CP6 Benign lung pathology Flashcards
What are important factors for a good airway?
Good support
Good wall strength
Appropriate size lumen
What can affect the amount of air transported in gas exchange?
More airflow
The size and number of the areas for gas exchange
What is the key aspect of inflammation that leads to narrowing of lumen?
Swelling due to leaky fluid from the vessels.
What are released by neutrophils in acute inflammation?
Proteases and active oxygen species
How does the releases of chemicals by neutrophils affect local tissues?
Non specific so can damage healthy cells leading to more inflammation
What is a swelling in the lungs or arteries due to fluid known as?
Ectasia
How do tissues respond after an episode of acute inflammation?
Complete resolution
Chronic inflammation
Loss of tissue
Scarring
What consequences of inflammation can affect gas exchange in the lung tissue?
Scarring, loss of tissue and chronic inflammation (least effect of the 3)
What is an example of a disease associated with loss of lung tissue?
Emphysema
What happens when pressure increases in areas of the lung affected by emphysema?
The area of the lung collapses obstructing the passage of air
What is a consequence of emphysema?
Reduction in capillary beds increasing capillary resistance making the right side of the heart pump harder leading to right ventricular hypertrophy
What is scarring in the lung known as?
Fibrosis
What is a consequence of lung fibrosis?
Reduces elasticity of the lungs
How is asthma triggered?
Sensitisation to trigger followed by a re-exposure to trigger causing airway narrowing
How does asthma affect the lungs?
Thickens alveolar walls due to inflammation and tissue hyperplasia, contraction of smooth muscle in the airways and increased production of mucus in the lumen
How does asthma present clinically?
SOB, wheeze, cough and hyperinflation
What are 3 common triggers of asthma?
Allergens, NSAIDs, cold
What occurs in the lungs with bronchitis?
Inflammation and increased goblet cells and overlying luminal mucus
Most common cause of chronic bronchitis is….
Smoking
What two conditions are encompassed in COPD?
Emphysema and chronic bronchitis
How is COPD triggered?
Chemical and heat trigger inflammation in bronchitis and lung parenchyma. In the bronchi there is persistent inflammation, scarring and mucus hyperplasia. In the parenchyma, inflammation leads to emphysema.
How are the lungs affected in bronchiectasis?
Dilated bronchus and muco-purulent debris in lumen
What is bronchiectasis?
Permenant dilation if the bronchi and bronchioles due to wall damage secondary to chronic necrotising infection.
What triggers bronchiectasis?
Mainly obstruction leading to infection - usually by a tumour or thick mucus in CF patients - and also de novo infections, leading to inflammation damaging wall tissues leading to dilation containing inflammatory debris and muscles.
What are symptoms and signs of bronchiectasis?
Productive cough +/- haemoptysis
Recurrent infections
Obstructive ventilatory defects
What is chronic ILD?
Reduction of lung compliance due to scarring +/- inflammation
What are examples of diseases classes as chronic ILDs?
Idiopathic pulmonary fibrosis (IPF)
Pneumoconiosis
Sarcoidosis
Hypersensitivity pneumonitis (HP)
What does the lung look like in chronic IPF diesease?
Lung mixed with areas of fibrosis and areas of normal alveoli
What part of the lungs is mainly affected by chronic IPF?
Lower zones of both lungs
What is the mean survival time for people with chronic IPF?
3 years
What are the triggers for chronic IPF?
Idiopathic
What is the lung like in pneumoconiosis?
Contains coal dust and areas of fibrosis
What happens to a scar over time?
The affected tissue contracts
What causes pneumoconiosis?
Lung damage secondary to partial inhalation (most commonly coal, asbestos or silica) from occupational exposure. Damage is a result of the particles being ingested by macrophages causing fibrosis
What are present in the lungs in sarcoid?
Granulomas
How does sarcoid trigger issues in the lung?
Non-caseating granulomas trigger scarring aka fibrosis
What body parts are affected by sarcoid?
Lungs and lymph nodes
Who is most likely to get sarcoid?
Those aged 20-60, more in North Africa and Europe and in non smokers
How does HP affect the lungs?
Interstitium widened by inflammatory infiltrate leading to fibrosis
What causes hypersensitivity pneumonitis (HP)?
Inhaled organic antigens (e.g. mould, hay, animal faeces, paint fumes etc..) triggering a hypersensitivity response leading to inflammation and fibrosis (if the antigen isn’t removed)
How does CF affect the lungs?
Production of abnormally thick mucus and pus blocking the lumina leading to infections, inflammation and scarring.
How does CF affect the pancreas?
Exocrine atrophy leading to malabsorption
