Restrictive Interstitial Lung Disease Flashcards
Common Presentation
Dyspnea
Dry, Nonproductive Cough
Inspiratory Crackles on Exam (except Sarcoidosis)
May or may not have digital clubbing
Common Chest X-ray and CT Findings
nodular oppacties - diffuse white spots
reticular opacities - irregular spider webs that represent scarring
honeycombs (CT) - alveoli are broken and surrounded by thick scar tissue, limiting the passage of gasses across the alveolar-capillary barrier
traction bronchiectasis (CT) - too much negative pressure pulls tissue away from bronchioles
FVC
low
FEV1/FVC
normal to high
DLCO
low
TLC
low
Common Pathophysiology
injury and damage occurs to the alveolar epithelial or capillary endothelial cells leading to inflammation (alveolitis) and eventually fibrosis
the inflammation and scarring limits the passage of gases across the alveolar-capillary barrier
Lungs with interstitial lung disease …
show areas of fibrosis (irreversibly enlarged, damaged bronchioles and distorted alveoli) that alternate with areas of normal lung
the areas of fibrosis between the alveoli greatly decreases the gas exchange, reducing oxygen transferred to the bloodstream
honeycombing results – clustered cystic air spaces
Idiopathic Pulmonary Fibrosis
also called Usual Interstitial Pneumonia
fibrotic scarring of the lung interstitium of unknown cause
Idiopathic Pulmonary Fibrosis: Epidemiology
men
55-60 yo
white
Idiopathic Pulmonary Fibrosis: Signs and Symptoms
insidious onset of dry, hacking cough
SOB
inspiratory crackles on exam
slow onset; may seem normal to patient
Idiopathic Pulmonary Fibrosis: Characteristic Histologic Pattern
alternating areas of normal lung, interstitial inflammation, fibroblast focial, and honeycomb change (+/-)
Idiopathic Pulmonary Fibrosis: Chest X-Ray
reticular opacities with a basilar predominance (lower lobes)
Idiopathic Pulmonary Fibrosis: CT
basilar and subpleural areas of reticular changes, honeycombing, and traction bronchiectasis
Idiopathic Pulmonary Fibrosis: Diagnosis
must rule out other insterstitial diseases in order to be truly idiopathic
can be made on H&P and imaging alone as long as all features are present
may require tissue pathology via Bronchoalveolar Lavage or Transbronchial Biopsy or Surgical Lung Biopsy
Idiopathic Pulmonary Fibrosis: Treatment
none; lung transplant is definitive with a 50% 5 year survival rate
Sarcoidosis
a multisystem granulomatous disorder of unknown etiology
multisystem inflammatory disorder characterized by noncaseating granuloma formation
Sarcoidosis: Epidemiology
geographical and familial clusters
10-20 per 100,000
African Americans
Female
20-30 yo
Sarcoidosis: Signs and Symptoms
pulmonary findings in 90%: onset of dry hacking cough and shortness of breath can be subacute (weeks to months) or chronic (months to years)
NO inspiratory crackles
Imaging: reticular opacities are in the middle and upper lungs
hilar adenopathy
extrapulmonary findings
Sarcoidosis: Extrapulmonary Findings
may have fatigue, malaise, fever, or weight loss
skin lesions
cervical lymphadenopathy
visual changes, dry eyes
dry mouth, parotid swelling
joint pain and swelling
muscle weakness
hepatomegaly and tenderness
Sarcoidosis: Diagnosis
based on H&P (no historical features indicative of other similar presenting disorders) and imaging findings
MUST have tissue pathology that shows noncaseating granulomas
CBC to rule out lymphomas
Sarcoidosis: Treatment
glucocorticoids (Prednisone)
immunosuppressive therapy if ineffective (Methotrexate)
Pneumoconiosis
occupational lung disease secondary to inhalation of inorganic dusts
a group of chronic fibrotic lung diseases that result from inhalation of inorganic dusts typically associated with specific occupations
treatment is supportive
Coal Miners Lung Disease: Pathophysiology
coal dust is ingested by macrophages, which then become coal macules that show as 2-5 mm radio-opaque nodules on chest x-ray
Coal Miners Lung Disease: Chest X-Ray
2-5 mm radio-opaque nodules that are primarily in the upper lung fields in “simple”
may become more widespread in “complicated coal worker’s pneumoconiosis” with progressive massive fibrosis
Coal Miners Lung Disease: Treatment
supportive care; no other treatment is shown to help; prevent further exposure
Asbestos Pneumoconiosis
secondary to inhalation of asbestos fibers, which contain fibrous magnesium silicate
Who is most at risk for developing Asbestos Pneumoconiosis?
