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STREPTOCOCCI

STREPTOCOCCI. Streptococci facultative anaerobe Gram-positive chains or pairs catalase negative (staphylococci are catalase positive). Streptococcus in chains. Streptococcus pneumoniae (diplococcus). Fluorescent stain. Streptococci Lancefield groups

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STREPTOCOCCI

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  1. STREPTOCOCCI

  2. Streptococci • facultative anaerobe • Gram-positive • chains or pairs • catalase negative • (staphylococci are catalase positive)

  3. Streptococcus in chains

  4. Streptococcus pneumoniae (diplococcus). Fluorescent stain

  5. Streptococci • Lancefield groups • Satu atau lebih spesies per group • antigen permukaan

  6. groupablestreptococci • A, B and D • most important • C, G, F • rare

  7. Non-groupable • S. pneumoniae • pneumonia • viridans streptococci • e.g. S. mutans • dental caries

  8. hemolysis reaction - sheep blood agar • α (alpha) • partial hemolysis • green color • β (beta) • complete clearing • A and B • γ (gamma) • no lysis

  9. Hemolysis • Groups A an B • β • Group D • α or γ • S. pneumoniae and viridans • γ

  10. hemolysis reaction + one characteristic • presumptive identification

  11. Group A streptococcus(S. pyogenes)

  12. Group A streptococcal menginfeksi semua umur • Insiden tertinggi pd usia 5-15 thn

  13. S. pyogenes -suppurative • non-invasive • pharyngitis • Infeksikulit, impetigo • invasive bacteremia • toxic shock-like syndrome • "flesh eating" bacteria • pyrogenic toxin

  14. Pyrogenic toxin • superantigen • T cell mitogen • Mengaktifkan sistem imun

  15. Scarlet fever • rash • erythrogenic toxin

  16. non-suppurative • rheumatic fever • inflammatory disease • life threatening • Sekuel kronik • demam • jantung • sendi • rheumatic tidak sama dengan rheumatoid arthritis

  17. Rheumatic fever -etiology • M protein • cross-reacts heart myosin • autoimun • Antigen dinding sel • sedikit dicerna in vivo • bertahan lama

  18. Rheumatic fever • penicillin • menyembuhkan pharyngitis • Menurunkan resiko carditis

  19. Acute glomerulonephritis • immune complex disease of kidney

  20. Major pathogenesis factors • lipoteichoic acid/F protein • fimbriae • binds to epithelial cells • M protein • anti-phagocytic

  21. M protein • major target • Imunitas alami • strain variation • antigenicity • re-infection • Terjadi dengan strain yg berbeda

  22. Capsules • Anti-phagocytic • mucoid strains

  23. Isolation and identification • β hemolytic colonies • bacitracin menghambat pertumbuhan • β hemolytic colonies • group A antigen

  24. β hemolysis • hemolysin O • Sensitif oksigen • hemolysin S • Non sensitive oksigen

  25. Post-infectious diagnosis (serology) • Antibodi thd streptolysin O • Penting! Bila menetap sekuel kronik terjadi

  26. Serotyping • M • T • R

  27. Group B streptococcus • neonatal meningitis • septicemia • transmission • vaginal flora

  28. Group B streptococcus - identification • β hemolysis • hippurate hydrolysis • CAMP reaction • meningkatkan βhemolisis S. aureus

  29. Group D streptococcus • Tumbuhpada bile esculin agar • precipitasihitam 6.5% salin • Tumbuh • enterococci • Tidaktumbuh • non-enterococci

  30. Enterococci • Hubungannya agak jauh dr streptococci lain • genus Enterococcus • Flora usus • urinary tract infection • Kontaminasi dr anus • opportunistic infections • khususnya endocarditis • Paling sering E. (S.) faecalis

  31. Enterococci • resisten thd banyak antibiotik • termasuk vancomycin • ujung D-ala diganti dengan D-lactat

  32. Minute colony streptococci • Various groups (e.g. group A) • berbeda scr genetik • koloni yg besar (e.g. S. pyogenes) • tdk ada demam rheuma Koloni besar Koloni kecil

  33. Viridans streptococci • diverse species • oral • Karies gigi • α hemolytic dan negatif thd tes lain • non-groupable. • termasuk S. mutans • endocarditis • cabut gigi

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