SM_163a: Introduction to DPLD Flashcards
What is interstitial lung disease (also called diffuse parenchymal lung disease)?
Diseases of alveolar wall, including including interstitium, which is the potential space between the basement membranes of the alveolar epithelium and capillary endothelium
(may also involve alveolar space and small airways)
Diverse disorders grouped together b/c of shared clinical, radiographic, physiologic, and pathologic features that have many possible causes
(specific diagnosis challenging)
What components of a history are important to ask for ILD/DPLD?
- Occupation
- Hobbies
- Pets
- Drugs
- Smoking / vaping
- Family Hx
- Other symptoms / illnesses
________ is the lung cell type most susceptible to injury
Type I alveolar epithelial cells is the lung cell type most susceptible to injury
Sarcoidosis is most common in _________
Sarcoidosis is most common in African Americans
Describe the clinical presentation of ILD/DPLD
- Symptoms:
- Physical findings:
- Other:
Clinical presentation of ILD/DPLD
- Symptoms: insidious exertional dyspnea (breathlessness), non-productive cough
- Physical findings: fine end-inspiratory crackles (Velcro rales), digital clubbing (IPF), cyanosis, signs of cor pulmonale (increased P2, RV lift, right-sided S3, JVD, edema(
- Other: symptoms and/or signs of systemic illness
Most common symptom of ILD/DPLD is ________
Most common symptom of ILD/DPLD is exertional dyspnea of insidious onset
(non-productive cough is second most common)
Describe the x-ray manifestations of ILD/DPLD
- Interstitial pattern: reticular (fine lines), nodular, or reticulo-nodular
- Alveolar pattern: diffuse, patchy
(10% of people are normal at initial presentation)
Idiopathic pulmonary fibrosis shows a ________ interstitial pattern on chest x-ray
Idiopathic pulmonary fibrosis shows a reticular interstitial pattern on chest x-ray
Sarcoidosis shows a ________ interstitial pattern on chest x-ray
Sarcoidosis shows a nodular interstitial pattern on chest x-ray
Pulmonary alveolar proteinosis shows a(n) _______ pattern on chest x-ray
Pulmonary alveolar proteinosis shows an alveolar pattern on chest x-ray
Describe the high resolution computed tomography manifestations of ILD/DPLP
- Reticular opacities
- Nodular opacities
- Ground glass opacities
- Traction bronchiectasis
- Honeycomb cysts
(HRCT is more sensitive than plain CXR or routine CT, specific patterns can narrow DDx)
Scleroderma shows ________ on high-resolution CT
Scleroderma shows reticular opacities on high-resolution CT
Sarcoidosis shows ________ on high-resolution CT
Sarcoidosis shows nodular opacities on high-resolution CT
Hypersensitivity pneumonitis shows ________ on high-resolution CT
Hypersensitivity pneumonitis shows ground glass opacities on high-resolution CT
Nonspecific interstitial pneumonia shows ________, ________, and ________ on high-resolution CT
Nonspecific interstitial pneumonia shows ground glass opacities, reticulation, and traction bronchiectasis on high-resolution CT
This high resolution CT shows the _______ and _______ of idiopathic pulmonary fibrosis
This high resolution CT shows the reticular opacities and traction bronchiectasis of idiopathic pulmonary fibrosis
This CT shows the ________ of idiopathic pulmonary fibrosis
This CT shows the honeycomb cyst of idiopathic pulmonary fibrosis
______ is the type of pulmonary function abnormality most common in ILD
Restrictive defect is the type of pulmonary function abnormality most common in ILD
Describe the morphology of the obstruction and restriction curves on spirometry
- Obstruction: airways are narrowed or collapsible when person forcefully exhales -> reduced rate at which air can be exhaled -> more gradual slope
- Restrictive: amount of air patient gets in/out of lung is reduced but flow rate stays the same (FEV1 reduced but FEV1/FVC is not reduced)
Describe the pulmonary physiology of ILD
- PFTs: restrictive defect most common
- Decreased lung volumes (TLC, FRC, RV)
- Normal or increased FEV1/FVC
- Pressure-volume curve shows decreased lung compliance
- DLCO is reduced
- Mixed restrictive + obstructive defects also occur
- Arterial blood gas: increased A-a gradient, decreased PaO2
- Exercise testing: abnormal earlier than in resting studies
- Increased RR, decreased VT, increased VD/VT, increased A-a gradient, decreased PaO2
Classification of IIPs
- Major:
- Rare:
