Unit 3 Day 6 (Tue 4/28) Flashcards
Primary Physiologic Abnormalities in Restrictive Lung Disease
TLC
Restriction
- hard to inhale
- affects inhalation work only
Obstruction
- hard to exhale
- inc. resistive work- both inspiration and expiration
Diseases/Processes That Lead to Restrictive Physiology
Restrictive Physiology Due to inc. in Elastic Recoil:
- inflammation or scarring may expand the interstitium and reduce compliance
- pulmonary edema
- surfactant depletion
- any alveolar filling process
- ARDS (acute respiratory distress syndrome)
- pneumonia
- cardiac pulmonary edema
Restrictive Physiology Due to Chest Wall Disease:
- pleural effusion
- asbestos-related pleural plaque
- kyphoscoliosis
Two features distinguish restrictive lung disease from restrictive physiology (chest wall restriction):
Slope of P-V curve is reduced in restrictive disease.
DLCO/VA is reduced in restrictive disease.
Both are preserved in restrictive physiology without restrictive disease.
Gas Exchange is _______ in Restrictive Lung Disease.
-Impaired Loss of alveolar surface area due to decreased lung volumes and decreased alveolar volume Diffusion limitation Restrictive chest wall diseases generally do not cause gas exchange problems
Acute Restrictive Processes
Pulmonary edema
ARDS/DAD
Pneumonia
Pleural effusion
Chronic Restrictive Processes
ILD - interstitial lung
diseases
Pleural fibrosis / plaques
Pleural effusion
Mixed Obstructive an Restrictive Disease
Must have reduced lung volumes AND reduced airflow (FEV1/FVC
Interstitial Lung Disease (ILD)
Heterogeneous group of disorders characterized by a combination of inflammation or scarring
Classified by etiology and pattern
ILD Presentation
- Dyspnea with exertion, cough
- Subacute to insidious timing
- Restrictive PFTs with decreased DLCO
- Abnormal lung imaging
- Variable prognosis; specific diagnoses matter!
ILD Diagnosis
-clinical-radiographic-pathologic diagnosis:
• Clinical info: associated diseases, exposures, drugs, lab testing
• Radiographic pattern on HRCT
• Pathologic pattern on surgical lung biopsy
ILD Physical Exam
Auscultation: end- inspiratory “velcro-like” crackles
Digital clubbing in advanced cases.
Joint and skin exam is important in identifying coexistent (causative?) collagen vascular disease.
ILD Treatment
- Remove offending exposure if possible
- Immunosuppressive therapy – Depends on type and etiology
- IPF: nintedanib, pirfenidone • Oxygen
- Transplantation
Idiopathic Pulmonary Fibrosis
IPF is a scarring lung disease with a pattern of injury of usual interstitial pneumonia (UIP).
Etiology is idiopathic.
(There are known causes for the same UIP pattern of injury).
Disease of older patients ( > 6th decade)
Associated with tobacco use
Cough, DOE, fatigue
Physical exam: Basilar predominant “velcro-crackles.” Digital clubbing in advanced cases.
Median survival from diagnosis is 2-3 years
Imaging: Peripheral and basilar predominant reticulation, traction bronchiectasis, honeycombing, and a paucity of ground glass infiltrate.
Path: Spatially and temporally heterogeneous fibrosis with fibroblast foci and juxtaposition of fibrotic and normal lung.
Pirfenidone and nintedanib were approved to treat IPF in Fall 2014.
Nonspecific Interstitial Pneumonia (NSIP)
NSIP presents similarly to other ILD
May be idiopathic, collagen vascular disease- related (RA, Sjögren’s, scleroderma, myositis), fibrotic HP, or drug-related.
More likely to be female; younger.
Prognosis is better than UIP/IPF, and collagen vascular-related may have better prognosis than idiopathic.
Responds to anti-inflammatory therapy
Radiographic – basilar predominant reticular abnormality with volume loss, traction bronchiectasis. Frequent ground glass opacity. Rare honeycombing.
Path: temporally homogeneous fibrosis with varying degrees of inflammation and fibrosis.
Smoking Related ILD
Respiratory bronchiolitis-ILD
Desquamative interstitial pneumonia (DIP)
These two diagnoses exist on a spectrum
Relatively rare compared to other IIP
Smoking cessation is key
Pulmonary Langerhans Cell Histiocytosis
Smoking Related ILD- Pulmonary Langerhans Cell Histiocytosis (PLCH)
Young smokers Imaging: cysts and nodules Upper lobe predominant Mixed PFTs PTX common 15% extrapulm dz—including bone lesions, pituitary involvement Treatment is smoking cessation
Organizing Pneumonia
Subacute to chronic presentation
Noninfectious pneumonia
Imaging shows ground glass and consolidation that may be migratory
Path: organizing pneumonia
Plugs of granulation tissue and
fibrosis distal to bronchioles
Very steroid responsive, but requires 6-12 months.
Relapses with rapid steroid withdrawal.
Eosinophilic Pneumonia
Acute eosinophilic pneumonia
- Mimics ARDS
- Often results in acute respiratory failure
- Diagnosed by BAL showing eosinophils
- Resolves with steroids
Chronic eosinophilic pneumonia -Subacute onset -Associated with asthma -Peripheral eosinophilia common -“Photographic negative of pulmonary edema” -Also diagnosed by BAL -Treated with steroids
Lymphangioleiomyomatosis (LAM)
Cystic lung disease exclusively of young women
Mutation in tuberous sclerosis gene 1 or 2
Peribronchovascular proliferation of smooth muscle cells
Cysts and nodules
Spontaneous pneumothorax and
chylothorax common
Obstructive pattern on PFTs
Renal tumors (angiomyolipomas)
Potential treatment with mTOR inhibitors (sirolimus)
Sarcoidosis
Abnormal CXR in up to 90%
Lymphadenopathy is common
Fibrosis may develop in up to 20%
Airway involvement in up to half
May have restrictive, obstructive or mixed PFTs
Cough, chest pain or wheezing
Presents before 40 y.o.
Commonly affects northern European descent; can affect
any race/ethnicity
More common in African Americans than white Americans
more likely to be severe and progressive
• Diagnosis is based on clinical findings and confirmed with tissue demonstrating granulomas
• Treatment is often not necessary
• Progressive disease is treated with steroids and cytotoxic drugs
