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PubMed1986

New test system for identification of Aerococcus, Enterococcus, and Streptococcus species.

A total of 244 strains of Aerococcus, Enterococcus, and Streptococcus species were tested by the RapID STR system (Innovative Diagnostic Systems Inc., Atlanta, Ga.) for identification. Strains were identified without additional tests or with additional conventional tests suggested by the IDS compendium manual. Our data indicate that the RapID STR system identifies 89% of the beta-hemolytic Streptococcus species if serological procedures are used in conjunction with the rapid physiological procedures. Of the group D streptococci, 98% of the Enterococcus species and 100% of the group D non-Enterococcus species were correctly identified. Of the commonly occurring viridans group Streptococcus species, 93% were correctly identified, and 79% of the less frequently occurring viridans group Streptococcus species were correctly identified. All of the Streptococcus pneumoniae and Aerococcus strains tested were correctly identified.

Humans↗
PubMed1994

Detection of Streptococcus pneumoniae DNA in blood cultures by PCR.

We have developed a PCR assay, with primers derived from the autolysin (lyt) gene, for the detection of Streptococcus pneumoniae DNA in blood cultures. The predicted fragment of 247 bp was detected in all strains of pneumococci, embracing 12 different serotypes that were tested. Although DNA extracted from four viridans streptococci spp. Streptococcus oralis, Streptococcus mitis, Streptococcus sanguis, and Streptococcus parasanguis) gave amplification products, these were quite different from the predicted fragment for S. pneumoniae. Application of the assay for diagnosis of septicemia caused by S. pneumoniae showed concordance between PCR and culture results. However, on four occasions PCR was positive in supernatants from both paired culture bottles while pneumococci were cultured from only one. Performing PCR on negative cultures in controlled studies such as vaccine trials may provide a sensitive tool for increasing case detection.

Base Sequence↗
PubMed1986

Identification of a Streptococcus sanguis receptor for salivary agglutinins.

The objective of this study was to characterize a fraction from oral streptococci containing receptor activity for salivary agglutinin molecules. Several species and strains of streptococci were disrupted in a Ribi press. The supernatant was nuclease-treated and subjected to differential centrifugation. Receptor activity in the fractions was measured by the inhibition of saliva-mediated bacterial aggregation. In addition, bacterial strains were tested for their ability to aggregate and to deplete saliva of agglutinin activity. Three patterns of activity were observed: Streptococcus sanguis M5 depleted saliva of agglutinin activity and aggregated well; Streptococcus sanguis CC5A depleted saliva of agglutinin but did not aggregate well; and Streptococcus faecalis S-161 neither depleted saliva of agglutinin nor did it aggregate. The 105,000 g supernatant fractions derived from Ribi-disrupted Streptococcus sanguis M5 and CC5A, but not from Streptococcus faecalis, showed dose-dependent inhibition of saliva-mediated aggregation. This inhibitory activity was non-dialyzable, had the same heat and trypsin sensitivity as that seen with intact bacteria, and was not due to enzymatic digestion of the salivary agglutinin. Iso-electric focusing revealed a single active region with a pI of 5.5 which was clearly separated from the bulk of the bacterial proteins.

Agglutination↗
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↗
PubMed1993

Streptococcus mitis septicemia in leukemia patients; clinical features and outcome.

The frequency of streptococcal infections has been reported to be increasing. To determine the significance of such infections complicating treatment of leukemia, we studied the incidence and clinical features of Streptococcus mitis septicemia among 51 leukemia patients in our department. During 166 consecutive treatment courses for leukemia, eight episodes of Streptococcus mitis septicemia were observed in 35 septicemic patients. In seven out of eight episodes (88%), severe mucositis developed after aggressive chemotherapy, suggesting that oral mucosa might be the site of entry for Streptococcus mitis. The isolates were sensitive to imipenam/cilastatin and cefuzonam, and were relatively resistant to amikacin. Although none of the patients died of Streptococcus mitis septicemia, life-threatening adult respiratory distress syndrome (ARDS) developed in two independent treatment courses. We should thus be aware of the risk of ARDS in patients with Streptococcus mitis septicemia.

