Pneumonia, Rheumatic Fever, Endocarditis

Question 1

What bacteria causes most pneumonia?

Answer 1

strep pneumoniae

Question 2

What are the predisposing conditions that make pneumonia more likely in some people?

Answer 2

impeded drainage from lungs

HF, viral infection, immobility, foreign bodies, suppressed cough reflex, smoking, allergies

Question 3

How do you diagnose strep pneumoniae?

Answer 3

clinical features, DIRECT EXAMINATION of SPUTUM for presence of DIPLOCOCCI, culture for abx sensitivity

Question 4

step pneumoniae is _____ hemolytic, gram ______, ___cocci, lancefield group ______, ______ sensitive

Answer 4

alpha hemolytic
gram positive
doplicocci
lancefield group negative
bile/ optochin sensitive

Question 5

Strep pneumoniae reservoir

Answer 5

throat 5-50% of people

Question 6

strep pneumoniae toxins

Answer 6

leucocidins

Question 7

what type of capsule does strep pneumoniae have? What functions does it serve?

Answer 7

polysaccharide capsule; antigen and virulence factor –> stimulates opsonizing antibody AND impedes phagocytosis

Question 8

How is the strep pneumonia vaccine made? Who should get it?

Answer 8

polysaccharide capsule is used in the polyvalent vaccine

-elderly or susceptible patients

Question 9

how do you treat strep pneumoniae?

Answer 9

PCN/erythromycin, drug resistance has increased so vancomycin is the alt.
*test for drug sensitivity

Question 10

When is pneumonia most common? Why?

Answer 10

Winter–> close quarters–> viruses spread–> pneumonia predisposition

Question 11

What are the other common causes of pneumonia besides strep pneumoniae?

Answer 11

klebsiella pneumoniae, S. aureus, Group B step, HACEK gram negative rods

Question 12

What is a rheumatic fever?

Answer 12

post-streptococcal condition that arises ~3 wks after resolution of sore throat caused by group A stre

Question 13

A 9yo patient with fever, polyarthritis, endocarditis, myocarditis presents to your clinic. Her sx started a few months ago after a strep infection. What do you think the diagnosis is?

Answer 13

Rheumatic fever

kids 6-15 are the at-risk group

Question 14

What will you find if you culture the lesions of rheumatic fever?

Answer 14

NOTHING; the lesions are sterile because it is a post-strep condition

Question 15

How do you diagnose rheumatic fever?

Answer 15

clinical features + IgM anti-streptolysin O Ab + sterile lesions + inflamed joints are sterile + Aschoff body

Question 16

Although the pathogenesis of rheumatic fever has not been directly demonstrated, it is thought to be:

Answer 16

auto-immune
certain M-protein types (M5, M3) are more likely to be assoc. with Rheumatic Fever
certain HLA types are more common in pts

Question 17

Why are rheumatic fever patients at life-long risk for endocarditis?

Answer 17

Rheumatic fever endocarditis can cause fibrosis or calcification of the endocardium which can distort and damage the valves permanently

Question 18

What is the treatment for Rheumatic Fever?

Answer 18

anti-inflammatory drugs, no abx! May require valve replacement

Question 19

When do you treat Rheumatic Fever patients with abx?

Answer 19

Pts with a hx of RF should have aggressive abx tx if they have subsequent strep infections

Question 20

What are the virulence factors of endocarditis?

Answer 20

extracellular polysaccharides (make the bacteria “sticky” and create vegitations

Question 21

splinter hemorrhages under the fingernails and conjunctiva indicate _________.

Answer 21

edocarditis

Question 22

What are the bacteria that commonly cause endocarditis?

Answer 22

S. viridans, IV drug users sometimes get endocarditis from S. aureus, HACEK gram negative rods also cause endocarditis

Question 23

Post-streptococcal conditions, such as RF, are assoc. with variants in which aspect of streptococcus>

Answer 23

The M protein