SM 163a - Intro to DPLD Flashcards
What are the common findings of ILD on chest x-ray?
- Reticular or reticulonodular pattern of fibrosis
- Usually prominent in lung bases
- Hilar lymphadenopathy
- Calcified pleural plaques
What patterns are shown in this HRCT?
What disease is this consistent with?
- Ground glass opacities
- Reticulation
- Traction bronchiectasis
Consistent with Nonspecific Interstitial Pneumonia (NSIP)
What defines interstitial lung disease (aka diffuse parenchymal lung disease)?
Damage to the alveolar wall, including the interstitium
- May also involve the alveolar airspace and small conducting airways
- Causes a restrictive defect in lung function
Serologic testing for auto-antibodies is most helpful in diagnosing which forms of ILD?
Specific diagnoses of connective tissues disease - associated ILD
What is necessary to diagnose sarcoidosis?
All of the following:
- Compatible history
- Decreased cutaneous delayed-type hypersensitivity reactions
- Increase in Th1/Th17 responses at sites of disease
- Characteristic physical exam, labs, and imaging
- Biopsy of lung, lymph node, or extrapulmonary site that shows non-caseating, epithelioid, granulomatous inflammation without evidence of infection or other cause of the granuloma
What is sarcoidosis?
A multi-system disorder of unknown cause characterized by non-caseating granulomatous inflammation in affected tissues
- May be triggered by exogenous agents in genetically susceptible individuals
- Involves the lungs in 90% of cases
Which of the following cell types is most susceptible to injury?
- Type I alveolar epithelial cells
- Type II alveolar epithelial cells
- Pulmonary fibroblasts
a. Type I alveolar epithelial cells
These cells make up most of the structural components in the alveolar wall.
What autoimmune diseases are associated with ILD?
Sarcoidosis
Hypersensitivity pneumonitis
Scleroderma
Lupus
Which three ILDs can be diagnosed via bronchoscopy with transbronchial biopsy?
Sarcoidosis
Lymphangitic carcinoma
Pulmonary infections
(The sample is too small to diagnose others)
What cells will be abnormally abundant in the bronchoalveolar lavage of a patient with hypersensitivity pneumonitis?
Lymphocytes
What pattern is shown in this HRCT?
What disease might this indicate?
UIP pattern
- Lower-lobe, peripheral predominant reticular opacities
- Traction bronchiectasis
- Peripheral honeycombing
The UIP pattern is consistent with IPF. However, we cannot diagnose IPF unless we know for sure it is idiopathic
Describe the HRCT findings of acute/subacute Hypersensitivity Pneumonitis
- Ground glass opacities
- Centrilobular
- Usually upper-lobe predominant
- Signs of air-trapping
What is the usual treatment for pneumoconiosis or hypersensitivity penumonitis?
- Remove offending exposure
- Corticosteroids
- Anti-inflammatory agents
What are the symptoms of ILD?
Usually nonspecific
- Dyspnea
- Cough
- Fatigue
- Weight loss
- Fever
- Non-pulmonary symptoms/signs of connective tissue disease
What is the interstitium?
The potential space between alveolar epithelium and capillary endothelium
This x-ray shows a _________ pattern, characteristic of _________.
This X-ray shows a reticular** pattern, characteristic of **interstitial lung diseases.
Specifically, chronic fibrosing IIPs (this one specifically shows IPF)
Which HRCT shows a reticular opacity and which shows a nodular opacity?
Which diseases do these opacities represent?
What HRCT findings are consistent with IPF?
UIP pattern
- Reticular opacities
- Peripheral, lower-lobe predominant
- Traction bronchiectasis
- Enlargement of the airway due to abnormality in the parenchyma surrounding the airway
- Honeycombing
Describe the presentation of subacute/chronic Hypersenitivity Pneumonitis (HP)
- Dyspnea, cough, fatigue, weight loss
- Caused by prolonged or repeated antigen exposure
- Usually without history of acute HP
- Can progress to pulmonary fibrosis with respiratory failure
What are the 4 major causes of granulomatous ILD?
- Infectous
- TB, non-TB mycobacterium, endemic fungal infections
- Sarcoidosis
- Berylliosis
- Hypersensitivity pneumonitis (HP)
What abormality is shown in this HRCT?
Which disease is this consistent with?
Ground glass opacities
Seen in acute/subacute hypersensitivity pneumonitis (HP)
What causes hypersensitivity pneumonitis?
An immunologic response to inhaled organic dusts
What are the 3 major causes of granulomatous DPLDs?
- Sarcoidosis
- Hypersensitivity pneumonitis (HP)
- Infectious disorders
- TB, non-TB mycobacterium, Fungal
How are the granulomas in sarcoidosis and hypersensitivity pneumonitis different?
- Sarcoidosis
- Tightly packed
- Well-formed
- Hypersensitivity pneumonitis
- Loosly packed
- Not as well-formed
What HRCT findings are consistent with nonspecific interstitial pneumonia (NSIP)?
