Chapter 7

Question 1

What are 3 common developmental abnormalities of the lung in children?

Answer 1

1. Bronchial Atresia
2. Bronchogenic Cysts (precursor is atresia): accessory bronchial buds which become sealed off from the rest of the airway
3. Bronchopulmonary sequestration - portion of lung that does not communicate with normal bronchial tree

Question 2

What is the pathogenesis of neonatal respiratory distress syndrome?

Answer 2

Deficiency of surfactant in the lungs, usually due to prematurity

Surfactant is secretred by type 2 pneumocytes; reduces surface tension in the alveoli and keeps them open

Alveolar collapse causes hypoxia due to damage to endothelial and alveolar lining cells and fibrin exudation (hyaline membranes)

Question 3

What is neonatal respiratory distress syndrome?

Answer 3

Deficiency of surfactant in the lungs, usually due to prematurity

Surfactant secreted by type 2 pneumocytes; reduces surface tension in alveoli and keeps them open

alveolar collapse causes hypoxia, damage to endothelial and alveolar lining cells and fibrin exudation

Question 4

Apart from neonatal respiratory distress syndrome, name and explain two other childhood diseases that affect the lungs.

Answer 4

1. immotile cilia syndrome
   - cilia have abnormal structure or are unable to beat in coordinated fashion, resulting in recurrent infections
2. cystic fibrosis
   - common autosomal recessive disorder in caucasions (1 in 25 heterozygous carriers)
   - production of abnormally viscous mucus that cannot be cleared from lungs, pancreas, intestines
   - stagnant mucus results in repeated infections and bronchiectasis - pts due from infection or respiratory failure in early adulthood