asbestos mining and milling workers are most at risk, but also people doing insulation work, shipbuilding, construction, pipe fitting, and textile work
Asbestos Pneumoconiosis: Symptoms
dry, nonproductive cough; dyspnea; and inspiratory crackles that presents decades after exposure
Asbestos Pneumoconiosis Imaging
reticular and small nodular opacities in the lower lung field
calcified pleural plaques in the lower lungs
pleural effusions
Asbestos Pneumoconiosis: Pathology Lab
pathology is not necessary but can aid diagnosis by identifying asbestos fibers and ferruginous bodies
Asbestos Pneumoconiosis: Complications
respiratory failure for a minority of patients
Malignancy: bronchogenic adenocarcinoma, malignant mesothelioma, concomitant smoking increases risk
Asbestos Pneumoconiosis: Treatment
supportive and preventative; O2
Silicosis Pneumoconiosis
secondary to inhalation of crystalline silica (SiO2) in quartz, grant, or sandstone
can be acute or chronic
Who is most at risk for developing Silicosis Pneumoconiosis?
occupations at risk include mining, quarrying, drilling, potters, masonry, and sandblasting
Acute Silicosis Pneumoconiosis
rare; after exposure to high concentrations of crystalline silica
symptoms begin within a few weeks to years
appears like chronic silicosis on radiograph, but shows sooner
poor prognosis: progresses to complicated and frequently respiratory failure
less than four year survival rate from onset of symptoms
Chronic Silicosis Pneumoconiosis
often decades after cessation of job associated with exposure
includes Simple Silicosis, which can progress to Complicated Silicosis (Progressive Massive Fibrosis)
can be asymptomatic and only noted on chest x-ray
insidious onset of cough and dyspnea with inspiratory crackles on exam
Silicosis Pneumoconiosis: Imaging
Simple Silicosis appears as innumerable, small, rounded opacities (<10mm) in the dorsal, upper lung fields
Complicated Silicosis shows larger nodules (>1cm) that evolve into conglomerate masses
the small nodules of simple have coalesced
conglomerate masses can appear like malignancies
Berylliosis Pneumoconiosis
a chronic, immunologically mediated, granulomatous disease caused by exposure to beryllium
your body makes an antibody to beryllium, and the immune response leads to disease
Beryllium
a metal used in a number of industrial applications
Who is at most risk for developing Berylliosis Pneumoconiosis?
occupations at risk include metal and metal allow machine shops, electronics manufacture and assembly, defense industry, beryllium extraction, automotive industry, computer industry, aerospace industry (more often)
Berylliosis Pneumoconiosis: Symptoms
insidious onset of dry, nonproductive cough; shortness of breath; crackles in the lungs on exam
inhalation causes pulmonary pathology, but skin contact can also cause cutaneous nodules
cutaneous nodules are on exposed areas of skin and smaller than those in Sarcoidosis
onset of exposure to symptoms varies from 3 months to 30 years
Berylliosis Pneumoconiosis: Imaging
varies, but more common in the upper lung fields
Berylliosis Pneumoconiosis: Special Testing
Beryllium Lymphocyte Proliferation Test (BeLPT)
blood test, low sensitivity, high specificity
repeat negative or borderline
two negatives is a ‘negative;
also perform Bronchoalveolar Lavage (BAL) effluent
Berylliosis Pneumoconiosis: Tissue Pathology
shows noncaseating granulomas
Berylliosis Pneumoconiosis: Management
mild disease or Beryllium sensitization but no frank Berylliosis: None
with onset of bothersome dyspnea or decrease in lung volumes: Prednisone chronically
if fail glucocorticoids then may try Methotrexate or other immunosuppressive agents but no clear evidence showing efficacy
Berylliosis Pneumoconiosis: Prognosis
course is variable; may live chronically on glucocorticoids
some patients experience progressive deterioration of lung function and development of pulmonary fibrosis
no increased risk of cancer
Hypersensitivity Pneumonitis
an immunologic reaction to an inhaled organic antigen that is often animal or plant related, such as agricultural dusts, bioaerosols, reactive chemical species
requires initial exposure to sensitize the immune system; subsequent exposures can then result in disease
Occupations and hobbies most at risk for Hypersensitivity Pneumonitis are related to….
