II. Epidemiology

  1. In 2022, there is an increase globally of invasive Group A Streptococcus and Scarlet Fever
    1. https://www.who.int/emergencies/disease-outbreak-news/item/2022-DON429
  2. Group A Streptococcus results in 700 million infections and complicated by 500,000 deaths each year worldwide
    1. Carapetis (2005) Lancet Infect Dis 5(11): 685-94 [PubMed]
  3. Post-streptococcal complications have become uncommon in the United States
    1. Complications are more common in Sub-Sahara Africa, India, Australia, New Zealand

III. Pathophysiology: General

  1. Anaerobic Gram Positive Cocci
    1. Beta-hemolytic Streptococcus (induces complete RBC Hemolysis in its vicinity)
    2. Lancefield Group A (C CarbohydrateAntigen) in Bacterial cell wall
    3. Pyogenes is derived from greek "pus forming"
  2. Humans are only reservoir
  3. Beta Hemolysis Factors
    1. Streptolysin O
      1. Inactivated by oxygen (oxygen labile)
      2. Lyses WBC and RBC (causing beta-Hemolysis)
      3. Measurable with acute infection (ASO Titer)
    2. Streptolysin S
      1. Oxygen Stable
      2. Also contributes to beta hemolytic activity
  4. Virulence Factors
    1. Hyaluronidase
    2. Anti-C5a Peptidase
    3. DNAase
    4. Streptokinase
      1. Activates plasmin, triggering Fibrinolysis (nearly identical to staphylokinase)
      2. Streptokinase is extracted from Group C Strep to be used in MI and Stroke (prior to tPA, TNK)
    5. Lipoteichoic Acid
      1. Aids in Bacterial adherence
    6. M Protein
      1. Inhibits Complement Activation
      2. Inhibits Phagocytosis, and allows for rapid subcutaneous spread (e.g. Necrotizing Fasciitis)
      3. M Protein also provides an Antigenic target for immune response to clear infection
  5. Toxins
    1. Pyrogenic exotoxin (erythrogenic toxin)
      1. Expressed by strains that cause Scarlet Fever
    2. Toxic Shock Syndrome Toxin (TSST)
      1. Exotoxins hyperstimulate T-Cell response with high Cytokine release (Toxic Shock Syndrome)
      2. Similar to Staphylococcal exotoxin
  6. Antibiotic management of Streptococcal Pharyngitis and decreases Rheumatic Fever risk
    1. However, does not prevent Post-Streptococcal Glomerulonephritis
  7. Autoimmune complications arise from Antibody formation against streptococcal M Protein
    1. Immune complex deposition in Post-Streptococcal Glomerulonephritis
    2. Antibody directed reaction in Acute Rheumatic Fever
    3. Autoantibody cross-reaction to Basal Ganglia in Sydenham Chorea

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Ontology: Streptococcus pyogenes (C0038411)