Adolescent↗
PubMedDate not supplied

[Streptococcus suis infection--clinical manifestations].

INTRODUCTION: Streptococcus suis is a bacterium causing a disease in pigs and rarely in humans. This zoonosis is mostly found as a sporadic disease in individuals that were in contact with the affected or infected pigs: farmers, veterinarians and workers engaged in fresh pork processing. It is assumed that the bacterium enters the body through a cut abrasion in the skin. Initially, the condition resembles a flu, followed by signs of bacteriemia and sepsis. The most frequent clinical manifestation of Streptococcus suis infection is meningitis, leading to hearing loss in over 75% of patients, and subsequent arthritis, endophtalmitis, endocarditis and pneumonia. Toxic shock syndrome with hemorhagic manifestations rarely develops. MATERIAL AND METHODS: This study included five male patients aged 22 to 63 years treated in the Intensive Care Unit of the Institute of Infectious and Tropical Diseases in Belgrade, due to Streptococcus suis infection. The aim of this study was to point to the existence of this bacteria in our environment, to describe clinical manifestations of the disease and to point out the importance of its prevention. RESULTS: All patients had epidemiological evidence of being in contact with pork meat. There were no data about diseased pigs. The estimated incubation period was 4 to 8 days. All patients had meningeal signs. Clinical symptoms included shivering, fever, vomiting, headache, malaise, vertigo and tinitus. Three patients presented with alerterd level of awarrness. Four patients developed very severe bilateral hearing impairment, whereas one endophtalmtis and one developed endocarditis. The cerebrospinal fluid (CSF) was opalescent in four patients, and only one patient presented with clear CSF. CSF examination showed typical changes characteristic for bacterial meningitis. Streptoccocus suis was isolated in CSF in all patients, and in one patient the bacteria was isolated in blood as well. All patients underwent treatement with II and III generation cephalosporins and one with one aminoglycosides. All patients were cured, but 4 of them developed sequelae like permanent sensorineural deafness and mild ataxia. CONCLUSIONS: Streptococcus suis infection is present as a zoonosis in pigs, while humans are contracted occasionaly, most frequently related to occupational risk. In cases with bacterial meningitis with sepsis and hearing loss, Streptococcus suis infections must be suspected. Effective prevention requires collaboration between epidemiologists, veterinarians and human medicine physicians.

Adult↗
PubMed2004

[Erythromycin-resistant Streptococcus pyogenes].

Streptococcus pyogenes is the most prevalent cause of tonsillopharyngitis in children. The drug of choice for infections caused by this microorganism is penicillin. The problem of treating such infections arises when erythromycin-resistant strains occur. The aim of the study was to determine the prevalence of Streptococcus pyogenes resistant to erythromycin. The organism was recovered from the pharynx of children hospitalized or treated on outpatient basis at the University Children's Hospital in Belgrade. Streptococcus pyogenes was identified on blood agar, using bacitracin disc, and confirmed by latex agglutination test (Slidex bioMerieux). Disc diffusion test was carried out to estimate the penicillin resistance. Erythromycin disc was used as screening method to detect erythromycin-resistant Streptococcus pyogenes. MIC for erythromycin was performed by broth dilution method. In the study period from January 2001 to December 2003, all 1100 isolates of Streptococcus pyogenes had usual level of penicillin sensitivity. In 2001, only 0.45% of isolates were erythromycin-resistant. In 2002, erythromycin resistance was 0.63%, while in 2003, it was 1.09%. MIC for erythromycin was from 1 to 128 mg/l. Three strains had constitutive and one strain had inducible resistance to clindamycin. According to the results, our conclusion is that, despite sensitivity to penicillin, resistance to macrolides is the emerging phenomenon. Reasonable use of macrolide antibiotics is necessary to maintain the resistance at the lowest level.

Anti-Bacterial Agents↗
PubMed1983

Contribution of Streptococcus thermophilus to growth-stimulating effect of yogurt on rats.

