Lung Pathology #1

Question 1

Pathology of Bronchiectasis: What is it and what is the basic pathogenesis?

Answer 1

• Chronic disorder characterised by permanent dilatation of the bronchi accompanied by inflammatory changes in their walls and in adjacent lung parenchyma
• Pathogenesis: recurrent inflammation of the bronchial walls combined with fibrosis in the surrounding parenchyma leads to traction on weakened walls causing irreversible dilatation

Question 2

Pathology of Lung abscesses: What is a lung abscess? What is the most common cause? What are 3 associated contributing factors? What kind of bacteria (class) are most common?

Answer 2

• Localised necrotic cavity containing pus

• Most common cause is aspiration, associated with bacterial pneumonia
• 3 factors: altered consciousness, poor dental hygiene, immune suppression
• Anaerobic bacteria common

Question 3

What are the two classes of causes of bronchiectasis, and the causes of each (know 3 examples of each)

Answer 3

Post-inflammatory (non-obstructive):
• Pneumonia, measles, whooping cough
• Congenital hypogammaglobulinemia, cystic fibrosis, immotile cilia syndrome
• Allergic bronchopulmonary aspergillosis
• Reactions to inhaled toxic fumes

Post-obstructive:
•  Neoplasm
•  Foreign body
•  Inspissated mucus: asthma
•  External compression: hilar lymph nodes, aorQc aneurysm •  Rarely bronchial webs or atresia

Question 4

Which bronchi and bronchioles are most likely to be affected by bronchiectasis?

Answer 4

Lowe lobe, distal bronchi and bronchioles

Question 5

Are lung abscesses more common in the R or L lung? Why?

Answer 5

R lung, RMB is more vertical.

Question 6

What is an example of a non-bacterial lung abscess?

Answer 6

Aspergillosis

Question 7

What are the characteristics of mycobacterium TB?

Answer 7

Mycobacteria are aerobic, non-motile

bacilli

Question 8

What is a Gohn’s complex?

Answer 8

area of necrotizing granulomatous inflammation in the lung (usually R upper lobe or upper portion of R lower lobe) (Ghon’s focus) and in draining lymph nodes (Ghon’s complex): combination of peripheral lung and LN lesions in primary TB

Question 9

What % of patients with primary TB progress with progressive TB?

Answer 9

10%

Question 10

What is cavitary fibrocaseous tuberculosis?

Answer 10

• By erosion into a bronchiole, drainage of the caseous focus transforms it into a cavity
• The infective material may now disseminate through the airways to other sites in the lung or upper respiratory tract

Question 11

What are favoured sites for distal seeding of TB? (5)

Answer 11

Bone marrow, liver, spleen, kidney, LNs

Question 12

What are 2 important factors which are risks for the reactivation of TB?

Answer 12

Corticosteroids and HIV infection