of the DNA restriction analysis. However, the strains of Serogroup II showed the same protein pattern, although 2 different patterns were observed in DNA restriction fragments. Unique proteins, which were not detected in the proteins extracted from the type strains of the "S. anginosus-milleri Group", were observed in the cell proteins of S. intermedius strains. 5. The results of DNA-DNA hybridization and the existence of unique extractable proteins together with the chondroitinase productivity suggest that the strains of S. intermedius might represent a particular taxon among the strains of the "S. anginosus-milleri Group".(ABSTRACT TRUNCATED AT 400 WORDS)

Humans↗