The origin of the growth-stimulating factor in yogurt was studied in rats fed liquid or freeze-dried diets of milk, yogurt, milks fermented individually by Streptococcus thermophilus and Lactobacillus bulgaricus, milks to which cells of Streptococcus thermophilus and Lactobacillus bulgaricus were added. Diets containing sonicated cells, cell supernatant, and cell fractions also were fed. Milk fermented by Streptococcus thermophilus and milk plus Streptococcus thermophilus cells stimulated growth as effectively as did yogurt. That finding and the absence of stimulation in rats fed Lactobacillus bulgaricus showed that Streptococcus thermophilus is responsible for stimulation of growth by yogurt. Growth was stimulated by an intracellular factor and not by fermentative changes in the milk.

Animals↗
PubMed1984

Compositions and characteristics of strains of Streptococcus bovis.

Streptococcus bovis strains JB1, 26, 581AXY2, 21096C, and 45S1 grew on glucose, maltose, starch, sucrose, cellobiose, and lactose. None of these strains grew on xylose or ribose, but arabinose was a suitable energy source for strains 2109C and K27FF4. All strains grew at 45 degrees C, but incubation at 50 degrees C prevented growth. Growth was permitted in 2% sodium chloride, but 6.5% sodium chloride was inhibitory. Doubling times ranged from 24 to 27 min, and final pH on glucose was approximately 4.6. None of the strains had a requirement for amino acids, and growth was rapid in media containing glucose salts and B vitamins. There was no ammonia production from arginine. All strains showed aminoendopeptidase activity, but there was considerable strain variation. Strain 7H4, reported as Streptococcus bovis, was noticeably different from the other six strains. It had a doubling time that was more than four times as long, and it grew poorly on starch or in the absence of an amino acid source. Six-and-a-half percent sodium chloride was not inhibitory, and it produced ammonia from arginine. Cell morphology was coccoid rather than ovoid. Based on these criteria, classification of strain 7H4 as Streptococcus bovis seemed doubtful. Other experiments with strain 7H4 indicated that Streptococcus bovis was devoid of diaminopimelic acid. In these experiments strain 7H4 contained significant diaminopimelic acid. The six Streptococcus bovis strains all contained diaminopimelic acid as well, but concentration varied.

Animals↗
PubMed1997

Identification of Streptococcus species by randomly amplified polymorphic deoxyribonucleic acid fingerprinting.

Identification of Streptococcus species isolated from bovine milk by randomly amplified polymorphic DNA fingerprinting was evaluated. Bacterial DNA templates were prepared using a standardized method for randomly amplified polymorphic DNA amplification and previously evaluated arbitrary primers. Amplified DNA fragments were visualized by agarose gel electrophoresis and were analyzed by densitometry. Unidentified streptococci (n = 163) that were isolated from mammary secretions of dairy cows were evaluated. The DNA fingerprint patterns of unidentified bacteria were compared using a computerized database that contained DNA fingerprint patterns of test strains. Comparison with the API 20 Strep identification system (bioMérieux Vitek, Inc., Hazelwood, MO) and conventional biochemical tests showed that about 91% of isolates (148 of 163) were identified correctly by DNA fingerprinting. The sensitivity of the DNA fingerprinting technique was 90%, and the specificity was 92%. However, the DNA fingerprinting technique only identified 4 of the 11 species included in the study. Three of the 4 species, Streptococcus uberis, Streptococcus agalactiae, and Streptococcus dysgalactiae, represent the streptococci isolated most frequently from cows with mastitis. The other Streptococcus and Enterococcus species that were not identified by the DNA fingerprinting system are less frequently isolated as causative agents of mastitis. Expanding the DNA fingerprint database would likely increase the sensitivity and specificity of this technique.

Animals↗
PubMedDate not supplied

[Antibiotic sensitivity and treatment recommendations for Streptococcus pneumoniae].

