Obstructive And Restrictive Lung Diseases Flashcards
What is the difference between an obstructive lung disease and a restrictive lung disease?
Obstructive lung diseases are characterized by an obstruction to air flow anywhere from the trachea down the respiratory tree. A restrictive lung disease is the lungs not able to expand fully so total lung capacity has decreased.
What is going on with the FEV/FVC ratio in obstruction and restrictive lung diseases?
Restrictive normal and obstructive lower.
What are the 4 most common obstructive lung diseases?
Emphysema, chronic bronchitis, asthma and bronchiectasis.
Emphysema and chronic bronchitis are categorized as what condition and what is the most often cause?
COPD. Smoking.
What is the requirement for diagnosis chronic bronchitis?
Persistent cough with sputum production for at least 3 months over a 2 year period.
What is the predominant pathophysiologic mechanism of Chronic Bronchitis?
Mucous gland hyperplasia with associated thickening of the smooth muscle
Besides tons of mucus secretion, what 2 other things characterize Chronic Bronchitis?
Inflammation and infection
What 2 inflammatory cytokines do we see in chronic bronchitis?
IL 13 and histamine
hallmark histo feature of chronic bronchitis?
Increased size of mucus glands
What is the Reid index and what does it have to do with chronic bronchitis?
Ratio of the thickness of the mucus gland vs. the thickness of the whole wall that the gland sits in. Normal is usually .4 but increases over .5 with chronic bronchitis.
What is the cardinal symptom of chronic bronchitis?
Persistent, productive cough of sputum
How do we characterize emphysema?
Irreversible enlargement of the airspace distal to the terminal bronchiole with destruction of their walls.
What are the 4 types of emphysema, which two cause clinically significant obstruction and which one is most common?
Centriacinar, panacinar, paraseptal, and irregular. First two are clinically significant. Centriacinar is most common.
Which alveoli are involved in centriacinar, what part of the lung, and what condition is it associated with?
Proximal and central alveolar are affected, distal are spared. Upper lobes usually. COPD.
What alveoli are involved in panacinar emphysema, what part of the lung and what condition is it associated with?
Whole acinus or basically all the alveoli in the unit. Lower lobes. Alpha 1 antitrypsin deficiency.
What does alpha 1 antitrypsin usually do?
Coats the lungs and protects it from neutrophil elastase damaging the lungs.
What part of the acinus is damaged in paraseptal emphysema, where in the lung and what condition does this type of emphysema underlie?
Distal is affected. Upper lobe near the septa of the lobules. This type underlies spontaneous pneumothorax.
Irregular emphysema is associated with what in the acinus?
Scarring.
3 Mechanisms of alveolar damage in emphysema?
Inflammatory mediators, proteases, and oxidative stress leading to cell death.
What is the genotype of these patients with panacinar emphysema and what is the chromosome association?
homozygous PiZZ from chromosome 14.