(pneumococcus) alpha hemolytic, causes pneumoniae, acute inflammation, capsule, gram +, no exotoxins, aerobic, peroxidase +, catalase -, C substance, fastidious
Purpose of capsules
Virulence, prevent phagocytosis
How does Strep pneumoniae cause disease?
causes an overwhelming inflammatory response NOT EXOTOXINS.
Classical manifestations of pneumococcus
Abrupt onset of symptoms, ill apprearance, rust-colored sputum, leukocytosis, bacteremia, etc.
Antibiotics effective against pneumococcus
Protects S. pneumoniae from infections of the same serotype
Antibodes to the capsule
choline containing teichoic acid that is part of the cell wall. All S. pneumoniae strains have the same.
Primitive non specific host defense mechanism against infection which reacts with C substance.
People more likely to be infected by pneumococcus
Children under 5, adults over 40, native americans, sicle cell anemia, HIV, Hodgkins, & abscence of spleen.
Protection again pneumococcus
Epiglottis, cough reflex, mucous, macrophages.
What organims cause meningitis? (3)
1. S. pneumoniae
2. Haemphilus influenzae
3. Neisseria meninditidis
W. Barry Wood
4 zones of lung involvement.
How is pneumococci differentiated from other streps?
lancet shape and sensitivity to optochin
Why is mortality high even though S. pneumoniae is sensitive to penicillin?
1. Rapidly progresses
2. Other diseases + S. pneumo kill them