Role Of Streptococcus Pyogenes Research Articles

Unusual case of Lemierre s Syndrome in a 5 year old

Streptococcus pyogenes is a common cause of invasive infections. The role of Streptococcus pyogenes in the combination of meningitis and Lemierre’s syndrome is rare.

Bacteriology of the Tonsil Core in Recurrent Tonsillitis and Tonsillar Hyperplasia - a Short Review

In recurrent tonsillitis, the tonsil core harbours numerous bacteria, some of which are pathogenic and may occur in great numbers. The most frequent bacteria are Haemophilus influenzae , followed by Staphylococcus aureus and Streptococcus pyogenes . A high tissue concentration of these bacteria correlates with clinical parameters of infection and hyperplasia of the tonsils. The role of Streptococcus pyogenes , while undisputed in acute and epidemic tonsillitis, should perhaps be re-evaluated in recurrent and/or hyperplastic tonsillitis.

Role of Streptococcus pyogenes in the etiology of Erysipelas.

The suggestion that erysipelas is caused by special streptococcal toxin has been substantiated. The current nature of disease suggests that it may be a hypersensitivity reaction to streptococcal products1. The aim of this work is to prove, if any, the role of Streptococcus pyogenes in the etiology of erysipelas.

Streptococcus pyogenes: resistant, tolerant, neither or both?

The role of Streptococcus pyogenes in pharyngitis as well as its importance in the sequelae of that infection is well known and a constant concern. However, in the last several years, the number of life-threatening infections caused by S. pyogenes, such as toxic shock-like syndrome and severe invasive disease, have increased the concern about this organism.1,2,3

Neonatal shock

This review discusses the literature on neonatal shock published in 1993. Etiologies for shock including the role of enterotoxins in sudden infant death syndrome and the role of Streptococcus pyogenes in streptococcal toxic shock syndrome are discussed. The monitoring of cardiac function, oxygen consumption, and oxygen delivery in neonates with shock and in children after cardiac surgery are discussed. The physiology of shock including the metabolic and cytokine mediator responses to shock are outlined, and the various new treatment modalities are compared. These include conventional inotropic therapy, extracorporeal membrane oxygenation, and cytokine manipulation.

Probable role of Streptococcus pyogenes in Kawasaki disease.

Over the past 25 years, the clinical course of Kawasaki disease has been defined, the prevalence and nature of the cardiovascular effects widely understood, and pathological changes in the most severe cases well described. However, the aetiology and pathogenesis of this puzzling disease have remained unclear, thus specific therapy is not yet available. Because of some close clinical similarities between this disease and streptococcal scarlet fever, particular attention has been paid to the possible role of Streptococcus pyogenes as an aetiological agent in this illness. Until now, however, group A beta-haemolytic streptococci have never been consistently isolated from any patients; in addition, the titre of anti-streptolysin 0 is not raised, and lack of response to antibiotics is a feature of this disease. Our long series of investigations over more than 10 years, which will be covered in the present review, were performed in an attempt at elucidating causative agent(s) of Kawasaki disease. This has led to our firm belief in the probable role of S. pyogenes in the pathogenesis of this disease, despite the lack of fulfillment of Koch's postulates, on the basis of the following findings. Patients with Kawasaki disease recovering from the acute, febrile phase of the illness exhibited an exaggerated cell-mediated reactivity, as measured by the macrophage migration inhibition test, to group A beta-haemolytic streptococci, their pyrogenic exotoxin and streptolysin 0 as well as to several mammalian muscle cell extracts which are allegedly related antigenically to the cell wall and/or cytoplasmic membrane of S. pyogenes. Protoplast-like "spherical bodies" varying in diameter from 0.5 to 1.5 microns, and devoid of cell walls, were detected in the buffy coats of peripheral blood from patients with this disease, and stained distinctly by immuno-electron microscopy using, as a primary antibody, a rabbit antiserum to S. pyogenes- derived protoplasts, and followed by absorption with protoplasts from Staphylococcus aureus and Escherichia coli. Newborn mice infected with S. pyogenes having no capacity to confer cell-mediated immunity even in adult murine hosts, and reinfected 4-6 weeks later with another strain of the same species of bacteria which is able to elicit cellular immunity, showed a lack of humoral response to streptococcal antigens, leaving intact cell-mediated immunity. Such a biased immunological characteristic is an exact counterpart of that of Kawasaki disease patients.(ABSTRACT TRUNCATED AT 400 WORDS)

Possible role of Streptococcus pyogenes in mucocutaneous lymph node syndrome. XV. Potential utility of streptococcal pyrogenic exotoxin toxoid for the prophylaxis and treatment of MCLS.

