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PubMed2005

[The study of salivary-SIgA reaction to Streptococcus mutans in acid environment].

OBJECTIVE: To test the salivary immunoglobulin A antibody activity to Streptococcus mutans in normal with in acid environment. METHODS: Streptococcus mutans strains were isolated from 20 volunteers, serotyped by biochemical test and PCR, and genotyped by AP-PCR. Unstimulated secretions from submandibular glands and sublingual glands were collected from volunteers by modified collectors. Each identified Streptococcus mutans genotype was cultured in two groups: control group was cultured in BHI broth pH7.2 at 37 degrees C for 2 h; acid shock group were cultured in TYEG broth (pH5.5) at 37 degrees C for 2 h. Analysis of SIgA activity to Streptococcus mutans genotypes in different groups was detected by Western blot. RESULTS: (1) The SIgA of each individual could response to his own Streptococcus mutans strains and the reference strains; (2) The same individual had different SIgA activity to different genotype strains; (3) There were no significant difference between acid groups and control groups, in spite that some bands had strong or weak intensity. CONCLUSIONS: Although Streptococcus mutans could express acid shock proteins in stress, the present study suggests that these new proteins have no qualitative effect on the reaction of SIgA to Streptococcus mutans.

Adult↗
PubMed2006

Streptococcus agalactiae infections in non-pregnant adults: single center experience of a growing clinical problem.

BACKGROUND: Group B beta-hemolytic streptococcus (Streptococcus agalactiae) has been traditionally considered a major pathogen in neonates and pregnant women. However, there is accumulating concern about its significance in non-pregnant adults too. MATERIAL/METHODS: To study Streptococcus agalactiae infections in non-pregnant adults in a 354-bed general tertiary center in Athens, Greece, we analyzed retrospectively collected data from patients with Streptococcus agalactiae isolates during a 5-year period. RESULTS: Sixty-nine strains were isolated from specimens of 65 non-pregnant adults (42 women and 23 men). Thirty-four of them were managed as inpatients and 31 as outpatients. Mean age of the 34 inpatients was 57.7 (range 18-84) years. Nineteen (17 women and 2 men) of the 34 inpatients had the organism isolated from urine. Thirteen of these 19 (68.4%) patients had clinical evidence of urinary tract infection (UTI). Streptococcus agalactiae infections were diagnosed in 26 of 34 inpatients. Besides the 13 inpatients with an UTI, 2 had bacteremia of unknown origin, 2 pneumonia, 2 erysipelas, 1 spondylodiscitis, 1 peritonitis, 2 prostatitis, 1 perirectal abscess, 1 testicular abscess, and 1 diabetic foot infection. Underlying conditions of the 26 inpatients possibly predisposing to infections were neoplasia, diabetes mellitus, heart disease, splenectomy, and corticosteroid treatment. CONCLUSIONS: In keeping with results from other recent studies Streptococcus agalactiae was isolated more frequently than previously believed from non-pregnant adults in our study. In addition, our data suggest that Streptococcus agalactiae may be an underestimated cause of UTI in non-pregnant women.

Adolescent↗
PubMed2004

Streptococcus sinensis may react with Lancefield group F antiserum.

Lancefield group F streptococci have been found almost exclusively as members of the 'Streptococcus milleri' group, although they have been reported very occasionally in some other streptococcal species. Among 302 patients with bacteraemia caused by viridans streptococci over a 6-year period, three cases were caused by Streptococcus sinensis (type strain HKU4T, HKU5 and HKU6). All three patients had infective endocarditis complicating their underlying chronic rheumatic heart diseases. Gene sequencing showed no base differences between the 16S rRNA gene sequences of HKU5 and HKU6 and that of HKU4T. All three strains were Gram-positive, non-spore-forming cocci arranged in chains. All grew on sheep blood agar as alpha-haemolytic, grey colonies of 0.5-1 mm in diameter after 24 h incubation at 37 degrees C in ambient air. Lancefield grouping revealed that HKU5 and HKU6 were Lancefield group F, but HKU4T was non-groupable with Lancefield groups A, B, C, D, F or G antisera. HKU4T was identified by the Vitek system (GPI), API system (20 STREP) and ATB system (ID32 STREP) as 99 % Streptococcus intermedius, 51.3 % S. intermedius and 99.9 % Streptococcus anginosus, respectively. Using the same tests, HKU5 was identified as 87 % Streptococcus sanguinis/Streptococcus gordonii, 59 % Streptococcus salivarius and 99.6 % S. anginosus, respectively, and HKU6 as 87 % S. sanguinis/S. gordonii, 77 % Streptococcus pneumoniae and 98.3 % S. anginosus, respectively. The present data revealed that a proportion of Lancefield group F streptococci could be S. sinensis. Lancefield group F streptococci should not be automatically reported as 'S. milleri'.

