Pathology: pneumonia

Question 1

What are these two types of pneumonia?

Answer 1

Left: bronchopneumonia
Right: lobar pneumonia

Question 2

Bronchopneumonia
- Involves which type of inflammation?

Answer 2

Suppurative inflammation

Question 3

Lobar pneumonia
- Is most commonly caused by which bacteria?
- What are the four stages of lobar pneumonia?

Answer 3

Streptococcus pneumoniae

Stages
- Congestion
- Red hepatisation
- Grey hepatisation
- Resolution

Question 4

Lobar pneumonia stages
- Congestion

Answer 4

Question 5

Lobar pneumonia stages
- Red hepatisation

Answer 5

Question 6

Lobar pneumonia stages
- Grey hepatisation

Answer 6

Question 7

Lobar pneumonia stages
- Resolution

Answer 7

Question 8

What are the settings pneumonia can be acquired within?

Answer 8

Community acquired pneumonia
Healthcare acquired pneumonia
Hospital acquired pneumonia
Ventilator acquired pneumonia
Aspiration pneumonia
Pneumonia in an immunocompromised host
Chronic pneumonia

Question 9

Community acquired pneumonia
- What are the 4 typical bacteria?
- Which one is the most common cause of community acquired pneumonia?

Answer 9

Streptococcus pneumoniae (most common cause)
Haemophilus influenzae
Moraxella catarrhalis
Staphylococcus aureus

Question 10

Community acquired pneumonia: typical bacteria
- Haemophilus influenzae and moraxella catarrhalis are associated with?
- Staphylococcus pneumonia usually occurs?

Answer 10

Acute exacerbations of COPD
Secondary to viral infection

Question 11

Community acquired pneumonia
- What are some atypical bacteria

Answer 11

Mycoplasma pneumoniae
Legionella pneumophilia
Chlamydophila pneumoniae/psittaci/trachomatis
Coxiella Burnetti (Q fever)
Tuberculosis
Pseudomonas spp
Klebsiella pneumoniae

Question 12

Community acquired pneumonia: atypical bacteria
- What are they associated with?

Answer 12

Question 13

Community acquired pneumonia: viral
- What is the most common cause?

Answer 13

Influenza

Question 14

Community acquired pneumonia: viral
- Other causes?

Answer 14

COVID/coronaviruses, RSV, parainfluenza virus, human metapneumovirus, pertussis, adenovirus, rhinovirus, varicella, rubeola

Question 15

Healthcare acquired pneumonia
- Organisms?

Answer 15

Streptococcus pneumoniae
Staphylococcus aureus - methicillin sensitive and resistant (MRSA)
Pseudomonas aeruginosa

Question 16

Hospital acquired pneumonia
- Organisms?

Answer 16

MRSA
Pseudomonas spp
Enterobacter (eg. Klebsiella pneumoniae)

Question 17

Aspiration pneumonia
- What happens?
- Difference from aspiration pneumonitis
- Risk factors

Answer 17

Vomit is aspirated; and aerobes (lung microbes) and anaerobes (oral + gut microbes) enter the lungs

Aspiration pneumonitis is when acidity of the vomit leads to chemical irritation of the respiratory tract (non infectious)

Risk factors
- Compromised gag reflex - stroke/brain injury, AOD (loss of consciousness), dysphagia
- Repeated vomit

Question 18

Aspiration pneumonia
- Examples of aerobic and anaerobic bacteria found in aspiration pneumonia?

Answer 18

Aerobic bacteria: streptococcus pneumoniae, haemophilus influenzae, staphylococcus aureus, pseudomonas aeruginosa

Anaerobic oral flora: Bacteroides, Prevotella, Fusobacterium, Peptostreptococcus

Question 19

Pneumonia in an immunocompromised host
- Bacterial organisms?

Answer 19

Question 20

Pneumonia in an immunocompromised host
- Bacteria: fun facts?

Answer 20

Question 21

Pneumonia in an immunocompromised host
- Viruses: which ones?

Answer 21

CMV, human metapneumovirus, herpes virus

Question 22

Pneumonia in an immunocompromised host
- Fungi: which ones?

Answer 22

Question 23

Pneumonia in an immunocompromised host
- Fungi: fun facts?

Answer 23

Question 24

Chronic pneumonia
- Is it often a localised lesion in immunocompetent patients?
- Can it involve regional lymph nodes?
- Type of inflammation?
- Example of bacteria and fungi causing chronic pneumonia

Answer 24

Yes
Yes
Granulomatous
Bacteria: M. tuberculosis; fngi: histoplasmosis

Question 25

4 complications of pneumonia?

Answer 25

• Lung abscess
• Empyema
• ARDS
• Sepsis