Mice made tolerant to streptococcal pyrogenic exotoxin (SPE) by neonatal inoculation with SPE emulsified in incomplete Freund's adjuvant demonstrated early thrombocytopenia followed by thrombocytosis. This state is the perfect counterpart of patients with mucocutaneous lymph node syndrome (MCLS). We have hypothesized that by inducing tolerance to SPE, the biological activities of the toxin might play leading roles in the pathogenesis of MCLS. In the present investigations, the efficacy of SPE on the prophylaxis and treatment of diseases caused by Streptococcus pyogenes (including MCLS) were monitored using the murine model system accompanied with a platelet-counting technique. The mice, rendered tolerant due to neonatal SPE inoculation and followed by immunization with SPE toxoid about 1 month prior to the provocative injections with SPE, demonstrated an almost complete lack of response to the provocation, keeping platelet counts within the normal range of values (except for a marginally significant thrombocytosis 7 days postprovocation). Moreover, anti-SPE titers of the sera from the mice sacrificed on day 35, at which point the observation was terminated, were proved to be markedly elevated when compared with controls. These findings seem to suggest that immunization with the toxoid could overcome tolerance, resulting in the production of an antitoxin. In a second experiment that examined the effect of administration with rabbit antiserum raised against the toxoid, the antiserum-treated mice demonstrated a transitory thrombocytosis on 7 days postprovocation with SPE, followed by an abrupt decrease in the number of platelets from day 10 onward.(ABSTRACT TRUNCATED AT 250 WORDS)

Possible role of Streptococcus pyogenes in mucocutaneous lymph node syndrome. XI. Immunoelectron microscopic observation of protoplast-like "spherical bodies" detected in peripheral blood of MCLS patients.

Protoplast-like "spherical bodies" averaging 0.5-1.5 microns in diameter and devoid of cell walls were first detected by Ueno et al, in the buffy coat of heparinized venous blood from patients with mucocutaneous lymph node syndrome (MCLS). But the nature of the "bodies" has yet to be clarified because of the absence of convincing evidence pointing to their antigenic characteristics. The present investigations were designed solely to provide a serological identification of the "bodies" by the use of immunoelectron microscopy, with the following results. First, "spherical bodies" bearing a striking resemblance to those observed by the above-mentioned authors were detected in biopsy specimens from challenge sites in mice infected with Streptococcus pyogenes as well as in the buffy coat of peripheral blood from MCLS patients. Second, the "bodies" detected were stained distinctly in both cases by an immunohistochemical technique using, as the primary antibody, a rabbit antiserum raised toward S. pyogenes-derived protoplasts, which was then absorbed with protoplasts from Staphylococcus aureus and Escherichia coli. Third, the absorbed sera were proved to be not faultless, because complete specificity toward protoplasts from S. pyogenes was not attained due to the presence of a large amount of cross-reactive antigens between protoplasts from the immunizing and absorbing strains of bacteria. The implications of these findings are discussed, particularly in relation to the evaluation of the present serological test for the "spherical bodies".

Possible Role of Streptococcus Pyogenes in Mucocutaneous Lymph Node Syndrome XIII. No Recovery of β‐Hemolytic Streptococci from Pharynx of MCLS Patients

Lack of recovery of beta-hemolytic streptococci from the throat of 80 patients finally diagnosed as mucocutaneous lymph node syndrome was again confirmed, although alpha-hemolytic streptococci were consistently isolated from all patients but one. The implications of these findings were discussed, particularly in terms of the possible role of Streptococcus pyogenes in the pathogenesis of this disease.

Possible Role of Streptococcus Pyogenes in Mucocutaneous Lymph Node Syndrome. XII. Variable Responses of Platelets in MCLS Seem to Be Explainable by Streptococcal Pyrogenic Exotoxin

As a model system for mucocutaneous lymph node syndrome (MCLS), we have advocated and used mice which had been rendered tolerant to Streptococcus pyogenes-associated antigens by neonatal infection with group A beta-hemolytic streptococci, because these mice have shown a variety of peculiar bioimmunological characteristics bearing a striking resemblance to those of MCLS patients. The results of our current investigations reaffirmed the reliability of the animal model by indicating that mice subjected to neonatal infection with S. pyogenes, or inoculation with streptococcal pyrogenic exotoxin (SPE) in Freund's adjuvant, were perfect counterparts of patients with MCLS on account of their platelet activation and hyperaggregability in response to provocative treatment, which are familiar findings in this disease.

Possible role of Streptococcus pyogenes in mucocutaneous lymph node syndrome. III Electron microscopic observations on group A hemolytic streptococci inoculated into mice.

AbstractBecause of various circumstantial evidence, we have been asserting the streptococcal etiology of mucocutaneous lymph node syndrome (MCLS), although there has been no recovery of Streptococcus pyogenes from the patients at any site.The present study was designed to provide a satisfactory explanation for the failure to isolate these bacteria from patients with MCLS, by electron microscopic observation of group A ftera‐hemolytic streptococci which had been inoculated intramuscularly into mice.“Spherical bodies” were detected in biopsy specimens obtained from the infection sites from 10 – 14 days onward after infection; these were spherical, 0.5–1.5 yua in diameter, devoid of cell walls, perhaps uncultivable on any culture medium, and undistinguishable from those discovered in the buffy coat from peripheral blood of MCLS patients and described as ruined etiological microorganisms by Ueno et al.The implications of these findings, particularly in terms of the etiology of MCLS, were discussed.