Bacteremia↗
PubMed2001

In vitro activity of gemifloxacin (SB-265805) compared to eleven other antimicrobial agents against streptococcal isolates, excluding Streptococcus pneumoniae.

The purpose of the study presented here was to determine the in vitro activity of gemifloxacin compared with that of 11 other antimicrobial agents (5 of them quinolones) against 400 isolates of beta-haemolytic and viridans group streptococci. The minimum inhibitory concentration values for gemifloxacin against 90% of the streptococci tested were as follows: Lancefield groups A, C and G, 0.06 microg/ml; Lancefield group B, Streptococcus mitis, Streptococcus mutans and Streptococcus bovis, 0.125 microg/ml; and Streptococcus milleri, 0.03 microg/ml. Resistance to penicillin, ampicillin and erythromycin was found mainly in the Streptococcus mitis isolates; tetracycline showed variable results, and no vancomycin resistance was encountered. Higher rates of ciprofloxacin resistance were identified in the Streptococcus bovis, mitis and mutans isolates. In conclusion, gemifloxacin was the most active quinolone tested followed by trovafloxacin, sparfloxacin, grepafloxacin, ciprofloxacin and levofloxacin, especially against isolates resistant to beta-lactam agents, macrolides and tetracycline.

Anti-Bacterial Agents↗
PubMed2003

Bacteremic pneumococcal cellulitis compared with bacteremic cellulitis caused by Staphylococcus aureus and Streptococcus pyogenes.

In order to better characterize bacteremic cellulitis caused by Streptococcus pneumoniae, a review was conducted of 10 cases of bacteremic pneumococcal cellulitis, which represented 0.9% of all cases of pneumococcal bacteremia (n=1,076) and 3.2% of all cases of community-acquired bacteremic cellulitis (n=312) that occurred in the Hospital de Bellvitge, Barcelona, from 1984 to 2001. In addition to these 10 cases, 28 cases of bacteremic pneumococcal cellulitis from the literature (Medline 1975-2001) were reviewed. Pneumococcal cellulitis of the face, neck, and trunk was observed more frequently in patients with systemic lupus erythematosus and hematologic disorders, while pneumococcal cellulitis of the limbs was more common in patients with diabetes, alcoholism, and parenteral drug use. In the Hospital de Bellvitge group, bacteremic cellulitis due to Streptococcus pneumoniae was more frequently associated with severe underlying diseases than that due to Staphylococcus aureus or Streptococcus pyogenes (100%, 57%, and 72%, respectively;P=0.01). A concomitant extracutaneous focus of infection (e.g., respiratory tract infection) suggesting hematogenous spread with metastatic cellulitis was more frequent in patients with pneumococcal cellulitis, while a local cutaneous entry of microorganisms was feasible in most patients with Staphylococcus aureus or Streptococcus pyogenes cellulitis. The 30-day mortality was 10% in patients with pneumococcal cellulitis, 13% in patients with Staphylococcus aureus cellulitis, and 23% in patients with Streptococcus pyogenes cellulitis (P=0.3). Thus, bacteremic pneumococcal cellulitis is an unusual manifestation of pneumococcal disease and occurs mainly in patients with severe underlying diseases. In most cases, pneumococcal cellulitis has a different pathophysiologic mechanism than cellulitis caused by Staphylococcus aureus or Streptococcus pyogenes.

