Flashcards in Interstitial Lung Disease 1 - Clinical Aspects Deck (24):
What actually is the interstitium?
Interstitium = stuff between the alveolar epithelial cells and capillary endothelial cells.
Contains connective tissue stuff like collagen, elastin, reticulin, ECM, other proteins.
2 broad mechanisms of injury to interstitium?
Direct injury with response and repair.
Infiltration of interstitium.
If inflammation / fibrosis is deposited in interstitium, what happens to the lung?
(compliance, volume, air flow, gas exchange, etc.)
(static) Compliance reduced.
(static) Lung volume reduced.
Airflow typically is preserved.
Gas exchange impaired - due to impaired diffusion and V/Q mismatch.
4+ broad categories of interstitial lung disease (ILD)? (aka diffuse parenchymal lung disease -DPLD)
DPLD of known etiology - esp. drugs or collagen vascular disease.
Idiopathic Pulmonary Fibrosis (IPF).
Idiopathic other than IPF (including acute interstial PNA).
Granulomatous DPLD (esp. sarcoidosis).
Other - (eg. LAM)
What are pneumoconioses?
Dust-induced diseases (eg. asbestosis, silicosis)
What's the basis of diagnosis of an interstitial lung disease?
Typically you need to get lots of different data points:
History and physical.
CXR and HRCT.
Response to therapy.
(just like... many diseases)
Typical symptoms of interstitial lung disease? (4 things)
Cough, usu. dry.
Dyspnea, esp with exertion.
Chest pain, wheezing, hoarseness.
Systemic symptoms: fever, joint pain, rashes, dysphagia etc.
(kind of a silly thing to list... lots of diseases, lots of different constellations of symptoms...)
4 typical physical examine findings in interstitial lung disease?
Tachypnea, shallow breathing.
Dry, "velcro" crackles.
Clubbing of digits (present in up to 50% of cases).
3 non-lung findings in CXR/HRCT that can help with Dx of interstitial lung disease?
Methods of biopsy?
Transbronchial - for stuff that runs near larger airways.
What does "usual interstitial pneumonia" (UIP) refer to?
The pattern of damage seen in histology of IPF.
Most sensitive HRCT finding for IPF?
What does temporal heterogeneity refer to?
There are different lesions of varying ages in the biopsy sample - this is seen in IPF.
Is IPF the only thing that can cause UIP?
Nope... other things like collagen vascular disease, drug exposure, chronic sensitivity, asbestosis etc. can cause UIP.
(UIP is very sensitive, but not specific for IPF)
HRCT UIP is more specific for IPF than biopsy UIP.
Okay. But it's still not 100%.
(... but if you see UIP on both you can be pretty sure it's IPF?)
Median survival for IPF?
Treatments so far don't seem to help.
Age range for when people develop sarcoidosis?
Bimodal - peak in 20s, and peak in 50s.
Histological "hallmark" of sarcoidosis?
Necessary, but not specific, for diagnosis.
DDx for non-caseating granulomas?
Infection (mycobacteria, fungi)
Exposures: Beryllium, talc
Do most patients with sarcoidosis have symptoms?
Organ most commonly affected by sarcoidosis?
lungs (which is why we're talking about it)... but it can hit pretty much everything else.
When working up sarcoidosis...
check on all the organ systems it could affect.
Make sure it's not TB, etc.
3 forms of cutaneous sarcoidosis?