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PubMed1997

Serotyping of Streptococcus pyogenes isolated from common and severe invasive infections in Japan, 1990-5: implication of the T3 serotype strain-expansion in TSLS. The Working Group for Group A Streptococci in Japan.

To clarify the relationship between the epidemics of severe invasive group A streptococcal infections (streptococcal Toxic Shock-Like Syndrome: TSLS) and common group A streptococcal infections in Japan, we examined the T serotypes of S. pyogenes strains (group A streptococci) isolated from clinical specimens of the streptococcal infections (17999 cases) in the period 1990-5, including the severe infections (TSLS) (29 cases) in the period 1992-5. Characteristic points of the analyses were: (1) dominant serotypes of the infections in these periods were T12, T4, T1, T28 and TB3264, which were consistently isolated; (2) isolates of T3 rapidly increased through 1990 to 1994 while T6 decreased in the period 1990-3; (3) when Japanese area was divided into three parts, T3 serotype tended to spread out from the north-eastern to the south-western area; (4) strains of T3 and T1 serotypes were dominant in the TSLS. Dominant-serotype strains of streptococcal infections did not always induce severe infections and dominance of T3 serotype in the TSLS seemed to be correlated with the increase of T3 in streptococcal infections. These results may indicate that certain clones of S. pyogenes are involved in the pathogenesis of the TSLS.

Adolescent↗
PubMed1969

Effect of pH on in vitro phagocytosis of Streptococcus pyogenes.

Phagocytosis experiments were performed with mouse peritoneal leucocytes (MPL). The natural pH of the mouse peritoneal cavity was found to be between 6.1 and 6.3. The phagocytic and intracellular killing activities of MPL by pH variations was studied. It was observed that the optimal ingestion and intracellular killing of bacteria is at the natural pH of the peritoneal cavity.

Animals↗
PubMed1981

Localisation of 125I-labelled streptolysin O of Streptococcus pyogenes in mice.

The fate of 125I-labelled Streptolysin O injected intravenously into mice was studied. After 2 hours only 5% of the injected label remained in the blood. The highest concentration of radioactivity was consistently observed in the liver and kidneys. The labelled toxin was degraded in the liver but its greatest toxic effect took place in the kidneys.

Animals↗
PubMedDate not supplied

[Determination of the bactericidal potency of cefatrizine and other oral antibiotics against Haemophilus influenzae, Klebsiella pneumoniae and Streptococcus pyogenes].

The in vitro determination of the T log and the minimal bactericidal time of cefatrizine was evaluated against H. influenzae, Str. pyogenes A isolated from clinical specimens. and K. pneumonia ATCC 10031 and compared with that of amoxycillin, cefaclor, cefroxadine and miocamycin against the same bacterial strains. Cefatrizine demonstrate the shorter TMB against all bacterial strains and antibiotic tested with MBCs.

Administration, Oral↗
PubMed1995

Insertional inactivation of virR in Streptococcus pyogenes M49 demonstrates that VirR functions as a positive regulator of streptococcal C5a peptidase and M protein in OF+ strains.

Mutational analysis confirms the presence of a positively controlled virulence regulon in the OF+ lineage of S. pyogenes. Although there are differences in the organization of the virR regulon in OF+ and OF- strains, expression of these surface proteins is dependent on a VirR protein. In addition, it appears that production of OF is dependent on virR. The contribution of OF to the pathogenesis of S. pyogenes is unknown. The greater association of OF+ strains with impetigo compared to the greater association of OF- strains with pharyngitis [2] may indicate that production of apoproteinase is a contributing factor to skin infections.

Adhesins, Bacterial↗
PubMed1976

Comparison of the agglutination and the co-agglutination techniques in T-tying of Streptococcus pyogenes.

A comparison of two different methods in T-typing 200 Norwegian group A strains is reported. The traditional agglutination technique was compared with the co-agglutination method of Christensen and co-workers. Fifty-five strains could not be typed by either method. The typing results for 128 of the strains were in agreement. The most common T types were the folloiwng: 1, 4, 8, 12, 13, 28, and strains belonging to the T pattern 5/11/12/27/44.