Adult↗
PubMed1998

Reversed-phase high-performance liquid chromatographic measurement of the P-aminobenzoic acid synthesized by Streptococcus sanguis.

OBJECTIVE: This study investigated the biosynthesis of P-aminobenzoic acid by Streptococcus sanguis and the role of P-aminobenzoic acid in the interaction between Streptococcus sanguis and Streptococcus mutans. METHODS: A reversed-phase high-performance liquid chromatographic technique was used to analyze the P-aminobenzoic acid synthesized by Streptococcus sanguis in an anaerobic atmosphere. RESULTS: The results showed, that (1) the chromatographic method established in this study had good linear relation and the average recovery of P-aminobenzoic acid was 80%, and (2) Streptococcus sanguis did synthesize P-aminobenzoic acid, and the mean concentration of P-aminobenzoic acid was 1.23 micrograms/mL. CONCLUSIONS: The results of this study will help further studies of the factors that may have effects on P-aminobenzoic acid synthesis by Streptococcus sanguis and on the role of P-aminobenzoic acid in the microbial homeostasis of dental plaque.

4-Aminobenzoic Acid↗
PubMed1977

Biological characteristics of peptidoglycans of group A streptococcus and some other bacterial species. I. Tolerance and effect of antibody in fever response, and heart damaging effect in rabbits.

Induced tolerance to the pyrogenic action of group A streptococcus peptidoglycan decreased after one week and was no longer detectable after the second week. However, one or two further doses of peptidoglycan rapidly restored the tolerance. The passive transfer of plasma from rabbits tolerant to streptococcus peptidoglycan to nontolerant animals failed to transfer tolerance. Antiserum to streptococcus peptidoglycan neutralized the pyrogenic effect of not only streptococcus but also staphylococcus and pneumococcus peptidoglycan; it did not influence the febrile response to endotoxin. Histopathologic changes in the rabbit heart produced by the intravenous injection of staphylococcus or pneumococcus peptidoglycans were similar and were characterized by various stages of degeneration and necrosis. The changes were less pronounced than after streptococcus peptidoglycan. Antiserum to streptococcus peptidoglycan had modest or no counteracting effect on the development of heart alterations after staphylococcus or pneumococcus peptidoglycan.

Animals↗
PubMed1978

Biological characteristics of peptidoglycans of group A streptococcus and some other bacterial species. II. Immunological mechanisms involved in thrombocytolysis.

Immunological mechanisms are involved in the thrombocytolytic activity of peptidoglycan of Group A streptococcus, Streptococcus pneumoniae and Staphylococcus aureus. Inactivation of particular components of complement (heating of blood serum to 56 degrees C,incubation with zymosan or NH4OH) inhibited the thrombocytolytic activity of group A streptococcus peptidoglycan. So did preincubation of Group A streptococcus peptidoglycan with homologous antipeptidoglycan antibody. On the other hand, antibody to Group A streptococcus peptidoglycan did not inhibit the thrombocytolytic effect of Streptococcus pneumoniae or Staphylococcus aureus peptidoglycan. Human platelets are resistant to peptidoglycans. They remain resistant in the presence of rabbit serum although rabbit platelets are highly sensitive to peptidoglycans. This suggests that, for the expression of the thrombocytolytic activity of bacterial peptidoglycan, specific receptors on the surface of platelets must be present in addition to serum factors.

Animals↗
PubMed1984

Primary plate identification of group A Streptococcus on a selective medium. Efficiency in an office practice.

