History

• Streptococcus anginosus group was formerly called the Strep milleri group

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Taxonomy

• Members of Viridans Group Strep (VGS) (see Viridans Group Streptococci, [[Viridans Group Streptococci]]): these typically are Vancomycin-sensitive
  • Strep anginosus Group
    • Strep anginosus
    • Strep constellatus
    • Strep intermedius
  • Strep mitis Group (see Streptococcus Mitis Group, [[Streptococcus Mitis Group]])
    • Strep mitis
    • Strep gordonii
    • Strep oralis
    • Strep sanguis
    • Strep parasanguis
  • Strep salivarius Group (see Streptococcus Salivarius Group, [[Streptococcus Salivarius Group]])
    • Strep salivarius
    • Strep thermophilus
    • Strep vestibularis
  • Strep bovis Group (see Streptococcus Bovis Group, [[Streptococcus Bovis Group]])
    • Strep bovis
    • Strep equinus
    • Strep alactolyticus
  • Strep mutans Group (see Streptococcus Mutans Group, [[Streptococcus Mutans Group]])
    • Strep mutans
    • Strep rattus
    • Strep cricetus
    • Strep downei
    • Strep sobrinus
    • Strep macacae

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Microbiology

• Organisms
  • Strep anginosus: isolated from larger range of sites
  • Strep constellatus: isolated from larger range of sites
  • Strep intermedius: tropism for brain and liver
• Commensal Organisms
  • Oropharynx
  • Gastrointestinal Tract
  • Vaginal Flora
  • Skin

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Diagnosis

• PCR-Based Methods: usually necessary to idnetify organism
  • Difficult to diagnose based on phenotypic characteristics

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Clinical Manifestations

General Comments

• May Manfest Extension Across Tissue Planes: including interlobar fissure, diaphragm, and chest wall
  • This is a unique characteristic

Cardiovascular Manifestations

• Endocarditis (see xxxx, [[Endocarditis]]): less commonly associated than other viridans group strep species
  • Strep intermedius rarely causes endocarditis

Gastrointestinal Manifestations

• Liver Abscess (see Liver Abscess, [[Liver Abscess]])

Neurologic Manifestations

• Brain Abscess (see Brain Abscess, [[Brain Abscess]])

Pulmonary Manifestations

• Lung Abscess (see Lung Abscess, [[Lung Abscess]])

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References

• Streptococcus anginosus infections: crossing tissue planes. Chest. 2014 Oct;146(4):e121-5. doi: 10.1378/chest.13-2791 [MEDLINE]