large number os conditions that involve the parenchyma -implies inflammatory-fibrotic infiltration of the alveolar walls
pathophysiology of ILD
decreased/low lung compliance -if the lung is compliant that it is unable to adapt to the environment restrictive pattern on PFT's (reduced TLC) reduced diffusion capacity hypoxemia- initially with exercise, later at rest
what "defines" restrictive lung disease
a low TLC (<80% predicted)
if someone has obstructive and restrictive how would that be described?
a reduced FEV-1% and a reduced TLC ex- coal miners lung
what else is seen in ILD?
decreased diffusion capacity, DLCO will be low
What are the results on PFT for restrictive?
FEV-1 - decreased FVC - decreased FEV-1%- normal or increased TLC - decreased FRC - decreased
What are the results on PFT for obstructive?
FEV-1 - decreased FVC - normal or decreased FEV-1%- <70% TLC - normal FRC - normal or increased
Characteristics of obstructive:
normal or elastic lungs normal or low elastic recoil high airway resistance low expiratory flow rates
Characteristics of restrictive:
Stiff lungs high elastic recoil normal airway resistance high expiratory flow rates
what is the clinical presentation os ILD?
dyspnea on exertion, non-productive cough tachypnea, bibasilar inspiratory dray crackles
may have: clubbing, cyanosis, signs of cor pulmonale
-characterized by development of non-caseating granulomas in one or more organs -cause is unknown, but may be form of hypersensitivity reaction -typically occurs in young females, balacks -may involve any organ (resp more common)
what are lab studies for sarcoid
skin tests for allergies hypercalcemia elevated LFT elevated ACE levels
how is sarcoidosis dx?
-biopsies of affected organ that is demonstrating non-caseating granulomas -must exclude other granulomatous diseases -increased CD4/CD8 ratio
what does a CXR for sacroidosis look like?
BHA parenchymal infiltrates -upper/mid lung zone predominance distortion and fibrosis
stage 0 of sarcoid on CXR
stage 1 of sarcoid on CXR
stage 2 of sarcoid on CXR
BHA plus interstitial infiltrates
stage 3 of sarcoid on CXR
interstitial infiltrates with no BHA
stage 4 of sarcoid on CXR
advanced fibrosis/honey combing
sarcoidosis signs associated with worse prognosis
higher CXR stage at initial diagnosis african american onset >40 y/o longer duration of symptoms (>6 months) absence of E. nodosum (Lofgren's syndorme) splenomegaly involvement of more than 3 organ systems
what are some tx's for sarcoid?
1st line- corticosteroids with a slow taper 2nd line- anti-inflammatory/cyctotoxic agents
what are definite indications for tx of sarcoid?
involvement of cardiac, eye, CNA, symptomatic hypercalcemia, symptomatic lung disease with decreasing PFT, extensive skin lesions
establishing hx of asbestos exposure and pleuropulmonary manifestation is key -occupation commonly associated w/ exposure
what are some manifestations of asbestos?
Asbestosis Lung cancer benign asbestos pleural effusion mesothelioma pleural plaques
what is "asbestosis"?
ILD with onset 20 years or more after exposure -no specific/effective therapy no role for corticosteroids
what is mesothelioma
highly fatal malignancy occurring 30-40 years after onset of asbestos exposure - no effective therapy -unrelated to pleural plaques. CA of pleura of the lungs
what are pleural plaques
benign pleural thickenings that are a marker of asbestos exposure
what is hypersensitivity pneumonitis?
extrinsic allergic alveolitis -immune disease of lung due to repeated/prolonged exposure to variety of organic dusts in a susceptible individual -pathology=mononuclear cell infiltration/ loosely formed granulomas (no biopsy needed) -CXR=reticulo-nodular, infiltrates (may normalize between episodes)
what are the 3 forms of hypersensitivity pneumonitis?