Final

Question 1

Acute Pneumonia - community acquired –> which bugs?

Answer 1

S. pneumoniae
H. influenza
Influenza virus

Question 2

Acute pneumonia - nosocomial –> which bugs?

Answer 2

Staph aureus

gram negatives

Question 3

Acute pneumonia - opportunistic –> which bugs?

Answer 3

pseudomonas
pneumocystis
CMV
adenovirus
herpes

Question 4

Acute stage of pneumonia

Answer 4

polys in alveoli

macrophages later

Question 5

Resolving stage of pneumonia

Answer 5

polys gone
many macrophages
infiltrates are cleared
alveolar walls intact

Question 6

Organizing stage of pneumonia

Answer 6

granulation tissue in terminal bronchioles & alveoli

fibrosis

Question 7

What are the stages of pneumonia?

Answer 7

Acute –> resolving –> organizing

Question 8

What is the typical causative organism for lobar pneumonia?

Answer 8

Strep pneumoniae

Question 9

Which 2 spots is aspiration pneumonia most likely to settle?

Answer 9

Posterior segment of upper lobe

Superior segment of lower lobe

Question 10

What is used to ID the legionella bacteria?

Answer 10

Dieterle silver stain

Question 11

When would you see prominent basophilic inclusions?

Answer 11

Atypical pneumonia caused by adenovirus

Question 12

When would you see prominent eosinophilic nuclear inclusions?

Answer 12

Atypical pneumonia caused by herpes simplex virus

Question 13

When would you see both nuclear AND cytoplasmic inclusions?

Answer 13

Atypical pneumonia caused by CMV virus

Question 14

When would you see oval-crescentic GMS+ cysts?

Answer 14

Pneumocystis jiroveci (carinii) pneumonia

Question 15

When would you see an abundance of plasma cells in the alveolar walls?

Answer 15

Pneumocystic jiroveci (carinii) pneumonia

Question 16

When would you see a gram stain with lots of WBCs but no organisms?

Answer 16

Legionella pneumonia

Question 17

What would you think if the patient isn’t responding to “conventional” antibiotics?

Answer 17

Could be legionella pneumonia, esp if the cultures don’t reveal a pathogen

Question 18

What is the best way to diagnose legionella? Be specific.

Answer 18

Culture!

-use BCYE –> buffered charcoal yeast extract, supplemented & made selective

Question 19

When would you see a bullous otitis media?

Answer 19

Mycoplasma infection

Question 20

Spherules are pathognomonic of what?

Answer 20

Coccidiodes immitis (dimorphic fungi)

Question 21

Where is Coccidiodes immitis endemic?

Answer 21

Southwest US

Question 22

Where is Histoplasma capsulatum endemic?

Answer 22

Central US

Question 23

What is the mechanism of action of amphotericin B?

Answer 23

Binds to Ergosterol (the primary fungal cell membrane sterol)
Direct toxicity to cell membrane –> punches holes in it, making it more leaky

Question 24

What is the mechanism of action of azoles?

Answer 24

Inhibits the cytochrome P450 which converts lanosterol to ergosterol (the primary fungal cell membrane sterol)
Interferes with cell membrane synthesis

Question 25

In general, uses of fluconazole?

Answer 25

Active against yeasts, NOT against molds

Question 26

what is the mechanism of action of echinocandins?

Answer 26

inhibit the fungal beta(1,3)-glucan synthase | depletes beta-glucan, a ubiquitous fungal cell wall constituent

Question 27

Dirty pneumonia

Answer 27

adenovirus

Question 28

Etiology of otitis media

Answer 28

Streptococcus pneumoniae - 35-40% Nontypable H influenzae - 25-30% Moraxella catarrhalis - 15-20%

Question 29

Spread of Hib v. NTHI

Answer 29

Hib spreads through hematogenous means | NTHI spreads locally

Question 30

Hib v. NTHI evolutionary history

Answer 30

Hib is clonal | NTHI is genetically diverse

Question 31

Causative pathogens for COPD exacerbations

Answer 31

H. influenzae > Moraxella catarrhalis > Strep pneumoniae > Pseunomonas aeruginosa

Question 32

Strep pneumoniae v. other viridans strep

Answer 32

Strep pneumoniae is optochin sensitive | Other viridans strep are optochin resistant

Question 33

Mechanism of strep pneumoniae intermediate penicillin resistance

Answer 33

transformation with penicillin binding protein genes from closely related species

Question 34

Mechanism of strep pneumoniae high level penicillin resistance

Answer 34

trasformation with penicillin binding proteins genes from closely related species + spontaneous mutations

Question 35

Rx for penicillin suceptible pneumococcal pneumonia

Answer 35

penicillin cephalosporins fluoroquinolones

Question 36

Rx for penicillin resistant pneumococcal pneumonia

Answer 36

``` penicillin (high doses) cephalosporins fluoroquinolones vancomycin linezolid ```

Question 37

What bug might you see after the use of a lot of carbapenems?

Answer 37

Stenotrophomonas maltophilia

Question 38

First choice drug for Pneumocystis jiroveci (Pneumocystis carinii)

Answer 38

Trimethoprim-sulfamethoxazole

Question 39

most common extrapulmonary site for nocardia infection

Answer 39

Brain

Question 40

Primary treatment for nocardia infection

Answer 40

Sulfonamides

Question 41

Ecthyma gangrenosum is strongly associated with which infection?

Answer 41

Pseudomonas aeruginosa

Question 42

What infections do you see with terminal complement deficiencies (C6-C9)?

Answer 42

Neisseria, esp Neisseria meningitidis

Question 43

Treatment of lung abscess

Answer 43

Clindamycin

Question 44

Lung abscess characterized by what?

Answer 44

Foul-smelling sputum | history of poor dentition & loss of consciousness

Question 45

Treatment of allergic bronchopulmonary aspergillosis

Answer 45

Itraconazole (antifungal) + steroid

Question 46

What is the mechanism of action of terbinafine (lamisil)

Answer 46

inhibits squalene epoxidase, an enzyme involved in ergosterol synthesis

Question 47

What is the major use of flucytosine?

Answer 47

in combination with amphotericin B for cryptococcal meningitis

Question 48

What is the mechanism of action of flucytosine

Answer 48

inhibits fungal protein synthesis by replacing uracil with 5-flurouracil in fungal RNA (& also interferes with fungal DNA synthesis)

Question 49

Major flucytosine toxicities

Answer 49

bone marrow suppression & GI toxicity

Question 50

How to culture mycobacterium

Answer 50

Does NOT grow on routine lab media | grow in lowenstein-jensen agar