Pathology of Restrictive Pulmonary Disease Flashcards
Definition of chronic interstitial/restrictive lung diseases
group of diseases characterized by dyspnea and reduced TLC and often involving the interstitium
What is a microscopic hallmark of disease progression of restrictive lung disease
honeycomb lung
What does the pulmonary interstitial comprised of?
-BM of the endothelial and epithelial cells, collagen fibers, elastic tissue, and fibroblasts
What are the ‘fibrosing’ RLDs?
- idiopathic pulmonary fibrosis
- Collagen vascular disease-associated
- Pneumoconioses
- Drug/radiation pneumonitis
What are the ‘granulomatous’ RLDs?
- sarcoidosis
- hypersensitivity pneumonitis
What causes idiopathic pulmonary fibrosis (IPF) (aka usual intersitital pneumonia pattern HISTOLOGICALLY)?
repeat cycles of injury by an unidentified agent resulting in diffuse fibrosis and inflammation (via TGF-B) resulting in ‘amputation’ of distal airways that, when healing, combine alveoli
How does IPF present?
insidious dyspnea on exertion and progressive dry cough (usually need lung transplant eventually- treatment not effective)
How is the prognosis for IPF?
poor
What are some of the gross findings of IPF?
patchy interstitial fibrosis and lower lobe sub pleural distribution with intervening areas of normal lung
Another set of diseases that can cause lung fibrosis are the Collagen vascular disease-associated. Name some.
- Rheumatoid arthritis
- Scleroderma
- Mixed CT diseases
- Sjogren’s syndrome
A person with usual interstitial pneumonia may have what disease?
rheumatoid arthritis
Collagen vascular disease-associated lung disease has the exact same UIP pattern seen in ____
IPF. Need clinical history
What are some hallmarks of UIP?
- fibroblastic foci
- bronchi epithelium metaplasia
- lymphocytic infiltrate
Describe crytogenic organizing pneumonia (COP).
INTRAALVEOLAR (i.e. where the fibroblastic foci are) rather than an interstitial process with organizing CT in bronchioles, alveolar ducts, and alveoli
T or F. The organizing CT is all of the same age in COP and the underlying architecture is preserved
T. Different from IUP
Is COP responsive to steroids?
Yes, good prognosis
What is the average age of onset of UIP? COP?
UIP-60s
COP-50s
Onset of UIP? COP?
UIP- insidious
COP-acute
Which has a worse mortality rate, COP or UIP?
UIP (68%) to COP (10%). COP has a great response to steroids and a good change of full recovery
What are Pneumoconiosis?
non-neoplastic lung reaction to chronically inhaled dusts (coal, silica, asbestos, berylliosis)
What happens in pneumoconiosis?
particles reach alveoli and are encased by macrophages (so it cant be destroyed) and transported to respiratory bronchioles. Released into tissue when macrophages die, and the particles remain in the lump in foci mostly at the division of the large vessels, under the pleura, and in the hilar lymph nodes
Describe simple coal works pneumoconiosis (CWP)
- little or no pulmonary dysfunction
- predominantly in the upper lobe nodules and macules
What is the composition of the macules seen in simple CWP?
accumulations of dust adjacent to respiratory bronchioles and dilated alveoli
What is the composition of the nodules seen in simple CWP?
carbon-laden macrophages with collagen
Describe complicated coal works pneumoconiosis (CWP)
-lung function compromised after several years of simple CWP and get black scare of pigment and dense collagen
Complicated CWP is associated with ______.
rheumatoid arthritis
What causes silicosis?
inhalation of silica from sandblasters, mine workers, stone cutting that progresses to nodular fibrosis predominantly in the upper lobes and hilar nodes
How does the nodular fibrosis come about in silicosis?
silica ingestion by macrophages use release of fibrogenic mediators
Silicosis increases susceptibility to ___
TB.
What things can asbestos exposure cause?
- diffuse pleural fibrosis
- benign pleural effusions
- pleural plaques (no asbestos fibers in these lesions)
- parenchymal interstitial fibrosis (Asbestosis)
How does asbestos related disease present?
slowly progressive dyspnea after long, heavy exposure due to fibrosis to respiratory bronchioles and alveolar ducts after macrophages try to clear it
What category of drugs is known to cause pulmonary fibrosis?
chemotherapy drugs (and radiation)
Beryllium exposure increases risk of ____
lung cancer
Beryllium exposure is associated with ____ granulomas in hillier lymph nodes and the lung
non-caseating
How does sarcoidosis present?
insidious onset of SOB
T or F. Sarcoidosis responds well to steroids
T.
How would BAL present?
Increased CD4:CD8 (greater than 2.5) due to increased CD4+
What causes hypersensitivity pneumonitis (HP)?
lugn disorder due to prolonged exposure to inhaled organic dust. Chronic form is a type IV (delayed T cell mediated) hypersensitivity
Acute hypersensitivity pneumonitis is a type ___ hypersensitivity.
III
T or F. Removal of environmental antigen can prevent progression to fibrosis
T.
What are the categories of causes of HP?
- thermophilic bacterial antigens
- animal proteins
- fungal antigens
What are some thermophilic bacterial antigens causes of HP?
- Farmer’s lung
- Mushroom worker’s lung
- Humidifier lung
- Hot tub lung
What are some animal proteins causes of HP?
- Bird fancier’s lung
- Mollusk shell HP
What are some fungal antigens causes of HP?
- Malt worker’s lung
- Cheese washer’s lung
- Paprika splitter’s lung
- Maple bark stripper’s lung
Features of HP
- airway centered interstitial lymphocytic inflammation
- loosely formed granulomas and interstitial fibrosis
- organizing pneumonia
T or F. Eosinophils are a feature of HP
F.
How can you distinguish HP from IPF/UIP?
HP is more upper lobe
The majority of patients with DIP are ___
smokers
Pulmonary Langerhans Cell Histiocytosis
- rare (95% smokers)
- mostly get better after quitting
- those with BRAF mutations affect more than one tissue
Pulmonary Langerhans Cell Histiocytosis
positive for Langerin, S-100, CD1a and negative for CD68
cells have a ‘coffee bean’ appearance
What happens in Pulmonary alveolar proteinosis?
defect in GM-CSF or macrophages results in accumulation of surfactant in alveolar spaces (very pink)
Buzzword with Pneumocystis jirovecii?
crushed ping pong ball appearance in alveolar spaces