The efficiency of group A Streptococcus detection and identification in an office practice was studied using a selective blood agar plate containing sulfamethoxazole and trimethoprim and primary plate bacitracin disk speciation. All results were confirmed by conventional bacteriologic and immunologic techniques the next day by a reference laboratory. In all, 1,591 cultures were processed, of which 156 (10%) could be confirmed the next morning to have group A Streptococcus by primary disk susceptibility interpretation. Bacitracin-resistant beta-hemolytic colonies, which could be immunologically confirmed as group A Streptococcus grew from only three cultures (0.1%). Fifty-six (3%) of the cultures had too few beta-hemolytic colonies to determine bacitracin susceptibility, of which 47 were later proved to be group A Streptococcus. On all preliminary negative cultures, 1% demonstrated group A Streptococcus after incubation for an additional 24 hours. If a selective blood agar plate with primary bacitracin disk susceptibility speciation is used in an office laboratory setting, 99% of all cultures can be accurately interpreted within 24 hours of incubation, providing that those plates with limited growth of beta-hemolytic colonies are thereafter immunologically tested for group A Streptococcus antigen.

Agar↗
PubMed1996

Cloning, sequencing and expression of the CAMP factor gene of Streptococcus uberis.

The gene coding for the CAMP factor from a strain of Streptococcus uberis (ATCC 9927) was cloned in Escherichia coli. Chromosomal DNA from Streptococcus uberis was used to construct a gene library in plasmid pTZ18R and six CAMP-reaction positive clones were obtained from a total of 10,000 transformants. One clone, pJLD21, was subcloned and the CAMP factor gene was located in a 3.2 kb BamHI fragment. The nucleotide sequence of Streptococcus uberis CAMP factor gene was determined and the deduced amino acid sequence is highly homologous to the corresponding Streptococcus agalactiae protein. Immunoblot analysis revealed that the recombinant strain pJLD21 expressed a protein with a molecular weight of 28 000. Antibodies raised against purified Streptococcus uberis CAMP factor cross-reacted with Streptococcus agalactiae protein B.

Amino Acid Sequence↗
PubMed1996

Seven-year review of bacteremia caused by Streptococcus milleri and other viridans streptococci.

The Streptococcus milleri group is associated with a spectrum of serious suppurative infections that have not been well defined. The purposes of this study were to ascertain the clinical significance of Streptococcus milleri bacteremia and to determine the epidemiological, clinical, and microbiological features of these infections compared to those caused by other viridans streptococci. All cases of streptococcal bacteremia observed in a Spanish hospital in the period from January 1988 to December 1994 were reviewed. Of 137 cases of Streptococcus milleri infection, 33 (24%) were documented cases of bacteremia. Twenty-four patients were men (mean age 57.8 +/- 17.4 years). The majority of infections were abdominal in origin (20/33), the most frequent diagnoses being cholangitis/cholecystitis (18%) and appendicitis (12%). The origin of infection could not be established in three cases. Nine cases of bacteremia (27%) were polymicrobial. Six patients (18%) had septic shock; in four the infection was polymicrobial, and in two the infection was of abdominal origin. Eighteen of the 33 patients (54%) required surgery. Five patients died. All 33 Streptococcus milleri isolates were susceptible to penicillin. Twenty-two cases of bacteremia caused by other viridans streptococci were observed during the same period. There were no statistically significant differences between the two groups in terms of age, sex, mortality, rate of polymicrobial infection, rate of nosocomial acquisition of bacteremia, or the occurrence of shock. An abdominal origin of infection was more frequent in Streptococcus milleri bacteremia (p = 0.0001); a cardiovascular origin was more frequent in the viridans group (p = 0.01), as was a diagnosis of endocarditis (p = 0.004). Four patients with viridans streptococci bacteremia required surgery versus 18 patients with Streptococcus milleri bacteremia (p = 0.01). Viridans streptococci were notably less susceptible to penicillin (89%), clindamycin (79%), and erythromycin (79%).

Adolescent↗
PubMed1996

Sexual behavior and vaginal colonization by group B streptococcus among minority women.

