Diffuse Parenchymal Lung Disease Flashcards
What is the pathophysiology in parenchymal lung disease?
Lung interstitium becomes expanded by an inflammatory cell infiltrate (pneumonitis). This impairs gas exchange and causes breathlessness.
What is this a presentation of?
Dyspnoea on exertion, non-productive cough, abnormal breath sounds, abnormal CXR, restrictive pulmonary spirometry.
Diffuse parenchymal lung disease
What are the known causes of diffuse parenchymal lung disease?
- Occupational/environmental (asbestosis, silicosis, coal worker)
- Drugs - nitrofurantoin, amiodarone, sulfasalazine
- Hypersensitivity reactions
- Infections - TB, fungal, viral
- GORD
Which systemic disorders is diffuse parenchymal lung disease associated with?
- Sarcoidosis
- RA
- SLE, connective tissue disease, Sjogren’s syndrome
- UC, autoimmune thyroid disease, renal tubular acidosis
What is the treatment for idiopathic pulmonary fibrosis?
Supportive, oxygen, high dose steroids, palliative care.
What is the work-up for a suspected diffuse parenchymal lung disease?
- Meticulous history including occupational and environmental exposure in detail.
- CXR may show reticular-nodular shadows
- High resolution CT
- Lung biopsy for histological examination is sometimes needed for diagnosis but is not first line.
What are the long-term complications of diffuse parenchymal lung disease?
- Cor pulmonale
- Fibrosis of the lung tissue causes obliteration of pulmonary arterioles - gradual development of pulmonary hypertension