clinical features and management of restrictive lung disease Flashcards
define restriction
forced vital capacity <80% of normal
what is used as a marker of restriction
vital capacity
spirometry is key
what are the causes of restriction
lungs pleura nerve/muscle bone other
lung causes of restriction
interstitial lung disease:
idiopathic pulmonary fibrosis
sarcoidosis
hypersensitivity pneumonitis
pleural causes of restriction
pleural effusion
pneumothorax
pleural thickening e.g. from TB (calcification)
skeletal causes of restriction
kyphoscoliosis
ankylosing spondylitis
thoracoplasty
rib fractures - pain
what is thoracoplasty
TB patients used to have ribs reduced/removed at the top to reduce lung volume in order to treat the TB before abx were developed
TB is aerobic so by reducing the lung volume it reduced the ability of the TB to grow
muscular causes of restriction
amyotrophic lateral sclerosis - neurological cause of restrictive pattern to breathing
sub-diaphragmatic causes of restriction
obesity
pregnancy
is restrictive pattern of lung function always due to lung disease
NO
Where is the interstitium
space between the epithelium of the alveolus and the endothelium of the capillary
1-2 cells thick over which gas exchange occurs
what are interstitial lung diseases
> 200 disease causing thickening of the interstitium and can result in pulmonary fibrosis
top 3 ILDs
sarcoidosis
idiopathic pulmonary fibrosis
hypersensitivity pneumonitis
what is sarcoidosis
multisystem granulomatous disease of unknown cause
histological hallmark is non-caseating granuloma
just because there is a granuloma doesnt mean there is sarcoidosis
what is erythema nodosum
bruising rash
well known association with sarcoidosis
lumps on the shins tend to be sore
where are granulomas found in sarcoidosis
skin lesions
often locate to areas of trauma e.g. scars
who gets sarcoidosis
adults <40
f>m
world-wide
how is sarcoidosis investigated
Hx and exam
CXR
stage I sarcoidosis disease on CXR
nodes only
lymphadenopathy and enlarged blood vessels
stage II sarcoidosis disease on CXR
snowstorm shadowing
nodes and lung parenchymal involvement
stage III sarcoidosis disease
fibrosis
stage IV sarcoidosis disease
wrecked lung
irreversible w/o transplant
how is sarcoidosis investigated
pulmonary function tests - can’t be done in isolation
bloods - lower lymphocyte conc in peripheral blood, concentrated in lungs
urinalysis - check for protein or blood, differentiate from vasculitis
ECG - cardiac sarcoidosis can be fatal
TB skin test - granulomas can also be TB
eye exam - check for posterior uveitis, anterior uveitis is bright red
why are smokers less likely to get sarcoid
suppression of lymphocyte response