Agglutination Tests↗
PubMed1989

Possible role of Streptococcus pyogenes in mucocutaneous lymph node syndrome. IX. Quantitation by ELISA of streptococcal pyrogenic exotoxin in the serum of MCLS patients.

In the present paper we describe the use of an enzyme-linked immunosorbent assay reinforced with an introduction of monoclonal antibody, for the detection and quantitation of streptococcal pyrogenic exotoxin (SPE) in the serum of patients with mucocutaneous lymph node syndrome (MCLS). The amount of SPE was usually at a high level, and its 100% incidence in patients' sera was proved whenever the assay was made on the day of admission, thereby showing a marked contrast to carefully matched control sera which failed to mediate any positive result. As for the change in detected amount of the toxin, a clear dichotomy was observed between the serum of gammaglobulin-treated patients and that of infants given aspirin; in the former the positive result turned to negative rapidly following the initiation of treatment coupled with a defervescence, while in the latter the reduction of SPE levels was scarcely monitored for as long as 17 days after the onset of illness. Quantitation of SPE might be an auxiliary test for the diagnosis of MCLS, because a considerable amount of SPE was assessed in a patient who developed characteristic huge coronary artery aneurysms following an illness which did not fulfill the diagnostic criteria. These findings support our speculation in relation to the certain role of S. pyogenes as an etiological agent for MCLS. The possible mechanisms of gammaglobulin treatment in reducing the prevalence of cardiovascular lesions and the duration of systemic inflammation are discussed.

Animals↗
PubMedDate not supplied

[The phage sensitivity and lysogeny of cultures of Streptococcus pyogenes group A isolated in different streptococcal infections].

The collection of moderate phages of S. pyogenes, group A, had been created earlier. As shown in this work, group A streptococcal cultures isolated from patients with rheumatism, glomerulonephritis and tonsillitis exhibited different sensitivity to the phages of this collection: the cultures were lyzed by phages of groups II and III in rheumatism, group III in tonsillitis and group I in glomerulonephritis. The study revealed that lysogeny was widely spread among S. pyogenes strains isolated from patients with different diseases under study. Most frequently occurred among cultures isolated from tonsillitis patients. In this disease only phage-resistant streptococcal cultures proved to be lysogenic. Lysogeny was found among both phage-sensitive and phage-resistant cultures in rheumatism and especially in glomerulonephritis.

Bacteriophage Typing↗
PubMed2000

[An outbreak of scarlet fever, impetigo and pharyngitis caused by the same Streptococcus pyogenes type T4M4 in a primary school].

UNLABELLED: EPIDEMIC: Following the notification of an unusual number of scarlet fever cases within the same primary school, the epidemiological and clinical features of the outbreak were investigated. Questionnaire information about the cases was collected from parents and general practitioners per telephone. Throat specimens were taken, before and after treatment, for culturing and specific typing of streptococci was performed to determine transmission. Within a period of one month, 21 schoolchildren in a class of 29 pupils, with a mean age of 5 years, presented with symptoms caused by streptococcal infection (attack rate: 72%). Eight had scarlet fever, 5 suffered from impetigo and 8 had pharyngitis. A further 6 children, outside of this class, had complaints of scarlet fever, impetigo or pharyngitis. For 90% (26/29) of the schoolchildren a throat culture was established. Twelve positive cultures of the same strain of beta-haemolytic group A streptococcus, T4M4 exotoxin C gene positive, were found. The advice given was to treat all positive children for 3 days with azithromycin to prevent complications and further spreading of the disease. After two weeks only one child, that had not taken the antibiotics, still had a positive throat culture. No further cases or complications were reported. DISCUSSION: The pattern of the outbreak was typical of a person-to-person transmission. This was confirmed by typing of the isolates. The results of this study demonstrate the importance of mandatory notification of infectious clusters by institutions, such as schools, as introduced in the new Dutch Infectious Disease Act. On the one hand, the notification gives the municipal health authority the opportunity to analyse source and transmission dynamics and on the other to prevent disease and complications.

Bacterial Typing Techniques↗
PubMed1979

The role of M protein in phagocytosis. II. Opsonization of Streptococcus pyogenes in vitro.

