Restrictive Lung Disease Flashcards
4 most common ILD in young adults
IPF, pulmonary langerhans cell histiocytosis, eosinophilic granulomatosis w/ polyangiitis, sarcoidosis
3 requirments for normal respiratory physiology (mechanics)
compliant chest wall, normal muscle strength, compliant lungs
3 mechanisms for RLDs (think about 3 requirements for normal physiology)
abnormalities of chest wall (obesity, kyphoscoliosis)
weakness of respiratory muscles (polio, myasthenia gravis)
abnormalities of lung parenchyma (sarcoidosis, IPF)
ILD effect on PFTs
TLC, FRC, RV all lowered- increased elastic recoil
muscle weakness effect on PFTs
lower TLC, normal FRC (no effect on chest expansion or lung recoil), RV elevated (cant expel as much air forcefully)
obesity effect on PFTs
low TLC, low FRC (increased chest expansion), normal RV
hallmark is lower FRC
two pathological types of ILD
cellular and fibrotic
ILD impact on spirometry
reduced FVC, reduced FEV1, normal to high FEV/FVC ratio (no obstruction)
ILD impact on Hb sat
increases the time required to saturate RBC Hb for a given amount of alveolar O2, uses up the reserve time
ILD and cor pulmonale
reduced compliance leads to higher resistance for RV, eventual right heart failure
common disease that mimics ILD- how is it different
CHF, different b/c the diffuse infiltrates are from increased hydrostatic pressure and pulm edema rather than cellular/fibrotic infiltrates in the alveolar interstitium
on CXR- infiltrates tend to be in lower lungs, cardiomegaly, kerley lines
3 possible known etiology ILDs
pneumoconiosis- inhaled dust
hypersensitivity pneumonities- inhaled organic antigens
iatrogenic- radiation or drugs (bleomycin, amiodarone, methotrexate)
risk factors for silicosis
occupational exposure: mining, masonry, pottery, jewelers, quarry, foundry
silicosis on CXR
upper lobe nodular infiltrate
eggshell calcification of hilar lymph nodes
risk factors for asbestosis
shipyard, roofing, factory
asbestos on CXR and histopath and gross
lower lobe diffuse infiltrate on CXR
ferruginous bodies on histology (rod like fibers coated w/ iron)
pleural plaques grossly
CXR of coal workers pneumoconiosis
mainly upper lobes, nodular pattern that can progress to diffuse
utility of high resolution chest CT
helps Dx ILDs when not detectable on CXR, specific Dx, distinguish b/w active inflammation and fibrosis
most likely Dx w/ consolidation and air bronchograms
bacterial pneumonia
differentiate ground glass and consolidation
ground glass- can see blood vessels through infiltrate, common w/ active inflammation ILDs, cardiogenic pulm edema
cant w/ consolidation, common w/ bacteiral pneumonia
what does ground glass mean w/ suspected ILD
active inflammation vs fibrosis
most common cause of this is cardiogenic pulm edema
5 possible causes of diffuses alveolar hemorrhage
goodpasture, microscopic polyangiitis, granulomatosis w/ polyangiitis, lupus, cocaine
most common idiopathic interstitial pneumonia
IPF, presents w/ UIP
physical exam finding and CXR for IPF
traction bronchiectasis- the fibrosis pulls the airways apart causing dilation
clubbing from polycythemia
pathophys of IPF
cell injury and death in the lungs causes fibroblast proliferation and coagulation, eventual collagen deposition
mediated by TGF beta, KGF, CTGF, PDGF
3 cells involved in sarcoidosis
histiocytes, dendritic cells w/i non caseating granuloma
lymphs surrounding, Th1 CD4 interact w/ APCs via MHC complexes
cytokine profile in sarcoidosis
INF-gamma, IL 2, IL12
similar to bacteria, fungi, viral
two possible antigens that provoke sarcoid
mycobacteria, propionibactera
lofgrens syndrome
combo of hilar adenopathy and erythema nodosum seen in sarcoid pts, usually self resolves
stage 1 of pulm sarcoidosis
adenopathy, normal lungs
stage 2 pulm sarcoid
abnormal nodes and lung
stage 3 sarcoid
abnormal lung, normal nodes
stage 4 sarcoid
fibrosis of lung parenchyma, usually upper lobe w/ retraction of the hila
needed for sarcoid Dx
granulomas (non caseating), exclude other causes (TB, fungi, cancer)
lupus pernio
cutaneous sarcoid, associated w/ chronic fibrotic lung disease
enzymes produced by sarcoid granulomas
1 alpha hydroxylase (increases serum calcium via calcitriol, more absorption and reabsorption)
ACE
Tx for sarcoid
either let self resolve
corticosteroids
