Pathology of Obstructive Lung Disease Flashcards
What are some OBSTRUCTIVE lung diseases?
- emphysema
- chronic bronchitis
- asthma
- bronchiesctasis
air is trapped in the lungs and cant get out
What is atelectasis?
collapse of previously inflated lung resulting in relatively airless pulmonary parenchyma
What are the types of atelectasis?
- resorption (obstruction)
- compression
- contraction
Describe resorption atelectasis
airway obstruction due to mucus or tumor that causes respiration of trapped O2 in dependent alveoli and shifts the mediastinum toward the affected lung
Describe compression atelectasis
filling of pleural cavity by tumor, blood, or air that causes compression of pulmonary tissue causing the mediastinum to move AWAY from the affected lung
Describe contraction atelectasis
fibrotic lung or pleura preventing full expansion of the lung
Which type of atelectasis is not reversible?
contraction
What is emphysema?
permanent enlargement of airspaces caused by destruction of their walls
T or F. Fibrosis is a significant feature of emphysema
F.
What are the types of emphysema?
- centroacinar
- panacinar
- paraseptal
Where is centracinar emphysema predominant?
upper lobes due to smoking (smokes rises)
Where is panacinar emphysema predominant?
lower lobes due to AIAT deficiency
What type of emphysema probably underlies spontaneous pneumothorax in young adults?
paraseptal
Where is A1AT made and what does it do?
liver and goes to the lung and neutralizes protease release by inflammatory cells
What else may accompany A1AT deficiency?
liver cirrhosis (the misfiled protein accumulated in ER of hepatocytes). PAS positive hyaline nodules
What is the normal allele for A1AT?
PiMM
What are the most common mutations of A1AT?
PiZ and PiS
Describe the severity of disease in PiMZ patients
low levels of A1AT so normally okay unless they smoke
PiZZ patients are at risk for what?
panacinar emphysema and liver cirrhosis
Centriacinar emphysema affects what part of the lung?
respiratory bronchioles (distal is not affected)
Panacinar emphysema affects what part of the lung?
from respiratory bronchioles distal
Paraseptal emphysema affects what part of the lung?
alveoli
What is the cause of paraseptal emphysema?
unknown
How is chronic bronchitis defined?
persistent cough with sputum at least 3 months in at least 2 consecutive years
Histologic manifestations of Chronic bronchitis?
- submucosal gland hypertrophy of large airways (Reid Index)
- increased goblet cells in small airways
- peribronchial fibrosis
- chronic inflammation
What kinds of cells surround the bronchial epithelium in chronic bronchitis?
lymphocytes (lymphocyte rich infiltrates)
What are the types of asthma?
1) Extrinsic- type I hypersensitivity
2) Intrinsic- non-immunologic reaction precipitates by infection, stress, exercise, etc.
Gross features of asthma?
- overinflation of lungs
- mucous plugs
Microscopic features of asthma?
- thickened BM
- gland and smooth muscle hypertrophy
- eosinophil-rich infiltrates
Asthamtic mucuous often contains ____
Charcot-Leyden crystals (formed from dead eosinophils) OR
Curschmann spirals
What causes Curschmann spirals?
when mucous gets into fluid it curls
What is Bronchiestasis?
permanent airway dilation associated with smooth muscle and elastic tissue destruction leading to fibrosis of airway walls
What are some causes of Bronchiectasis?
1) congenital (Cystic fibrosis, Immotile cilia syndromes like Kartagener)
2) Necrotizing pneumonia (e.g. Mycobacteria, Staph)
3) Bronchial obstruction
What is a T-E fistula?
failure of fetal RT to seperate from the GI tract. Most common (86%) is a connection between the trachea and GI with a blind pouch
Branching tubes from the ___ give rise to the trachea, bronchi, and bronchioles
foregut
Between 26-32 weeks, what happens to fetal lung?
surfactant production begins
When do alveoli begin to differentiate?
7 months
What are the stages of alveolar differentiation?
- glandular
- saccular (surfactant made here)
- alveolar
What happens during the alveolar stage?
reduction of interstitial tissues and increasing capillaries
When are the lungs histologically mature?
8 yo
