Restrictive Diseases Flashcards
What are Restrictive Diseases characterized by?
Restricted filling of the lung (problem filling the lung)
What do Restrictive Diseases show on spirometry?
Dec. TLC
Dec. FEV1
Dec. (ALOT) FVC
FEV1:FVC ratio is Increased!
What is normal FEV1:FVC ratio? What is this ratio in restrictive diseases?
80%
Restrictive diseases are >80%
What most commonly causes Restrictive Diseases?
Interstitial diseases of he lung
What may also cause Restrictive Disease?
Chest wall abnormalities (such as massive obesity)
What is the pathogenesis behind interstitial diseases of the lung?
- Fibrosis of interstitium
- Thickening of the barrier
- Hard to open airway/sacs
What are the four main Restrictive Diseases?
- Idiopathic Pulmonary Fibrosis
- Pneumoconioses
- Sarcoidosis
- Hypersensitivity Pneumonitis
What is Idiopathic Pulmonary Fibrosis?
Fibrosis of lung interstitium
What is the etiology of Pulmonary Fibrosis?
Unknown
What is Idiopathic Pulmonary Fibrosis likely related to?
Cyclical lung injury
What induces fibrosis in Idiopathic Pulmonary Fibrosis?
TGF-beta from injured pneumocytes induces fibrosis.
What are secondary causes of Interstitial Fibrosis?
- Drugs (Bleomycin and Amiodarone)
- Radiation therapy
What are two symptoms of Idiopathic Pulmonary Fibrosis?
- Progressive dyspnea
2. Cough
What is seen in Idiopathic Pulmonary Fibrosis on Lung CT?
Fibrosis
-> Initially seen in sub pleural patches but eventually results in diffuse fibrosis with end-stage ‘honeycomb’ lung
What is the treatment for Idiopathic Pulmonary Fibrosis?
Lung transplantation
What is Pneumoconiosis?
Interstitial fibrosis due to occupational lung exposure.
What is required for Pneumoconiosis to occur?
Chronic exposure to small particles that are fibrogenic
-Particles small enough that they can get into distal lung and induce fibrosis (through macrophages)
What causes the fibrosis in Pneumoconiosis?
Alveolar macrophages engulf foreign particles and induce fibrosis, trying to ‘wall off’ the foreign substance.
What exposure causes Coal Workers’ Pneumoconiosis?
Carbon dust; seen in coal miners
What does massive exposure to carbon dust (coal miners) lead to?
Diffuse fibrosis (‘black lung’) and shrunken lung.
What is Coal Workers’ Pneumoconiosis associated with?
Rheumatoid Arthritis (Caplan syndrome)
What is Anthracosis?
Collections of carbon-laden macrophages.
What causes Anthracosis?
Mild exposure to carbon (e.g. pollution)
Is Anthracosis clinically significant?
NO
What exposure causes Silicosis?
Silica
What populations is Silicosis seen in?
Sandblasters and silica miners
What is seen in the lungs of patients with Silicosis?
Fibrotic nodules in upper lobes of the lung
What are patients with Silicosis at increased risk for?
TB
What does silica impair in the lung?
Silica impairs phagolysosome formation by macrophages
What exposure causes Berylliosis?
Beryllium
In what populations is Berylliosis seen in?
Beryllium miners and workers in the aerospace industry (NASA)
What pathologic findings are seen in Berylliosis?
Noncaseating granulomas in the lung, hilar lymph nodes and systemic organs.
What are the pathological findings in Berylliosis similar to?
Sarcoidosis
What are patients with Berylliosis at an increased risk for?
Lung cancer!
What exposure causes Asbestosis?
Asbestos fibers
What populations is Asbestosis seen in?
Construction workers, Plumbers, Shipyard workers
What type of cancer is more common in Asbestos exposed individuals?
Lung carcinoma is more common than mesothelioma.
What pathologic findings are associated with Asbestosis?
Fibrosis of lung and pleura (plaques) with increased risk of lung carcinoma and mesothelioma.
What findings confirm exposure to asbestos in lung lesions?
Lesions containing long, golden-brown fibers with associated iron (asbestos bodies)
What is Sarcoidosis?
Systemic disease characterized by noncaseating granulomas in multiple organs.
What does Noncaseating mean?
All cells in granuloma are alive
What is the most common site for noncaseating granulomas in Sarcoidosis?
Lungs & hilar lymph nodes
What population is Sarcoidosis most commonly seen in?
African American Females
What is the Etiology of Sarcoidosis?
Unknown
What is the proposed pathogenesis of Sarcoidosis?
Likely due to CD4+ helper T-cell response to an unknown antigen.
What do granulomas most commonly involve in Sarcoidosis? What do they lead to?
Hilar lymph nodes and lung.
Restrictive lung disease.
What is often seen in the granulomas of Sarcoidosis?
Epitheliod histiocytes & giant cells
What is often seen within the giant cells of Sarcoidosis granulomas?
Stellate inclusions (‘asteroid bodies’)
What are other commonly involved tissues in Sarcoidosis?
- Uvea (uveitis)
- Skin (cutaneous nodules or erythema nodosum)
- Salivary and lacrimal glands (mimics Sjogren syndrome)
- Almost any tissue can be involved
What are the common symptoms of Sarcoidosis?
- Dyspnea
- Cough (most common presenting symptom)
What do you see in the serum of Sarcoidosis?
Elevated ACE
What does the noncaseating granuloma in Sarcoidosis cause in the serum?
Hypercalcemia
How does noncaseating granulomas lead to Hypercalcemia?
1-alpha hydroxylase activity of epithelioid histiocytes converts vitamin D to its active form
What is the treatment for Sarcoidosis?
Steroids. Often resolves spontaneously without treatment.
What is Hypersensitivity Pneumonitis?
Granulomatous reaction to inhaled organic antigens
What will you see on a slide of Hypersensitivity Pneumonitis?
Granulomas and Eosinophils
What is an example of an organic antigen that causes Hypersensitivity Pneumonitis?
Pigeon Breeder’s Lung
What does Hypersensitivity Pneumonitis present with?
-Fever
-Cough
-Dyspnea
. . .hours after exposure
When does Hypersensitivity Pneumonitis resolve?
With removal of the exposure.
What does chronic exposure to the inhaled organic antigen lead to in Hypersensitivity Pneumonitis?
Interstitial Fibrosis