- Ground glass opacities
- Reticulaiton
- Traction bronchiectasis
Describe the biopsy of a patient with hypersensitivity pneumonitis
- Inflammation centered around small airways
- Many lymphocytes
- Poorly formed, non-caseating granulomas peribrochially
- Areas of normal and abnormal lung may be present
What are the 4 major causes of DPLDs classified as “DPLDs of known cause and origin?”
- Pneumoconiosis - caused by occupational exposure to inorganic dusts
- Hypersensitivity pneumonitis - an immunologic response to inhaled organic dusts
- Reactions to chemicals, drugs, radiation, and toxic gases
-
Systemic Disease
- Connective tissue disease
- Granulomatous (also classified as a granulomatous DPLD)
What causes pneumoconiosis?
Occupational exposure to inorganic dusts
(Asbestos, silica)
Describe the HRCT findings associated with sarcoidosis
- Nodular opacities
- Upper or mid lung zone predominant
- “tree in bud” opacities
- Nodules wtih hilar and mediastinal lymphadenopathy
What abnormality is shown in this HRCT?
Which disease is this consistent with?
Nodular opacities
Seen in sarcoidosis
What are the 3 subdivisions of DPLDs classified as “idiopathic interstitial pneumonias (IIPs)?”
- Chronic fibrosising IIPs
- Idiopathic pulmonary fibrosis (IPF)
- Idiopathic nonspecific interstitial pneumonia (NSIP)
- Smoking-related IIPs
- Respiratory bronchiolitis ILD (RB-ILD)
- Desquamative interstitial pneumonia (DIP)
- Acute/subacute IIPs
- Cryptogenic organizing pneumonia (COP)
- Acute interstitial pneumonia (AIP)
Which type of pulmonary function abnormality is most common in ILD?
- Obstructive defect
- Restrictive defect
- Mixed obstructive and restrictive defect
b. Restrictive defect
Which Major IIP Is Most Common?
- Acute interstitial pneumonia (AIP)
- Cryptogenic organizing pneumonia (COP)
- Desquamative interstitial pneumonia (DIP)
- Idiopathic pulmonary fibrosis (IPF)
- Nonspecific interstitial pneumonia (NSIP)
- Respiratory bronchiolitis-interstitial lung disease (RB-ILD)
d. Idiopathic pulmonary fibrosis (IPF)
What changes would you expect to see on pulmonary function testing in a patient with ILD?
- Restrictive defect
- Decreased diffusing capacity
- May see obstructive defect or mixed restrictive/obstructive defect in sarcoidosis or hypersensitivity pneumonitis
- Hypoxemia upon exertion
- And eventually at rest
This x-ray shows a _________ pattern, characteristic of _________.
This x-ray shows an alveolar** pattern, characteristic of **pulmonary alveolar proteinosis.
Which ILD does not respond to corticosteriods?
IPF
Use antifibrotic agents instead (pirfenidone, nintedanin)
Describe the presentation of acute hypersensitivity pneumonitis (HP)
Dyspnea, fever, chills, malaise within hours of exposure
Resolution in 1-a few days, if there is no repeat exposure
What is the treatment for sarcoidosis?
Is it effective?
Corticosteroids + immunosuppressive therapies
Treatment does not always work; in ~1/3 of patients, the granulomatous inflammation progresses to fibrosis and impaired lung function
- Possible drugs
- Methotrexate
- Azathioprine
- Mycophenolate
- Leflunomide
- TNF inhibitors (infliximab, adalimumab)
This x-ray shows a _________ pattern, characteristic of _________.
This x-ray shows a nodular** pattern, characteristic of **sarcoidosis (an ILD).
What are the physical exam findings associated with ILD?
- Inspiratory crackles
- Digital clubbing
- Pulmonary HTN, right heart failure
- Cyanosis
What pattern does this HRCT show?
What disease is this consistent with?
Honeycomb cysts
Indicate the presence of fibrosis
This HRCT is consistent with IPF (advanced/end-stage)
List the 4 major categories of ILD (aka DPLD)
- DPLDs of known cause and origin
- Idiopathic interstitial pneumonia (IIPs)
- Granulomatous DPLDs
- Other
What kind of cell is circled?
Which ILD is this consistent with?
Multi-nucleated giant cell
Consistent with sarcoidosis
How is hypersensitivity pneumonitis treated?
- Remove offending agent (if identified)
- Corticosteroids
- Immunosuppresants
- Azathioprine
- Mycophenolate
What pathology is shown here?
Which disease is this consistent with?
Non-caseating granulomas
Characteristic of sarcoidosis
Describe the interstitial patterns on chest x-ray.
What lung disease do they indicate?
Interstitial pattern indicates some from of ILD
- Reticular intertitial pattern
- Seen in IPF
- Nodular interstitial pattern
- Seen in sarcoidosis
- May be reticulonodular
Describe the HRCT findings of chronic hypersensitivity pneumonitis (HP)
- Reticular opacities
- Traction bronchiectasis
- Honeycombing (indicates fibrosis)
- Not as peripherally-concentrated as UIP pattern in IPF
Disease is predominant in upper and middle lobes
What are the PFT characteristics of a restrictive lung defect?
- Decreased lung volumes
- Normal or increased FEV1/FVC
- Decreased lung compliance
- Decreased DLCO
