Streptococcus Pneumoniae, B. Pertussis, Mycobacterium Flashcards Preview

D1S U1 Microbiology > Streptococcus Pneumoniae, B. Pertussis, Mycobacterium > Flashcards

Flashcards in Streptococcus Pneumoniae, B. Pertussis, Mycobacterium Deck (15):
1

Main cause of community acquired pneumonia worldwide. Also causes otitis media (in kids) and meningitis in adults.

Streptococcus pneumoniae

2

4 Stages of Pathogenesis of Streptococcus Pneumoniae:

1. Alveoli fill with fluid
2. Early consolidation phase (suppurative inflammation)
3. Late consolidation phase (alveoli and airways are packed with neutrophils, affected tissue is solid not spongy)
4. Recovery phase (macrophages phagocytose debris, normal architecture re-established)

3

____ is a parasite of Protozoa found in contaminated water and spread by environmental aerosols. Virulent strains multiply within ____ (double membrane of rough ER)

L. Pneumophila (Legionella Pneumophila)

Autophagosomes

4

L. Pneumophila:
1. Effective Drugs

2. Ineffective Drugs

1. Macrolides, Fluoroquinolones, Tetracyclines (intracellular penetration)

2. Penicillins (not effective because they don't achieve therapeutic concentrations in macrophages)

5

Streptococcus Pneumoniae:
1. Gram stain?
2. Oxygen dependence?
3. Can it be isolated? How?

1. Gram positive
2. Aerotolerant anaerobe
3. Yes, Catalase negative -> optochin susceptibility

6

Major reservoirs of Streptococcus Pneumoniae:

-Young kids
-Nasopharyngeal mucosa

Transmitted by respiratory secretions/hands

7

Legionella Pneumophila:
1. Gram stain?
2. Oxygen dependence?
3. Can it be isolated? How?

1. Gram negative
2. Obligate aerobe
3. Yes, fastidious (special conditions for cultivation in lab), cysteine requirement is identifying characteristic

8

Legionella pneumophila: Virulence/Proinflammatory mechanisms:

1. Survival in macrophages
2. LPS, Flagellin (enhances inflammation)

9

Bordetella Pertussis and Parapertussis
1. Gram stain?
2. Oxygen dependence?
3. Can it be isolated? How?
4. Reservoir?

1. Gram negative
2. Obligate aerobe
3. Nasal swab (culture)
4. Adults (nasopharynx)

10

Very contagious bacteria, cause of Whooping Cough

Bordetella pertussis and parapertussis

11

B. pertussis vs. P. Parapertussis toxin production:

B. Pertussis: pertussis toxin, adenylate cyclase/hemolysin, endotoxin

P. Parapertussis: no pertussis toxin

12

Clinical course of Whooping Cough:

1. Catarrhal stage (very runny nose, very contagious)
2. Paroxysmal Stage (whooping coughs)
3. Convalescent stage (gradual recovery)

13

Mycobacterium spp.
1. Gram stain?
2. Oxygen dependence?
3. Can it be isolated? How?
4. Diseases
5. Encounter thru

1. Gram negative
2. Obligate aerobes
3. Very slowly
4. Tuberculosis, Leprosy
5. Ingestion/Inhalation

14

Milder disease form of M. Leprae. May be self limiting. Very few bacteria present in lesions.

Tuberculoid Leprosy

15

Severe form of M. Leprae. Disfiguring, many organisms in lesions, cell mediated immunity decreased.

Lepromatous Leprosy