MICRO-STREPTOCOCCUS + cocci Flashcards
Grows in pairs or in chains
Streptococcus
Streptococcus are
gram positive cocci, and facultative anaerobes
T/F: Streptoccoccus requires lancefield classification and haemolysis pattern on blood agar
True
Which Streptococcus species fall on the Beta (B) group
- Group A: S Pyogenes (in pharynx of kids)
- Group B: S agalactiae ( colonize the vaginal, urethra, in both men and women, and GIT)
- Group C: S dysgalactiae
- Group D: S Bovis
- Group D: enterococci
- GRP ACFG: S. anginosus group
Which streptococcus species fall on the alpha (a) group?
- S pneumoniae (upper respiratory tract; nasopharynx)
- Viridans streptococci ( oropharynx)
Non-invasive diseases from streptococcus pneumoniae (its pathogenesis)
pneumonia, sinusitis, otitis media, conjuctivitis
Invasive diseases from S. pneumoniae (pathogenesis)
bacteremia, meningitis, endocarditis, peritonitis
Virulence factors of Sreptococcus pneumoniae
- The capsule
-Autolysin
-Pneumolysin
-Pneumococcal surface protein A (PsPA)
A species which is a human commensal, colonizing the oral mucosa, GIT, and GUT
Viridans Group Streptococci
Species that a part of the normal intestinal flora
enterococci
Most prevalent enterococci species on human (intestinal flora organisms)
-Enterococcus faecalis
-Enterococcus faecium
Virulence factors of S. pyogenes
Somatic Constituents:
- hyaluronic acid
- Mprotein
-Lipoteichoic acid
Extracellular products:
- Streptolysin O
- Streptolysin S
- DNAse
- Hyaluronidase
- Steptokinase
- C5a peptidase
A virulence factor of S pyogenes responsible for lyses of cells incl RBSs ( is also responsible for Beta haemolysis)
Streptolysin O
Diseases caused by streptococcus agalactiae
- postpartum infection
-neonatal sepsis (blood stream infection in newborns)
-Bacteriamia
-early neonatal sepsis and late neonatal sepsis
