Sketchy Micro: Streptococcus Pneumoniae and Streptococcus Viridans

Question 1

How will beta and alpha hemolysis appear?

Answer 1

Beta is golden and alpha has a green hue

Question 2

S. pneumoniae and S. viridans are unique in that they are _______ hemolytic.

Answer 2

alpha (like the alpha knight tournament)

Question 3

S. pneumoniae is covered by a ______________.

Answer 3

polysaccharide capsule (like the knight covered with armor)

Question 4

S. pneumoniae is ____________ sensitive.

Answer 4

optochin (like the knight’s exposed chin)

Question 5

What shape does S. pneumoniae have under microscopy?

Answer 5

Lancet-shaped diplococci (like the pneumo knight’s two lances)

Question 6

Strep. pneumoniae is ________-soluble.

Answer 6

bile (like the bile on the horse’s feet)

Question 7

What kind of pneumonia does S. pneumoniae cause?

Answer 7

Lobar with rust-colored sputum (like the rust on the knight’s armor)

Question 8

S. pneumoniae is the most common cause of which four infections?

Answer 8

Meningitis in adults
Otitis media
Pneumonia
Sinusitis

(Think of the knight’s squire with the MOPS and the fan with the #1 sign near him.)

Question 9

S. pneumoniae has a protease that cleaves ___________.

Answer 9

IgA dimers (like the IgA dimers on the knight’s cracked shield)

Question 10

What population of patients are particularly vulnerable to Strep. pneumo infections?

Answer 10

Those who have undergone splenectomy (represented by the knight’s sickle, because many people with sickle cell have had splenectomies).

Question 11

What two treatments are best for infections with S. pneumoniae?

Answer 11

Macrolides and ceftriaxone (think of the crows watching the jousting and the three axes on the knight’s flag).

Question 12

Describe the vaccine options for S. pneumoniae.

Answer 12

Children receive a kind that is capsule complexed to protein that generates IgG, and adults receive a vaccine the is not conjugated to protein and thus leads to an IgM response.

(Think of the sign telling Adults to go to the Mezzanine and Children to go to the Ground.)

Question 13

What are three ways to differentiate between S. pneumoniae and S. viridans?

Answer 13

S. viridans does not have a capsule (just like the unprotected jester that faces the knight).

S. viridans is optochin resistant (just like how the jester has a protective mask over his chin).

S. viridans is bile insoluble (just like how the jester’s donkey is wearing protective shoes in the mud).

Question 14

S. viridans is common in what infection?

Answer 14

Damaged mitral valve endocarditis. It does so by adhering to platelets and dextrans (like the jester’s plate and DECK of cards).