Streptococcus Pneumoniae

Question 1

Microbiological Properties of Strep. pneumoniae?

Answer 1

• Gram Positive
• Encapsulated
• Diplococci
• Lancet shaped
• IgA protease

Question 2

How does strep. pneumoniae respond to Optochin and bile?

Answer 2

Optochin sensitive an Bile soluble

Question 3

Strep pneumoniae are naturally transformable how?

Answer 3

Virulence and antibiotic resistance is a result of horizontal gene transfer

Question 4

What kind of hemolysis do you notice with strep pneumoniae?

Answer 4

Alpha hemolytic on blood agar

Question 5

strep pneumoniae commonly colonizes what?

Answer 5

Nasopharynx and oropharynx

Question 6

The highest incidence of carriage and disease occurs during what?

Answer 6

Cool months

Question 7

Role of streptococcus capsule VF?

Answer 7

Antiphagocytic and antigenic

Question 8

Role of streptococcus Pneumolysin VF?

Answer 8

Cytotoxic to epithelial cells of lung and in phagocytes. activates complement then inflammation

Question 9

Role of streptococcus IgA Protease VF?

Answer 9

Promotes adherence and colonization.

Question 10

Role of streptococcus Autolysin VF?

Answer 10

(LytA) Induces inflammation and the release of pneumolysin.

Question 11

Role of streptococcus Pneumococcal surface protein VF?

Answer 11

(pspA, pspB) inhibits complement deposition and binds choline.

Question 12

What is the most importnat VF for Strep pneumoniae?

Answer 12

CAPSULE (complex polysaccharide)

Question 13

what is a Quellung Reaction?

Answer 13

Swelling that occurs when capsule specific antibody reacts with capsule.

Question 14

most of the damage is due to what in Step pneumoniae?

Answer 14

Majority of damage due to host response, not toxin mediated.

Question 15

Pneumococcus produces what that leads to host cell damage?

Answer 15

H2O2

Question 16

Pneumolysin can kill what?

Answer 16

Can kill airway epithelial cells

Question 17

Pneumococcal infection causes non-invasive diseases like?

Answer 17

• Sinusitis (sinuses)
• Otitis media (middle ear)
• Pneumonia (lungs)

Question 18

Pneumococcal infection also causes invasive diseases like?

Answer 18

Bacteremia which leads to:

• Meningitis
• Endocarditis
• Peritonitis
• Septic arthritis

Question 19

Pneumococcal Pneumonia onset?

Answer 19

bacteria grow in edema fluid in alveolar spaces –> Erythrocytes leak into alveoli –> neutrophils and macrophage infiltrates

Question 20

Pneumococcal Pneumonia clinical findings?

Answer 20

• “rusty” sputum
• Rapid onset
• shaking chills
• Blood-tinged sputum
• Empyema (pus w/in pleural spaces)

Question 21

What is the m.c reason for childhood medical visits?

Answer 21

Otitis media from Strep pneumoniae (pneumococcus)

Question 22

Apart form 40-50% of Otitis media caused by Pneumococcus, other organisms that cause this are…?

Answer 22

• Haemophilus influenza

- Moraxella catarrhalis

Question 23

Pneumococcus are generally resistant to what drugs?

Answer 23

Penicillins, Macrolides (erythcromycin), and Tetracyclines

Question 24

Treatment of strep pneumoniae for patients allergic to penicillin?

Answer 24

Ceftriaxone

Question 25

What is the treatment for SERIOUS pneumococcal infections?

Answer 25

• Fluoroquinolone or Vancomycin combined with Ceftriazone

Question 26

You can give conjugate vaccines for Strep. pneumoniae to whom?

Answer 26

(Prevnar) under 2 year old infants at 2,4,6, and 12-15 months

Question 27

Polysaccharide vaccines are typically given to whom?

Answer 27

typically for adults or those with pre-existing conditions. (Pneumovax)

Question 28

Strep pneumoniae is the most common cause of what 4 things?

Answer 28

'MOPS'
Meningitis
Otitis media (in children)
Pneumonia
Sinusitis