Type I Pneumocyte
Flattened region of gaseous transport/diffusion, susceptible to injury.
Type II Pneumocyte
Site of surfactant production.
Can proliferate and reform alveolar epithelial surfaces.
What are Interstitial Lung Diseases?
More than 200 distinct diseases arising from the inflammation and/or fibrosis of the pulmonary interstitium.
Includes most of pulmonary medicine that isn't airways (asthma/COPD), infections, pleural disease.
Common Clinical Presentations for ILD
Approach to ILDs
Known causes (environmental/occupational, drugs/radiation)
Idiopathic interstitial pneumonias (most common is IPF)
Lots of others
Idiopathic Interstitial Pneumonias
A subset of interstitial lung dieases.
The most common of this category by far is idiopathic pulmonary fibrosis (IPF).
Idiopathic Pulmonary Fibrosis (IPF)
Is a chronic and ultimately fatal disease characterized by a progressive decline in lung function.
Treatment is with pirfenidone and nintedanib.
Approach to Environmental/Occupational Exposures
Inorganic - silicosis, asbestosis, diametomaceous earth, aluminum oxide, berylliosis, etc.
Pneumoconioses - hard metal, coal workers, wood burning, etc.
Organic - bird fanciers, farmers, duck fever, sauna takers, coffee workers
Common Drugs and ILD
Nitrofurantoin - an antibiotic used to treat bladder infections
Methotrexate - anti-metabolite
Amiodarone - class III antiarrythmic drug
Bleomycin - used in cancer treatment
Physical Exam Findings - ILD
Hands - cyanosis and clubbing
Chest - velcro crackles, inspiratory squeaks, expiratory wheeze
CVS - signs of pulmonary hypertension, right ventricular failure
Is a radiological appearance seen with widespread fibrosis and is defined by the presence of small cystic spaces with irregularly thickened walls composed of fibrous tissue.