farming, bird and poultry handling, and ventilation and water-related contamination
Farming Environmental Source and Causative Agent related to Hypersensitivity Pneumonitis
moldy hay, grain, and silage
thermophilic actinomycetes
Poultry Handling Environmental Source and Causative Agent related to Hypersensitivity Pneumonitis
parakeets, budgerigars, pigeons
droppings, feathers, serum proteins
Ventilation and Water-Related Environmental Sources and Causative Agents related to Hypersensitivity Pneumonitis
humidifier fever – thermoactinomyces
hot-tub lung – myobacterium complex
lifeguard lung – endotoxin from pool-water sprays
Acute Hypersensitivity Pneumonitis: Symptoms
abrupt onset (w/in 4-6 hrs) of fever, chills, malaise, nausea, cough, chest tightness, dyspnea; exam with basilar crackles and tachypnea
Acute Hypersensitivity Pneumonitis: Imaging
CXR frequently normal
Acute Hypersensitivity Pneumonitis can be confused with?
potentially confused with a viral or bacterial infection and given antibiotics
Acute Hypersensitivity Pneumonitis: Treatment
remove from environment where exposure occurred and not return
symptoms subside within 12hrs to several days.
disease may recur with re-exposure
Subacute Hypersensitivity Pneumonitis: Symptoms
gradual development of productive cough, dyspnea, fatigue, anorexia and weight loss; exam with tachypnea and diffuse crackles
Subacute Hypersensitivity Pneumonitis: PFTs
restrictive pattern and decreased DLCO
Subacute Hypersensitivity Pneumonitis: Imaging
CXR normal to micronodular or reticular opacities; HRCT with diffuse micronodules
Subacute Hypersensitivity Pneumonitis: BAL
Bronchalveolar Lavage (BAL) often performed and shows marked lymphocytosis
Subacute Hypersensitivity Pneumonitis: Tissue Pathology
shows noncaseating granulomas
Subacute Hypersensitivity Pneumonitis: Treatment
removal from exposure; glucocorticoids may be required.
improvement in symptoms and function takes weeks to months
Chronic Hypersensitivity Pneumonitis: Symptoms
insidious onset of cough, dyspnea, fatigue, weight loss
Chronic Hypersensitivity Pneumonitis: Imaging
similar to IPF; differentiation from IPF may be difficult
Chronic Hypersensitivity Pneumonitis: BAL
Bronchoalveolar Lavage (BAL) is often necessary - low CD4 to CD8 ratio
Chronic Hypersensitivity Pneumonitis: Tissue Pathology
noncaseating granulomas, destruction of alveoli, bronchiolitis obliterans
Chronic Hypersensitivity Pneumonitis: Treatment
chronic glucocorticoids
removal from exposure still necessary but doesn’t help as much
Byssinosis
an obstructive, asthma-like, disorder caused by inhalation of cotton fibers
presents with chest tightness, cough, wheezing and dyspnea
usually worse on Mondays or first day back after a break/vacation
if left untreated and without job change, could lead to chronic bronchitis/COPD
Sillo-filler’s Disease
toxic lung injury due to nitrogen dioxide inhalation
bacterial conversion of nitrates in fresh grains produces N02; his gas is heavier than air and accumulates in silos
inhalation of large amounts causes toxic injury to airways and alveoli
leads to increased tissue permeability → pulmonary edema
Sillo-filler’s Disease: Symptoms
dyspnea, cough, crackles on exam, occasionally wheezing as well
Sillo-filler’s Disease: Treatment
glucocorticoids ASAP to prevent progression to bronchiolitis obliterans, a common late complication.