Definition (NCI_CDISC) Any bacterial organism that can be assigned to the species Streptococcus pyogenes.
Definition (NCI) A species of facultatively anaerobic, Gram positive, cocci shaped bacteria in the phylum Firmicutes. This species is beta hemolytic, Lancefield group A, pyrrolidonylarylamidase, and arginine deaminase positive and catalase negative. It can ferment salicin, rhamnose, and trehalose but not sorbitol, or ribose. S. pyogenes is found on normal human skin but can act as a pathogen causing streptococcal pharyngitis, acute rheumatic fever, scarlet fever, skin infections, acute glomerulonephritis and necrotizing fasciitis.
Definition (CSP) species of gram-positive, coccoid bacteria isolated from skin lesions, blood, inflammatory exudates, and the upper respiratory tract of humans; it is a group A hemolytic Streptococcus that can cause scarlet fever and rheumatic fever; virulent strains penetrate deep into the body, with catastrophic results; it has been demonstrated that invasive streptococcus A infections can trigger a toxic shock syndrome, myositis, or destroy the sheath that covers the muscle, necrotizing fasciitis.
Definition (MSH) A species of gram-positive, coccoid bacteria isolated from skin lesions, blood, inflammatory exudates, and the upper respiratory tract of humans. It is a group A hemolytic Streptococcus that can cause SCARLET FEVER and RHEUMATIC FEVER.
Concepts Bacterium (T007)
MSH D013297
SnomedCT 302594001, 67297007, 80166006
LNC LP15188-3, MTHU002582, LA20992-6
English Streptococcus Group A, Streptococcus group A, STREP PYOGENES, STREP GROUP A, Streptococc Lancefield group A, Streptococcus pyogenes, streptococcus group A, S. pyogenes, Group A Beta-Hemolytic Streptococcus pyogenes, streptococcus group, pyogenes s, pyogenes streptococcus, strep pyogenes, group streptococcus, streptococcus group a, pyogenes s., pyogenes strep, s. pyogenes, group a streptococcus, Streptococcus pyogenes Rosenbach 1884, STREPTOCOCCUS PYOGENES, streptococcus pyogenes, Micrococcus scarlatinae, Streptococcus erysipelatos, Streptococcus hemolyticus, Streptococcus scarlatinae, Streptococcus, group A (organism), Streptococcus Lancefield group A (organism), GROUP A BETA-HEMOLYTIC STREPTOCOCCUS PYOGENES, Group A streptococcus, Streptococcus, group A, Streptococcus pyogenes (organism), Streptococcus Lancefield group A, group A Streptococcus
French Streptococcus groupe A, Streptocoque du groupe A, Streptocoque pyogène, Streptococcus pyogenes
Swedish Streptococcus pyogenes
Czech Streptococcus pyogenes
Finnish Streptococcus pyogenes
Russian STREPTOKOKKI PIOGENNYE, STREPTOKOKKI GEMOLITICHESKIE, STREPTOKOKKI PATOGENNYE, STREPTOKOKKI GRUPPY A, STREPTOCOCCUS PYOGENES, СТРЕПТОКОККИ ГЕМОЛИТИЧЕСКИЕ, СТРЕПТОКОККИ ГРУППЫ A, СТРЕПТОКОККИ ПАТОГЕННЫЕ, СТРЕПТОКОККИ ПИОГЕННЫЕ
Japanese 連鎖球菌-A群, 化膿性連鎖球菌, A群レンサ球菌, 化膿レンサ球菌, 化膿連鎖球菌, ストレプトコッカス・ピオゲネス, A群連鎖球菌, ストレプトコッカスA群, 化膿性レンサ球菌
Italian Streptococco del gruppo A, Streptococcus pyogenes
Croatian STREPTOCOCCUS PYOGENES
Polish Streptococcus pyogenes, Paciorkowce ropne
Spanish estreptococo, grupo A, Streptococcus, grupo A, Streptococcus, grupo A (concepto no activo), Streptococcus Lancefield, grupo A (organismo), Streptococcus Lancefield, grupo A, Bacterias Comedoras de Carne, Streptococcus pyogenes (organismo), Streptococcus pyogenes, Streptococcus Grupo A
Portuguese Streptococcus Grupo A, Streptococcus do Grupo A, Streptococcus pyogenes
German Streptococcus Gruppe A, Streptococcus pyogenes
Dutch Streptococcus pyogenes, Streptococcusgroep A, Streptokokkengroep A, ß-hemolytische streptokokkengroep A

Ontology: Beta-hemolytic Streptococcus, group A (C1541907)

Concepts Bacterium (T007)
SnomedCT 413643004
English Streptococcus group A, GAS, Group A Strep, Group A beta-hemolytic streptococci, Beta-haemolytic Streptococcus, group A, Beta-hemolytic Streptococcus, group A (organism), Beta-hemolytic Streptococcus, group A
Spanish Streptococcus beta-hemolítico del grupo A (organismo), Streptococcus beta-hemolítico del grupo A