Pathology of Pneumonia Flashcards Preview

Week 6: Pneumonia and Cough > Pathology of Pneumonia > Flashcards

Flashcards in Pathology of Pneumonia Deck (15):
1

Generally the types of organisms responsible for
1. Intra alveolar
2. Interstitial
pneumonia

1. Bacterial
2. Viral

2

Pneumonia refers to inflammation of the...

Pulmonary parenchyma
Often associated with consolidation of the lung

3

3 ways to classify pneumonia anatomically

Lobar pneumonia
Bronchopneumonia
Interstitial pneumonia

4

6 predisposing factors for pneumonia

Suppression of cough reflex (anesthesia, coma, etc)
Impaired systemic immunity
Impaired mucociliary apparatus
Impaired alveolar macrophage function
Pulmonary edema
General debility (alcoholism, post-op, malnourishment)

5

Lobar pneumonia

Characterized by an area of uniform consolidation of part of a lobe or entire lobe
Most common type of CAP
Majority due to strep pneumo
Lobar distribution is a function of the virulence of the bacterial organism and vulnerability of the host

6

4 stages of lobar pneumonia

1. Congestion (intra-alveolar fluid, few neutrophils, numerous bacteria)
2. Red hepatization (massive intra-alveolar neutrohils with RBCs and fibrin)
3. Grey hepatization (macrophages replace neutrophils and ingest debris)
4. Resolution (but complications may ensue)

7

Bronchopneumonia

Patchy infective consolidation of the lung in a lobular distribution
Common (esp in hospitalized patients and as a terminal event)
Usually bilateral
Pre-exisiting bronchitis spreads to cause bronchiolitis and extends to adjacent lung parenchyma

8

4 complications of bacterial pneumonia

Bacteria dissemination (bacteremia)
Lung abscess formation (S aureus and anaerobes)
Empyema
Death

9

Lung abscess and 2 common causes

Contains purulent exudate and surrounded by a fibrous wall
Most common cause is aspiration
S aureus and anaerobic bacteria from oropharynx

10

Macroscopic and microscopic appearance of pulmonary TB

Macro: caseation necrosis
Micro: necrotizing granulomatous inflammation

11

Appearance of interstitial pneumonia under a microscope

Thickened alveolar walls
Heavily infiltrated with mononuclear leukocytes (lymphocytes and monocytes) (not PMNs like bacterial pneumonia)

12

5 causes of interstitial pneumonia

Viruses
Rickettsia
Chlamydia
Mycoplasma
Pneumocystis jiroveci (carinii)

13

Fungal appearance in
1. Immunocompromised
2. Immunocompetent

1. Fungal hyphae
2. Fungal spores

14

4 pathologies of fungal pneumonia in immunocompromised

Necrotizing pneumonia
Angioinvasion
Tissue infarction
Systemic dissemination

15

Pneumocystic jiroveci pneumonia

Alveoli are filled with a foamy exudate
Interstitium is thickened and contains a chronic inflammatory cell infiltrate