Opsonization of two different streptococcal group A type 12 strains was investigated. The strains differed only in M protein presence. It was observed that after the treatment of bacteria with fresh normal rabbit serum M positive strains bind to their surface IgG only whereas M negative strains solely some complement components. These results may suggest that streptococci lacking M protein are able to activate complement by alternate pathway.

Animals↗
PubMed1987

[Changes in the cell wall composition and structure of Streptococcus pyogenes during batch culture].

Changes in S. pyogenes cells in the process of batch cultivation have been studied. The composition of S. pyogenes cell walls has been studied by amino acid analysis; besides, their resistance to enzymatic hydrolysis and the electric conductivity of cell-wall lysates have been determined at different phases of the growth of S. pyogenes. The molar amino acid composition, expressed in percent, is unrelated to the growth phase, while the content of amino acids in preparations changes in the process of growth and reaches its maximum in the middle and in the end of the logarithmic phase. At the same time the electric conductivity of cell-wall lysates reaches the minimum level at these growth stages. The authors suggest that additional electrically charged compositions are formed in the cell walls at the beginning of the logarithmic and stationary phases. A considerable increase in the initial rate of cell-wall lysis with muramidase has been found to occur at the end of the logarithmic phase. This difference in the initial rate in the initial rates of lysis of S. pyogenes cell walls at different growth phases decreases after previous treatment of the cell walls with streptolytin possessing proteolytic activity. Analysis of these data leads to a conclusion on the "loose" structure of the outer protein layer of the cell wall at the end of the logarithmic phase of the growth curve.

Amino Acids↗
PubMed2005

Rapid inversion of the prevalences of macrolide resistance phenotypes paralleled by a diversification of T and emm types among Streptococcus pyogenes in Portugal.

In Portugal erythromycin resistance of 26.6% (n = 352) remained constant during 1998 to 2003, however in 1998 the MLS(B) phenotype dominated (85%), whereas in 2003 the M phenotype prevailed (77%). A decline in T12/emm22 MLS(B) isolates could partially explain the drop in this phenotype, but the rise of the M phenotype was not due to clonal expansion.

Anti-Bacterial Agents↗
PubMed1978

Chemotactic activity of polymorphonuclear leukocytes to Streptococcus pyogenes.

Influence of two different streptococcal group A type 12 strains on chemotactic activity of polymorphonuclear leukocytes (PMN) was investigated in vitro and in vivo. The strains differed only in presence of M protein. In both conditions, the inhibition of the chemotaxis of the PMN after their treatment with M positive strains was observed. These results suggest that M protein of streptococci inhibits chemotaxis of PMN and therefore they can weaken defensive mechanisms of infected organism.

Animals↗
PubMed1995

Intracellular penetration and survival of Streptococcus pyogenes in respiratory epithelial cells in vitro.

Recurrence of pharyngotonsillitis caused by S. pyogenes after seemingly adequate antibiotic treatment has puzzled scientists for many years. We investigated the ability of S. pyogenes to invade HEp-2 cells and survive intracellularly. Five strains were tested, of which two were isolated from patients with recurrent pharyngotonsillitis, two without recurrent infection, while one was a reference strain. All five strains were found capable of penetrating the cells and surviving intracellularly for between 4 and 7 days. In this manner, an intracellular reservoir of bacteria was created, with the potential to cause recurrent infections.

Cells, Cultured↗
PubMed2002

In vitro bactericidal activity of ABT-773 and amoxicillin against erythromycin-susceptible and -resistant strains of Streptococcus pyogenes.

The bactericidal activity of ABT-773 was compared with amoxicillin against 10 clinical isolates of S. pyogenes (six erythromycin susceptible and four erythromycin resistant). The MIC ranges (mg/L) were 0.004-0.25 of ABT-773 and 0.015-0.12 of amoxicillin. At 24 h, ABT-773 concentrations of 2 x MIC and 8 x MIC were bactericidal against three and six organisms, respectively. In comparison, amoxicillin was bactericidal against all 10 organisms at both test concentrations.

Amoxicillin↗