Gomez - Interstitial Diseases Flashcards
What type of appearance do infiltrative X-rays have?
Reticulonodular
Ground glass
What is another name for Idiopathic Pulmonary Fibrosis?
Usual interstitial pneumonia
Describe Idiopathic Pulmonary Fibrosis
Repeated bouts of inflammation lead to scarring of the lung
Cause of inflammation is largely unknown
Scarring causes increased thickness of diffusion barrier, inhibiting effectiveness of gas exchange
Very patchy
What does caveolin do?
Where is it found?
What is it inhibited by?
Inhibits deposition of collagen and ECM
Found in fibroblasts
TGF-β1
What are the typical sx of IPF?
Dyspnea
Cough
Hypoxemia with cyanosis
Clubbing of digits
What is the typical affected age group by IPF?
What is the median survival?
Typically affects middle-aged individuals
Median survival 3 yrs
What is the pathological progression of IPF?
Repeated bouts of inflammation causes scarring
Healing/scarring cycle causes patcy fibrosis
Over time, more and more areas of lung become involved
End result: honeycomb lung
What part of the lung does IPF affect first?
Usually affects sub-pleural region first, then progresses to involve more and more of lung
Describe Nonspecific Interstitial Pneumonia
Appears to be more limited than IPF
Not a result of repeated bouts of inflammation
Better prognosis than IPF
Will see inflammatory cells in interstitium
What is organizing pneumonia?
Replacement of tissue in the alveolar space by fibrous connective tissue
What are Masson bodies?
Balls of fibrous connective tissue that fill alveoli in cryptogenic organizing pneumonia
Describe cryptogenic organizing pneumonia
A pneumonia of unknown etiology in which fibrous connective tissue fills the alveolar spaces
No interstitial fibrosis, so no progression to honeycomb lung
How are systemic conditions related to lung diseases? What are some of them?
Autoimmune diseases can have lung involvement
Rheumatoid arthritis
Scleroderma
SLE
Sjögren synrome
Polymyositis/dermatomyositis
Mixed connective tissue disorder
What process is pictured here? What can it be a sign of?
Follicular bronchiolitis
Can indicate rheumatoid arthritis
What is Caplan syndrome?
Combination of rheumatoid arthritis and pneumoconiosis
Pneumoconiosis is disease caused by inhalation of something
What sized particles are most dangerous to lungs?
1-5 microns
What factors contribute to particulates entering lung tissue?
Amount/volume
Size, shape, and buoyancy of particles
Solubility/cytotoxicity
Concomitant irritants
Is a pt exposed to asbestos more likely to develop mesothelioma or carcinoma of the lung?
Carcinoma of the lung
What is Farmer’s lung?
Exposure to moldy hay
What are the three stages of Coal Worker’s Pneumoconiosis (CWP)?
Asymptomatic anthracosis (coal dust inhalation)
Simple CWP
Complicated CWP
What is anthracosis?
Deposition of black pigment in lung and adjacent lymph nodes
From coal dust
Describe simple coal worker’s pneumoconiosis
Usually benign
Will see some macules and nodules that appear on X-ray
Pt has no difficulty breathing
Describe complicated coal worker’s pneumoconiosis
Symptomatic form of CWP, often associated with progressive massive fibrosis (PMF)
Extensive scarring
Can result in pulmonary HTN and cor pulmonale
What is depicted in this image?
Anthracosis
What will make coal worker’s pneumonia significantly worse?
Concomitant exposure to silica
Who is at greatest risk for developing silicosis?
Sandblasters
Miners
Demolition crews
Describe the process of silicosis
Slowly progressive disease that takes decades to develop
Slica particle taken into lungs
Particle ingested by MΦ
MΦ killed by particle, causing it to be released along with inflammatory mediators
Particle can be taken up by other MΦ and process repeats
What does silicosis look like on X-ray?
Egg shell calcification
What conditions are related to asbestos exposure?
Pleural effusion
Pleural plaques or diffuse pleural fibrosis
Asbestosis
Lung CA
Laryngeal CA
Mesothelioma
What are the two types of asbestos?
Chrysotile (more common in industry); wavy and larger particle, not as carcinogenic
Amphibole (more harmful form)
What is shown in this image? Why is it brown?
Asbestos body
Brown because of iron content
Do pleural plaques contain asbestos bodies?
No asbestos bodies present in pleural plaques
What do pleural plaques look like on X-ray?
Pleural plaques appear as masses
Need to do multiple images or use another modality (CT or MR) to confirm presence
What is Farmer’s lung caused by?
Moldy hay carrying Micropolysporia faeni
What causes bagassosis?
Moldy pressed cane sugar colonized by thermophilic actinomycetes
What causes humidfier lung?
Cool mist humidifiers colonized by thermophilic actinomycetes or Aureobasidium pullulans
What causes bird fancier’s lung/pigeon breeder’s lung?
Serum proteins in pigeon droppings
What is desquamative interstitial pneumonia?
Associated with smoking
A bunch of alveolar MΦs eating up all the junk that’s been inhaled
What are Birbeck granules?
Found within Langerhans cells
Trilaminar in appearance with dilation at the end
Sometimes resemble tennis racquets, depending upon plane of section
Describe Respiratory Bronchiolitis-associated Interstitial Lung DIsease (RBILD)
Commonly found in smokers
MΦ infiltrates in bronchioles
Can find peribronchiolar fibrosis
What markers do Langerhans cells typically express?
CD1a, CD207 are the most common
Can also see S-100
What are the characteristics of sarcoidosis?
Formation of numerous non-caseating granulomas
Can occur almost anywhere in the body
More common in women than men
More common in African Americans than Whites
What testing can be abnormal in pts with sarcoidosis?
Why does this happen?
Pts can have anergy to PPD or Candida antigens
Due to immune system working so hard to address the sarcoidosis that it will not respond to other antigens
What happens to angiotensin converting enzyme in sarcoidosis?
ACE level will be elevated in pts with sarcoidosis
Also elevated in pts with leprosy
What is Löeffler’s syndrome?
Transient acute pulmonary eosinophilia from any cause
What will be seen histologically in pts with pulmonary alveolar proteinosis?
Accumulation of acellular surfactant in the alveolar and bronchiolar spaces
How would you treat autoimmune pulmonary alveolar proteinosis?
With granulocyte/macrophage colony stimulating factor (GM-CSF)
