1. GRAM POSITIVE COCCI erly Gram positive and negative bacteria: The cell wall very different:. Peptidoglycan  very strong, thick and rigid.. Teichoic acid  surface antigen.

2. Species cause of human disease: Staphylococcus aureus Streptococcus pneumoniae Streptococcus pyogenic ect

3. Structure and function Capsule  antiphagocytosis Peptidoglycan  stimulate production of endogenous pyrogens Protein spesific:A,M,F  antiphagocytosis,anticomplementary Teichoic acid  attachment to mucosal

4. Pathogenesis and Immunity The virulence is determined by: a variety of structural molecule and elaborated toxins and enzymes.  virulence factors

5. Toxins - Exotoxin : 1. Cytotoxin 2. Enterotoxin  food poisoning.resistant to gastric &jejunal enzymes..heat stable.stimulate intestinal peristaltic

6. Enzymes. Coagulase  fibrin layer. Catalase  H2O2. Hyaluronidase  spreading factors. Lipase. Fibrinolysin. Penicillinase. Ig A protease. Hemolysin : Streptolysin O  antigenic

7. Important features of pathogenesis Staphylococcus aureus 1. Pyogenic (abscess) - local  skin infection surgical wound infection - disseminated  sepsis 2. Toxigenic  food poisoning

8. Staphylococcus epidermidis Pyogenic  iv catheter sites & prostetic devices Staphylococcus saprophyticus Pyogenic  UTI(Urinary Tract Infection )

9. Streptococcus pyogenes 1.Pyogenic. Local : skin,pharing. Disseminated : sepsis 2. Toxigenic 3. Immune-mediated(post Streptococcal infection,non suppurative)

10. Poststreptococcal disease Immunologic response to streptococcal M protein that cross-react with human tissues. 1.Acute Glomerulonephritis antigen-antibody complexes on glomerular. 1.Acute Rheumatic Fever autoimmune disease

11. Streptococcus pneumoniae Pyogenic :. Pneumonia. Otitis media. Meningitis