Path - Lung Infxns

Question 1

name 4 special stains for dx

Answer 1

gram stain, ziehl-neelson, silver, mucicarmine

Question 2

mucicarmine stains what two things?

Answer 2

mucin & cryptococcus

Question 3

bacterial infection leads to (location, inflammatory cell)?

Answer 3

intra-alveolar neutrophils

Question 4

viral infection leads to?

Answer 4

interstitial lymphocytes

Question 5

mycobacteria and fungi lead to?

Answer 5

granulomatous inflammation (giant cells, epithelioid histiocytes, lymphocytes) in the interstitium, stroma, and LNs

Question 6

bacterial pneumonia causes what two presentations on CXR?

Answer 6

lobar pneumonia OR bronchopneumonia (scattered foci of consolidation)

Question 7

who is most likely to get bronchopneumonia?

Answer 7

terminally ill patients, older pts

Question 8

what type of bacteria cause bronchopneumonia?

Answer 8

ANY bacteria

Question 9

what organisms cause lobar pneumonia?

Answer 9

strep pneumo, klebsiella

Question 10

which community acquired organisms are necrotizing?

Answer 10

klebsiella, staph aureus, anaerobic strep (GBS), pseudomonas

Question 11

most common cause of secondary bacterial infection after a virus

Answer 11

strep pneumo (encapsulated gram positive diplococci)

Question 12

what is “red hepatization”?

Answer 12

early pathology of pneumococcal pneumonia: pulm edema, prolif of bacteria, intra-alveolar accum of neutrophils and RBCs

Question 13

what is “gray hepatization”?

Answer 13

late pathology of pneumococcal pneumonia: serum and fibrinous exudates, intra-alveolar organization, macrophages

Question 14

legionella pneumonia

Answer 14

bronchopneumonia with wide range of severity, small gram neg bacillus, aquatic environments

Question 15

how is legionella different from most forms of bacterial pneumonia?

Answer 15

neutrophils necrose –> necrotic debris

Question 16

what is the primary cause of anaerobic bacterial pneumonia?

Answer 16

aspiration in susceptible patients (anesthesia, alcoholism, seizure disorder)

Question 17

anaerobic bacteria cause necrosis, leading to?

Answer 17

foul smelling sputum, possible abscess or gangrene

Question 18

name 2 filamentous bacteria

Answer 18

actinomyces israelii, nocardia asteroides

Question 19

this bacteria causes “sulfur granules”

Answer 19

actinomyces israelii

Question 20

how do you distinguish between actinomyces and nocardia?

Answer 20

nocardia positive on acid-fast bacilli stain (AFB)

Question 21

filamentous bacteria form?

Answer 21

abscesses

Question 22

name 3 complications of bacterial pneumonia

Answer 22

abscess, empyema, bacteremia

Question 23

abscesses are common/rare, usually found in this lung, and more common in pts with ______

Answer 23

rare, right lung, alcoholism

Question 24

what is pyothorax (empyema)?

Answer 24

infection of pleural fluid, can become loculated and form an abscess

Question 25

bacteremia can lead to?

Answer 25

endocarditis, meningitis, pericarditis

Question 26

also known as “walking” pneumonia

Answer 26

mycoplasma pneumoniae

Question 27

describe the microbiology of mycoplasma

Answer 27

slow-growing prokaryote without a cell wall (dx serologically)

Question 28

describe the pneumonia course caused by mycobacteria

Answer 28

milder course, causing acute pneumonia and tracheo-bronchitis, highly transmissible (airborne droplets)

Question 29

histology of mycoplasma infection shows?

Answer 29

acute inflammation of wall and lumen of bronchiole, alveoli generally clean

Question 30

is TB fast or slow growing?

Answer 30

slowwww

Question 31

primary TB results in ____ 90% of the time

Answer 31

Ghon complex formation (peripheral nidus + infected hilar LN) which walls off bacteria (no sx)

Question 32

what type of granuloma is seen in TB?

Answer 32

necrotizing (coagulative/caseous) in the center, with rim of histiocytes and giant cells

Question 33

special stain for TB

Answer 33

acid fast bacilli look red on blue background

Question 34

two forms of secondary TB

Answer 34

new infection in previously sensitized pt OR reactivation of primary TB

Question 35

pathology of secondary TB

Answer 35

numerous caseating granulomas in apical/posterior of upper lobes –> focal cavities (can erode into blood vessels causing hemoptysis)

Question 36

complications of TB

Answer 36

miliary TB (hematogenous spread to organs), hemoptysis, empyema, cavity –> aspergilloma

Question 37

histoplasma capsulatum (tiny) found in?

Answer 37

miss and ohio river valleys

Question 38

coccidioides (large) found in?

Answer 38

southwestern US, “San Joaquin Valley”

Question 39

cryptococcus (yeast) and histoplasma spread through?

Answer 39

bird droppings

Question 40

this fungi can be identified through a mucin stain

Answer 40

cryptococcus (thick cell wall)

Question 41

this fungus mimics TB

Answer 41

histoplasma

Question 42

this fungus mimics a neoplasm

Answer 42

cryptococcus

Question 43

this fungus shows septate hyphae with acute angle branching

Answer 43

aspergillus

Question 44

3 types of aspergillus

Answer 44

invasive, aspergilloma, ABPA

Question 45

invasive aspergillosis may lead to?

Answer 45

infarct, thrombosis, or exsanguination

Question 46

aspergillomas commonly form inside?

Answer 46

cavities caused by secondary TB

Question 47

ABPA shows high levels of what in the serum?

Answer 47

eosinphils and IgE

Question 48

pathology of PCP

Answer 48

cysts fills alveolar spaces with organisms and frothy exudates

Question 49

a silver stain of PCP shows?

Answer 49

cup-shaped organisms

Question 50

viral pneumonia most frequently occurs in this population

Answer 50

immunocompromised (HIV, organ transplant)

Question 51

cytomegalovirus (CMV) shows ____ on histo

Answer 51

large cells with intranuclear inclusions (owl’s eye inclusions)

Question 52

Herpes virus shows ____ on histo

Answer 52

large cells with multiple, molded nuclei