The aims of present paper were to determine the susceptibility of the strains to the most usual antibiotics in clinical practice and to review the current recommendations to guide the most appropriate treatment. During the period october 2000 to september 2002, the patient's data (age and sex), source of the sample, diagnosis and antibiotic susceptibility were collected on Streptococcus pneumoniae isolates from microbiology laboratories in the Navarra region (555.829 inhabitants). Four hundred and sixty five isolates were identified (166 from invasive infections). Generally, isolates from ear swabs were the most resistant to the antimicrobials tested, while those from blood culture were the most susceptible. Of the Streptococcus pneumoniae tested, 43% were resistant to penicillin, 6.1% to amoxicillin and 6.6% to cefotaxime. Of the 36.3% of Streptococcus pneumoniae isolates that were resistant to erythromycin, 85.45% exhibited the MLSB phenotype while the remaining 14.55% presented with the M phenotype. Multiple-resistance was detected in 32.3% of the strains. The antibiotic resistance rates to beta-lactams (specially penicillin, amoxicillin and cefotaxime/ceftrixone) in Streptococcus pneumoniae don't prevent its clinical use for the most of Streptococcus pneumoniae isolated in our area, except for pneumococcal meningitis.

Anti-Bacterial Agents↗
PubMed1999

Self-collection of group B Streptococcus cultures in pregnant women.

OBJECTIVE: This study assesses the sensitivity of self-collected rectovaginal culture specimens for group B Streptococcus by pregnant patients. METHODS: A volunteer sample of 240 pregnant women at 28 weeks gestation self-collected rectovaginal culture swabs to screen for the presence of group B Streptococcus. The patients' physicians collected second specimens for comparison. RESULTS: Twenty-four of 240 women grew group B Streptococcus on at least one culture (incidence, 10%). Twenty physician-collected specimens and 19 patient-collected specimens were positive (83 and 79% sensitivity, respectively). Fifteen patients (62.5%) had both physician-collected and patient-collected cultures grow group B Streptococcus. Cohen's kappa (kappa = 0.75) indicates a high degree of agreement between patient-collected and physician-collected cultures. CONCLUSIONS: Pregnant women are as likely as their attending physicians to obtain positive cultures for group B Streptococcus by self-collection of rectovaginal swabs.

Adult↗
PubMed2000

[Tissue infections caused by group A beta hemolytic Streptococcus in a regional hospital of Talca, Chile].

BACKGROUND: A resurgence of group A beta hemolytic Streptococcus infections such as fasciitis, cellulitis and Streptococcal Toxic Syndrome has been observed recently. AIM: To study the clinical features of patients with group A beta hemolytic Streptococcus infections in a regional hospital. PATIENTS AND METHODS: Retrospective review of medical records of patients notified as having a group A beta hemolytic Streptococcus tissue infection, between 1994 and 1999. RESULTS: Twenty four patients were notified in the period as having a group A beta hemolytic Streptococcus infection and 18 (13 male, mean age 39 tears old) had tissue involvement. Eleven patients had a fasciitis (61%), six had a cellulitis (33%) and 14 patients (77%), a Streptococcal Toxic Shock Syndrome. Eight patients died during hospital stay. The infection portal of entry was identify in 13 patients (the skin in 10 and intramuscular injections in three). Decreased patients had a longer lapse of disease before admission than patients discharged alive (5(range 3h-7 days) and 2.1 (range 6h-5 days) respectively). In seven patients a quick serological test, designed for pharyngeal infections was performed and it was positive in five. Blood cultures were positive in seven patients and in 11, the germ was isolated from the lesions. CONCLUSIONS: As the early diagnosis of group A beta hemolytic Streptococcus tissue infections has a prognostic value, the population should be instructed to recognize early signs and symptoms of these infections.

Adolescent↗
PubMed2001

[Typing of Streptococcus mutans (serotype C) by arbitrarily primed polymerase chain reaction].

