Interstitial Lung Disease 2 Flashcards
What structure is affected in interstitial lung disease?
Interstitial lung disease (ILD)
aka Diffuse Parenchymal Lung Disease (DPLD)
• a group of diseases affecting the interstitium (tissue and space around the alveolar sacs of the
lung)
Pathophysiology of interstitial Lung disease
- injury to the lung —> abnormal healing response —> incorrect repair process —> tissue around #
- the alveoli become scarred and thickened
- scarred and thickened tissue —> more difficult for the oxygen to pass into blood stream
Symptoms of Interstitial Lung Disease?
SOB on expiration, non-productive paroxysmal cough, restrictive pulmonary, spirometry, abnormal breath sounds, decreased tolerance to exercise
What can be seen on examination of a patient with Interstitial Pulmonary Disease?
O/E: inspiratory crackles, cyanosis and finger clubbing (later stage)
Management of Interstitial Pulmonary Disease
- if specific environmental factor is a contributor —> a person should avoid that environment
- if a drug is suspected to be a cause —> discontinuation of a drug
- many cases of an unknown cause or connective tissue disorder —> corticosteroid treatment
(e.g. prednisolone) ; some respond to immunosuppressants
- supportive treatment with oxygen
- Pulmonary rehabilitation
- Lung transplant - if other forms of treatments fail and if there are no other contradictions
Examples of substances potentially causing Idiopathic Lung Disease re to occupation
asbestosis, berylliosis, silicosis, cotton worker’s lung
Examples of substances potentially causing Idiopathic Lung Disease re to drugs
nitrofurantoin, bleomycin
Examples of substances potentially causing Idiopathic Lung Disease re to allergy
extrinsic allergic alveolitis
Examples of substances potentially causing Idiopathic Lung Disease re to infections
TB, fungi, viral
What other systemic diseases ILD can be associated with?
- Sarcoidosis
- Rheumatoid arthritis
- Systemic sclerosis, connective tissue disease, Sjogren’s syndrome
Pathophysiology of Idiopathic Pulmonary Fibrosis
- idiopathic trigger of the process
- Fibrosis occurs usually after tissue damage —> ongoing repair process —> excess collagen/ scar tissue in the interstitial space of the lungs —> chronic process —> progressive loss of lung tissue
Risk factors for Idiopathic Pulmonary Fibrosis (3)
old age, being male, tobacco smoking
What is the location of Idiopathic Pulmonary Fibrosis and cells involved
Interstitial tissue (contains macrophages and fibroblasts)
What happens (pathology) in Idiopathic Pulmonary Fibrosis?
- Damage to epithelium —> type 2 pneumocyte over- proliferate (during the repair process)—> too many myofibroblasts —> too much collagen
- Myofibroblasts do not undergo apoptosis —> more and more collagen is produced —> collagen accumulates —> interstitial layer between alveoli and capillary forms —> problems with ventilation and oxygenation
- Excess collagen (also causes)—> lungs becoming stiff —> hard for air to flow in and out —>
restricted lung expansion (due to fibrosis in interstitium)