Interstitial and Parenchymal Lung Disease Flashcards
What is a lobule in the lung?
Lung parenchyma bounded by pleira and interlobular septae (venules and lymphatics).
How many acini per lobule?
5-8 acini
What is the function of the interstitial tissue of the lung?
Provides a supporting framework for the airways, vessels and alveolar airspaces
What are the two types of interstitial tissue in the lungs?
Parenchymal (in the alveolar wall and surrounding small vessels and lymphatics where gas exchange occurs)
Non-parenchymal (in the pleura, interlobular septa and surrounding the large vessels and airways, where there is no gas exchange)
What medications/irradiations can cause interstitial lung disease?
- Nitrofurantonin
- Amiodarone
- Antineoplastic agents
Radiation therapy for cancer can cause…
lung injury
What is always on the differential diagnosis of interstitial lung diseases?
Treatment-related lung disease
Describe pathological patterns of treatment-related lung disease
The patterns overlap with idopathic ILDs and sometimes have mixed pattern
What is sarcoidosis?
It is a systemic disorder of unknown origin characterized by non-caseating granulomas in multiple organs (lungs, cardiac, liver, kidneys, brain).
90% of patients also have pulmonary manifestations.
What are pulmonary manifestations of sarcoidosis?
- Small nodules in a perilymphatic distribution
- Upper and middle zone predominance
- Lymphadenopathy
-DDx: Silicosis, Tuberculosis
Describe the histologic pattern of sarcoidosis
- Small non-necrotizing granulomas
- Follow bronchovascular bundles and lymphatics (pleura and intralobular septae)
- Can be in vessels
Describe the granulomas seen in sarcoidosis
- well-circumscribed
- epithelioid histiocytes and occasional giant cells
- little amounts of inflammatory cells (“naked” granulomas)
- VERY rarely, but may show some necrosis
