Restrictive lung diseases Flashcards
what are some common features of restrictive lung disease in terms of PFTs?
problem with lung filling. if you can’t fill the lung, total lung capacity will decrease. the forced vital capacity will be down (you can’t bring air in, so not that much can come out). the FEV1 will also be down. However, the FEV1:FVC ratio is INCREASED (>80)
What is the most common cause of restrictive disease? Other causes?
interstitial fibrosis. difficulty with exchange AND filling. However, these may also arise from chest wall abnormalities (obesity) or from muscular effort (polio, myasthenia gravis)
What is idiopathic pulmonary fibrosis?
fibrosis of the lung intersitium
cyclic lung injury with cyclical healing. TGF-beta is a key mediator of healing. TGF beta and IL-10 are important for healing. injured pneumocytes release TGF-beta- causes fibrosis
what are secondary causes of interstial fibrosis that must be excluded to diagnose a patient with idiopathic pulmonary fibrosis?
bleomycin, amiodarone, methotrexate, busulfan (used for CML), radiation
What are the pneumoconioses? Causes (general)? What cells are involved?
fibrosis d/t an occupational exposure that activates fibrosis.
pretty much requires chronic exposure to small particles that are fibrogenic.
fibrosis is mediated by MACROPHAGES?
Coal workers pneumoconioses: exposure, findings, associations. which lobe?
carbon gets in. you get massive fibrosis of the lung. this may cause “black lung,” and shrunken lung. especially effects the upper lobes.
associated with rhuematoid arthritis (Caplan syndrome)
What is seen with mild exposure to carbon?
build up of carbon in macrophages- anthracosis. this is not clinically significant.
may also be seen in the hilar lymph nodes.
What is silicosis? Findings, associations. which lobe?
exposure to silica. seen in sandblasters, silica miners. silica impairs phagolysosomal formation. may see eggshell calcification of hilar lymph nodes. this is the ONLY pneumoconiosis that increases the risk for TB; also associated with an increased risk of bronchogenic cancer. see fibrotic nodules in upper lobes of lung.
Berylliosis: exposure, findings, associations
seen in beryllium miners and workers in aerospace inducstry. causes noncaseating granulomas in the lung, hilar lymph nodes, and systemic organs. don’t confuse with sarcoidosis. there is an increased risk for lung cancer.
asbestosis: exposure, complications, pathology. What lobes are affected?
seen in construction, plumbers, and shipyard workers.
casues fibrosis of lung/pluera, or cancer of lung/pleura.
look for asbestos bodies: long, rod shaped particle that classically has little brown iron beads. (aka ferruginous body). ivory white calcified pleural plaques are pathognomonic. affects the lower lobes
sarcoidosis: path findings, what structures are often invovled
systemic disease characterized by noncaseating granulomas in multiple organs. probably d/t CD4 positive T cells. may also see astroid bodies. often involve the hilar lymph node and the lung.
what are other organs inovled in sarcoidosis?
uvea, skin, salivary and lacrimal glands, almost any tissue.
clinical features of sarcoid?
cough, dyspnea, elevated serum ACE, hypercalcemia (this is because the granulomas have 1-alphahydroxylase activity- this can activate vitamin D). this is true of ANY disease with lots of noncaseating granulomas.
What is hypersensitivity pneumonitis? What kind of hypersensitivity reaction? Who is the typical patient
patient is exposed to an antigen. there is a granulomatous reaction to the antigen. eosinophils will be present. this is a mixed type III/IV hypersensitivity often seen in farmers and those exposed to birds.
What are clinical manifestations of hypersensitivity pneumonitis?
the patient presents with fever, cough, and dyspnea hours after the exposure. this resolves with removal. however, chronic exposure can cause interstitial fibrosis