OBJECTIVE: To study the relationship between genetic diversity within Streptococcus mutans (C), and dental caries. METHODS: One reference strain (GS5) was used to establish the suitability of primers and the initial AP-PCR conditions. Isolates of Streptococcus mutans (C) were obtained from 19 caries-free and 40 caries-active patients, and were originally isolated on mitis-salivarius-bacitracin agar. Totally 278 isolates were biochemically and serologically confirmed as Streptococcus mutans (C). Chromosomal DNA was extracted from those isolates by Chelex. One random primer, OPA-05 was used as a template in PCR reaction. All amplification reactions were conducted in a volume of 20 microliters containing 2 microliters of 10 x reaction buffer, 200 mumol/L each of dATP, dCTP, dGTP and dTTP and 2.5 units of Taq DNA polymerase. We varied the concentrations of MgCl2 (1.5-4.5 mmol/L), template DNA (2-40 ng), and primer (0.3-0.5 mumol/L) to determine the optical conditions for AP-PCR. The temperature profile in a thermocycler was 35 cycles as follows: 94 degrees C for 1 min, at 36 degrees C for 2 min, at 72 degrees C for 2 min. The initial denaturation was at 94 degrees C for 5 min and the final extension at 72 degrees C for 5 min. RESULTS: The MgCl2 concentration in 4 mmol/L and the primer concentration in 0.5 mumol/L produced clearly distinct and reproducible fingerprints. We found 105 different patterns among the 278 isolates. In high-caries persons more than one genotype isolates of Streptococcus mutans (C) were colonized. CONCLUSIONS: Isolates of Streptococcus mutans (C) exist apparent genetic diversity. The genotypes of isolates might relate to differences in caries susceptibility.

DNA, Bacterial↗
PubMed1998

Relationship between caries status, colony forming units (cfu) of Streptococcus mutans and Snyder caries activity test.

It is a well established fact that dental caries is caused by streptococcus mutans. For qualitative and quantitative analysis of streptococcus mutans, saliva samples are often preferred and are processed according to Kohler and Brathall method. In the present study an attempt is made to relate caries status (caries free, average caries, and rampant caries group) with cfu counts of streptococcus mutans and Snyder test. The streptococcus mutans were isolated using MSB agar and cfu were determined of each individual from different caries groups. The saliva of the same individual was drooled into a culture bottle containing Snyder test agar and extent of colour change was observed after 24, 48, and 72 hours incubated at 37 degrees C. The time and extent of colour change determined the conduciveness of diet. It has been observed that caries free individuals have low cfu count and their diet was mild or moderately conducive, while the individuals having average caries had medium cfu count and their diet was moderately-high conducive. In rampant caries, individuals however the cfu count were high and the diet was highly conducive. In caries free, average caries and rampant caries group 40, 60, and 80 per cent samples showed colour change, in Snyder test up to full length in 72 hours respectively. Thus a definite correlation exists between caries status, cfu count of streptococcus mutans and Snyder caries activity test.

Child↗
PubMed2002

Streptococcus pneumoniae resistance to penicillin and ceftriaxone in a tertiary care center in Saudi Arabia.

OBJECTIVE: The proportion of penicillin and ceftriaxone resistant Streptococcus pneumoniae isolates and associated risk factors varies by geographic areas in the world. We conducted a retrospective study to determine the extent of penicillin and ceftriaxone non-susceptible Streptococcus pneumoniae bacteremia in a tertiary care medical center in the city of Riyadh, Kingdom of Saudi Arabia. METHODS: We reviewed 172 episodes of Streptrococcus pneumoniae bacteremic diseases involving 160 hospitalized patients at King Faisal Specialist Hospital and Research Centre, Riyadh, Kingdom of Saudi Arabia, over a 5 year period between January 1995 through to December 1999. Patients' characteristics and underlying illnesses of those patients with bacteremias and meningitis caused by Streptococccus pneumoniae as well as antimicrobial susceptibility were examined. RESULTS: The majority of patients affected with Streptococcus pneumoniae bacteremia were children <5 years of age (number=91, 53%). Malignant diseases were the main underlying diagnosis in our patient population affected with pneumoncoccal bacteremia (number=46, 27%). Overall (51%) of the isolates were penicillin non-susceptible; of these (7%) were highly resistant. The overall resistance rate to ceftriaxone was 7%. CONCLUSION: With the high prevalence in Streptococcus pneumoniae antimicrobial resistance to penicillin and ceftriaxone, it is important to continue surveillance of infections caused by Streptococcus pneumoniae, and also we recommend that guidelines for treatment and prevention of pneumococcal infection must be addressed by health care and public health agencies.