OBJECTIVE: To test the hypothesis that sexual behaviors predict colonization of the vagina by group B streptococcus among minority women. METHODS: We conducted a prospective, descriptive study of 192 consecutive African-American (37%) and Hispanic women (63%). Each woman underwent a detailed interview concerning sexual behavior. Separate specimens were taken from the endocervix, upper vagina, lower vagina, and anorectum and placed in selective broth media for isolation of group B streptococcus. Significant behavioral predictors of vaginal group B streptococcus colonization and heavy (3-4+) colonization were identified using stepwise logistic regression. RESULTS: The incidence of vaginal colonization was 39% and heavy colonization was 35%. Nineteen percent reported anal intercourse, 46% reported sex at least two times per week, and 21% reported more than one partner in the previous 30 days. The significant predictors of vaginal group B streptococcal infection were: African-American ethnicity, adjusted odds ratio (OR) 6.1 (95% confidence interval [CI] 2.5-15.1); presence of rectal group B streptococcus, adjusted OR 100.6 (95% CI 26.7-379.3); nulliparous, adjusted OR 3.6 (95% CI 1.4-9.5); and nonpregnant status, adjusted OR 3.9 (95% CI 1.3-12.2). The significant predictors of heavy colonization were: more than one partner in the last 30 days, adjusted OR 2.6 (95% CI 1.2-5.6); and African-American ethnicity, adjusted OR 2.3 (95% CI 1.2-4.5). Anal intercourse was associated with a reduced likelihood of vaginal group B streptococcal infection, adjusted OR 0.34 (95% CI 0.12-0.91). CONCLUSION: Sexual behavior, especially anal intercourse, does not predict vaginal colonization by group B streptococcus. African-American women are more likely to have vaginal and heavy group B streptococcus colonization. Heavy vaginal colonization is associated with multiple partners in African-American women.

Adult↗
PubMed1986

Balanitis caused by group B streptococcus.

The Lancefield group B streptococcus is a cause of serious genitourinary tract infections in peripartum women. However, it rarely has been implicated as a pathogen in genital infections of male subjects. We report severe recurrent balanitis owing to group B streptococcus in a sexually active young man. Group B streptococcus was cultured from the vagina of his asymptomatic consort on 1 occasion. It is postulated that penile cellulitis developed by invasion of group B streptococcus through a traumatic abrasion acquired during sexual intercourse. The preferred antibiotic treatment for balanitis caused by group B streptococcus is penicillin or erythromycin. Prevention of additional episodes may be difficult, since therapy of the female carrier state with antibiotics has not provided long-term eradication of group B streptococcus.

Adult↗
PubMed1999

Group B streptococcus infection rate unchanged by gestational diabetes.

OBJECTIVE: Group B streptococcal colonization in pregnancy has been associated with adverse perinatal outcomes, including intra-amniotic infection, postpartum endometritis, and neonatal sepsis. We sought to determine whether gestational diabetes increases the risk of maternal and neonatal morbidity from group B streptococcal colonization. METHODS: Gestational diabetic and nondiabetic women who underwent vaginal or anogenital culture for group B streptococcus colonization in pregnancy were followed up for pregnancy outcome. Antibiotic prophylaxis was not routinely given. Major perinatal morbidity included intraamniotic infection, endometritis, and neonatal sepsis. Potential confounding variables included induction of labor, cesarean delivery, prematurity, maternal antibiotic use, and prolonged rupture of membranes. RESULTS: We compared 446 gestational diabetic women to 1,046 nondiabetic women for outcome. Overall, 12% were colonized with group B streptococcus, with no difference in colonization rates between gestational diabetic (12%) and nondiabetic (12%) women. There were no differences in intraamniotic infection rates between gestational diabetic and nondiabetic women, whether group B streptococcus positive (16% compared with 13%) or group B streptococcus negative (10% compared with 11%). Likewise, endometritis did not differ (6-9%) regardless of diabetes or group B streptococcus status. Neonatal sepsis was higher in group B streptococcus-positive women overall (3% compared with 1%, odds ratio 3.71, 95% confidence interval 1.23, 10.81), but did not differ between diabetic and nondiabetic pregnancies. CONCLUSION: Gestational diabetes does not alter the perinatal morbidity associated with group B streptococcal colonization in pregnancy.

Adult↗
PubMed2000

Characterization of acid phosphatase activities in the equine pathogen Streptococcus equi.