- Other:
Classification of IIPs
- Major: idiopathic pulmonary fibrosis, idiopathic nonspecific interstitial pneumonia, respiratory bronchiolitis interstitial lung disease, desquamative interstitial pneumonia, cryptogenic organizing pneumonia, acute interstitial pneumonia
- Rare: idiopathic lymphocytic interstitial pneumonia, idiopathic pleuroparenchymal fibroelastosis
- Other: idiopathic pneumonia w/ autoimmune features
A way to categorize major IIPs is into ______, ______, and ______
A way to categorize major IIPs is into chronic fibrosis IP, smoking related IP, and acute/subacute IP
_______ is the most common major IIP
Idiopathic pulmonary fibrosis is the most common major IIP
Granulomas can be _______ or _______
Granulomas can be infectious or non-infectious
Infectious: tuberculosis, nontuberculosis mycobacterial infection, endemic fungal infections (histoplasmosis, blastomycosis, coccidiodomycosis)
Non-infectious: sarcoidosis, berylliosis, hypersensitivity pneumonitis
Sarcoidosis is a ______ disorder of ______ cause most commonly affecting the ______
Sarcoidosis is a multi-system disorder of unknown cause most commonly affecting the lung
(also affects skin, eyes, nose/sinuses, liver, heart CNS)
Sarcoidosis most commonly presents as ______ and ______
Sarcoidosis most commonly presents as ILD and thoracic LN enlargement
Sarcoidosis histology can be described as _______
Sarcoidosis histology can be described as non-caseating epithelioid granulomas
(no evidence of infection or foreign body)
Sarcoidosis immunological features include ______ and ______
Sarcoidosis immunological features include decreased cutaneous DTH and increased TH1/TH17 responses at the sites of disease
The clinical course of sarcoidosis is ______
Sarcoidosis responds to ______
The clinical course of sarcoidosis is variable
Sarcoidosis responds to steroids
What is hypersensitivity pneumonitis?
Immune-mediated lung disease that can be triggered by a long list of inhaled antigens from microorganisms, animals, plants, chemicals
- Both innate and adaptive immune mechanisms play a role
- Precipitating IgG antibodies directed at the offending antigen are typically present (but antibodies may be present w/o disease)
Describe the clinical presentation of hypersensitivity pneumonitis
- Acute:
- Subacute:
- Chronic:
Hypersensitivity pneumonitis
- Acute: fever, chills, malaise, dyspnea 4-8 hours after exposure
- Subacute: symptoms gradually develop over weeks
- Chronic: insidious onset of dyspnea, cough, fatigue, weight loss, and hypoxemia over months-years
Describe the diagnosis of hypersensitivity pneumonitis
- Detailed exposure history critical
- High resolution CT
- Acute/subacute disease: ground glass opacities, mosaic attenuation pattern, centrilobular nodules
- Chronic disease: reticulation, traction bronchiectasis, honeycombing
- PFTs: restrictive, obstructive, or mixed defects
- Serum antibody testing
- Bronchoalveolar lavage: lymphocytosis
- Lung biopsy: patchy peribronchial inflammatory infiltrate w/ lymphocyte predominance, loose/poorly formed granulomas, fibrotic change in advanced disease
- Determination of causative exposure often not possible
This is ______ hypersensitivity pneumonitis
This is subacute hypersensitivity pneumonitis
This is ______ hypersensitivity pneumonitis
This is chronic hypersensitivity pneumonitis
Describe the diagnostic considerations of ILD
- History, serologic studies, and HRCT pattern are critical and may suffice for confident clinical-radiologic diagnosis
- Bronchoscopic transbronchial biopsy: too small for diagnosis of most diseases except sarcoidosis, neoplasm, infection
- Surgical lung biopsy is gold standard in absence of confident clinical-radiologic diagnosis
Describe the treatment of ILD
- Pneumoconiosies (drug or toxin induces disease): termination of exposure
- Idiopathic pulmonary fibrosis: corticosteroids not effective, pirfenidone or nintedinib
- Non-specific interstitial pneumonia, CTD-ILD, IPAF: corticosteroids, mycophenolate, azathioprine, tacrolimus, rituximab
- Sarcoidosis: corticosteroids; methotrexate, azathioprine, mycophenolate, leflunomide; TNF inhibitors (infliximab, adalimumab)
- Hypersensitivity pneumonitis: termination of exposure; corticosteroids, azathioprine, mycophenolate
- Supplemental oxygen, influenza and pneumococcal vaccination, pulmonary rehabilitation, lung transplantation