Adolescent↗
PubMed2002

Increased proliferative response of peripheral blood mononuclear cells and T cells to Streptococcus mutans and glucosyltransferase D antigens in the exacerbation stage of recurrent aphthous ulcerations.

BACKGROUND AND PURPOSE: Cytotoxic T lymphocyte-induced lysis of virus-infected oral epithelial cells has been shown to be a cause of early ulcer formation in recurrent aphthous ulcerations (RAU). To test whether bacteria and their associated antigens are involved in the disease process of RAU, the proliferative response (PR) to different streptococcal species in peripheral blood mononuclear cells (PBMC) and T cells isolated from RAU patients at the exacerbation stage was determined. METHODS: PBMC and T cells were isolated from 39 patients with RAU, 21 patients with erosive oral lichen plaus (EOLP, disease control group), and 22 healthy subjects (normal control group). Streptococcus mutans, Streptococcus sanguis, Streptococcus oralis, Streptococcus gordonii, Streptococcus mitis and their associated antigen, glucosyltransferase D (GtfD), were used to stimulate isolated PBMC and T cells in in vitro proliferation assays. RESULTS: PBMC and T cells isolated from RAU patients at the exacerbation stage showed a significantly higher PR to S. mutans antigen and GtfD than those isolated from EOLP patients or healthy control subjects (p < 0.05). GtfD was a more potent stimulation antigen than S. mutans. However, elevated PRs to S. mutans antigen and GtfD were transient and present only in the exacerbation stage of RAU. These elevated PRs declined to normal levels in the postexacerbation and convalescence stages of RAU. Furthermore, the GtfD-stimulated PR in PBMC and T cells was correlated with the severity of RAU. CONCLUSION: In addition to viral infections, streptococci and their associated antigen, GtfD, may be involved in the disease process of RAU, especially in the exacerbation stage.

Adolescent↗
PubMed2000

[Evaluation of cariogenic potential of Streptococcus mutans isolated from caries-free and -active persons: adherence properties to saliva-coated hydroxyapatite].

OBJECTIVE: In this study, authors used saliva-coated hydroxyapatite to simulate tooth surface in oral cavity to evaluate adherence of different Streptococcus mutans isolated from caries-free and -active persons to saliva-coated hydroxyapatite. METHODS: Streptococcus mutans isolated from people with different carious experiences were divided into two groups: the caried-free group (DMFS = 0) including 19 persons and the caries-active group (DMFS > or = 6) including 40 persons. Totally 105 genotype Streptococcus mutans strains were obtains, including 22 strains from the caries-free group, and 83 strains from the caries-active group. The adhering properties of Streptococcus mutans (serotype c) strains were investigated, and different adhering properties were compared between the caries-free group and the caries-active group in order to find the correlationship between carious experiences and adhering properties of Streptococcus mutans. Saliva-coated hydroxyapatite was used to simulated tooth surface in oral cavity. Streptococci mutans were cultured in TPY liquid medium containing 3H-TDR in the same radioactive concentration. After being cultured in an anaerobic incubator for 18 hours, Streptococci mutans were radiolabelled by 3H-TDR. Saliva-coated hydroxyapatite and bacterial liquid(BSA = 0.52) were mixed for 90 minutes. Samples were assayed by using liquid scintillation counter, and binding abilities of strains were evaluated by the count per minute(cpm). RESULTS: Binding abilities of strains were significantly different in two groups, Caries-active people harbored more Streptococci mutans with high binding abilities(cpm > 2000) than caries-free people did(P < 0.05). The binding abilities to saliva-coated hydroxyapatite were different between strains of differing genotypes isolated from the same person. Each person always harbored one or two strains with high binding abilities(cpm > 2000) in the caries-active group. CONCLUSION: 1. Different genotypes have different adhering properties. 2. In caries-active group, different genotype strains have synergic effects, and adhesion of high binding ability strains cause caries susceptibility. 3. The differences in binding properties of isolates might relate to differences in carious experiences.

Bacterial Adhesion↗