Acid phosphatases hydrolyse phosphomonoesters at acidic pH in a variety of physiological contexts. The recently defined class C family of acid phosphatases includes the 32 kDa LppC lipoprotein of Streptococcus equisimilis. To define further the distribution of acid phosphatases in the genus Streptococcus we have examined the equine pathogens Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus. Whole cell assays indicated that these organisms possess two acid phosphatases with activity optima at pH 5.0 and pH 6.0-6.5 and that only the former of these was, like LppC, resistant to EDTA. Western blotting with a polyclonal anti-LppC antiserum revealed the presence of a cross-reactive 32 kDa protein in both organisms. The cross-reactive protein in S. equi was shown to be a surface accessible lipoprotein as its processing was inhibited by the antibiotic globomycin and it was released from whole cells by treatment with trypsin. The presence of DNA sequences homologous to the S. equisimilis lppC gene were confirmed by PCR. These data strongly suggest that Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus produce a lipoprotein acid phosphatase homologous to LppC of S. equisimilis.

Acid Phosphatase↗
PubMed2001

Prevalence and phenotypes of erythromycin-resistant Streptococcus pneumoniae in Shanghai, China.

Bacterial resistance of Streptococcus pneumoniae against erythromycin and clindamycin and resistance phenotypes of erythromycin-resistant Streptococcus pneumoniae were investigated. The MICs of erythromycin and clindamycin against 345 strains of Streptococcus pneumoniae were tested with agar dilution method; the phenotypes of erythromycin-resistant Streptococcus pneumoniae were detected by double-disk test. One hundred and eighty-three and 171 of 345 (53.0% and 49.6%) of isolates had MICs > or =1 microg/ml for erythromycin and for clindamycin. Among erythromycin-resistant Streptococcus pneumoniae, the percentage of cMLS, iMLS and M phenotype was 90.3% (159/176), 5.7% (10/176) and 4.0% (7/176), respectively. The incidence of erythromycin-resistant Streptococcus pneumoniae is very high in Shanghai. The main phenotype is cMLS.

Child↗
PubMed1992

Etiology and antibiotic susceptibility of bloodstream Streptococcus sp.

249 episodes of Streptococcus bacteraemia in hospitalized patients were evaluated for both clinical and microbiological features. Specification of the isolates demonstrated that infective endocarditis was predominantly associated with Streptococcus sanguis and Streptococcus bovis whereas Streptococcus pyogenes and Streptococcus milleri were the most common cause of local and/or systemic infections. In vitro-susceptibility tests towards 9 selected antibiotics proved that beta-lactam antibiotics are potent compounds for the treatment of Streptococcus sp. with the exception of enterococci; that ampicillin turned out to be highly effective against enterococci; and that vancomycin may be regarded as a potent alternative in the treatment of streptococcal infections.

Anti-Bacterial Agents↗
PubMed1975

Evaluation of human oral organisms and pathogenic Streptococcus for production of IgA protease.

IgA protease is a proteolytic enzyme found in whole human saliva and in dental plaque that cleaves both secretory and myeloma IgA of human origin to yield intact Fabalpha and Fcalpha fragments. To determine which bacteria are capable of producing this enzyme, we have examined a variety of strains normally found in the human oral cavity and a number of streptococci of known Lancefield group serotype. Streptococci of groups A, B, C, D, F, G, H, M, and N, Streptococcus mutans, Streptococcus sanguis, Streptococcus mitior, Streptococcus salivarius, Streptococcus faecalis, Veillonella, Lactobacillus, Actinomyces, Propionibacterium, Bacteroides, and Fusobacterium were grown in liquid medium, and fluids were examined for IgA protease activity. Only S. sanguis and clinically isolated group H streptococci elaborated IgA protease under the culture conditions used. Negative strains could not be stimulated to produce the enzyme when cultured in the presence of secretory IgA. Among the natural oral bacteria, capacity to produce IgA protease is restricted to certain species of Streptococcus, notably those of the group H serotype. Since secretory immunity is mediated by the IgA class of antibody, the presence of this enzyme at mucosal surfaces could modify the secretory immune function.

Actinomyces↗