Pulmonary Infections

Question 1

Pneumonia is infection of what part of the lung?

Answer 1

parenchyma

Question 2

What are the three histological patterns of pneumonia?

Answer 2

Bronchopneumonia (patchy)

Lobar pneumonia/ typical
pneumonia (entire lobe or portion of a lobe)

Interstitial (atypical) pneumonia

Question 3

What is a big IVDU cause of pneumonia?

Answer 3

Staph aureus

Question 4

What are the stages of inflammatory response in pneumonia?

Answer 4

• congestion
• red hepatization
• gray hepatization
• resolution

Question 5

What is the congestion phase of inflammatory response to pneumonia characterized by?

Answer 5

vascular engorgemnet and edema, few PMNs, and numerous bacteria

Question 6

What is the red hepatizationphase of inflammatory response to pneumonia characterized by?

Answer 6

Masive congestion, and abundant PMNs and fibrin

Question 7

What is the grey hepatizationphase of inflammatory response to pneumonia characterized by?

Answer 7

Disintegration of RBCs and macrophages, Fibropurulent exudate

Question 8

What is the resolution phase of inflammatory response to pneumonia characterized by?

Answer 8

Enzymatic digestion and resolution by macrophages

Question 9

What pneumonia sources cause necrotizing pneumonia (e.g. can cause abscess formation)?

Answer 9

streptococcus, Klebsiella

Question 10

When pneumonia causing bacteria spread to the pleural cavity, it is called ____

Answer 10

emphyema

Question 11

How is atypical pneumonia different?

Answer 11

• less sputum production

- neutrophilic alveolar exudate typically lacking

Question 12

How does Legionella transmission typically occur?

Answer 12

Naturally in the environment, usually in water (grow best in warm water, like the kind found in cooling tanks)

Notspread from one person to another person

Question 13

What does Legionella require to grow?

Answer 13

cysteine and iron (doesn’t grow on BAP)

Question 14

How does Legionella present histologically?

Answer 14

Extensive bronchopneumonia to lobar pneumonia with intra-alveolar neutrophils, macrophages, fibrin; often with leukocytoclastic neutrophilic infiltrate, small vessel vasculitis and necrosis

Question 15

Aspiration pneumonia presents where most commonly?

Answer 15

right lower lobe due to the anatomy of the lungs and bronchi

Question 16

What is a good indication of aspiration pneumonia on H&E?

Answer 16

foreign body giant cells

Question 17

Primary TB is more commonly found in what part of the lung?

Answer 17

lower (2ndary more common in the apex)

Question 18

What is a good indication of TB on H&E?

Answer 18

langhans giant cells and caveating granulomas

Question 19

How does Mycobacterium tuberculosis organisms, many of which are present within macrophages, appear as with an acid fast stain?

Answer 19

red rods

Question 20

Which fungal pneumonia commonly produces granulomas?

Answer 20

Histoplasmosis

Question 21

Which cause of pneumonia gives the characteristic ‘owl’s eyes’ appearance?

Answer 21

CMV pneumonia