Term
| what characterizes the pulmonary interstitial diseases? |
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Definition
| deposition of material such as fibrotic tissue in the intersitium between alveoli leading to chronic involvement of the pulmonary connective tisssue. the alveoli themselves may be involved if the disease progresses far enough |
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Term
| what is the pulmonary interstitium composed of? |
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Definition
| a basement membrane w/endothelial and epithelial cells, collagen, elastic tissue, proteoglycans, fibroblasts, some mast cells, and occasional lymphocytes and monocytes |
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Term
| what kind of pulmonary disease is usually associated with diffuse interstitial pulmonary disease? |
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Definition
| restrictive diseases - often featuring a reduction in CO2 diffusing capacity, lung volume and compliance |
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Term
| what would a CXR of a pt with diffuse interstitial pulmonary disease likely show? |
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Definition
| diffuse infiltration by small nodules, irregular lines or ground glass shadows |
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Term
| what are the clinicopathologic syndrome/specific histology categories that make up diffuse interstitial pulmonary disease? |
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Definition
| fibrosis, granulomatous, eosinophilic, smoking-related, and other |
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Term
| what are some of the diseases that can cause fibrosing pulmonary interstitial lung disease? |
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Definition
| usual interstitial pneumonia (IPF), nonspecific interstitial pneumonia, cryptogenic organizing pneumonia, association with collagen vascular disease, pneumoconiosis, drug reactions, and radiation pneumonitis |
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Term
| what are some of the diseases that can cause granulomatous pulmonary interstitial lung disease? |
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Definition
| sarcoidosis, hypersensitivity pneumonitis |
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Term
| what are some of the diseases that can cause smoking related pulmonary interstitial lung disease? |
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Definition
| desquamative interstitial pneumonia, respiratory bronchiolitis and associated interstitial lung disease |
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Term
| can pulmonary alveolar proteinosis (PAP)cause fibrosing pulmonary interstitial lung disease? what is this a disorder of? what does this appear as on CXR? histology? how do pts present? |
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Definition
| yes. this is *surfactant proteins in the alveoli, which appear as bilateral patchy asymmetric pulmonary opacification. histologically, PAP appears as *homogenous granular precipitate in the alveoli resulting in consolidation of large areas of the lung *w/minimal inflammatory rxn. the lungs are markedly heavy and pts present with *insidious resp difficulty *w/abundant sputum. they are also at risk of *developing secondary infections |
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Term
| what is the earliest manifestation of pulmonary intersitial disease? |
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Definition
| alveolitis w/accumulation on inflammatory and immune cells in the alveolar walls and spaces. the leukocytes distort the alveolar structures and their mediators injure the parenchymal cells - stimulating fibrosis, which gives rise to end stage fibrotic lung where alveoli are replaced by cystic spaces separated by thick bands of connective tissue interspersed w/inflammatory cells (results in a severely restrictive "honeycomb" lung which perfusion/ventilation are very difficult) |
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Term
| what is idiopathic pulmonary fibrosis? |
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Definition
| repeated bouts of acute lung injury by some unidentified agent that cause *exuberant fibroblastic proliferation, giving rise to fibroblastic foci (firm/rubbery areas) with frequent *subpleural/paraseptal distribution. the histologic pattern is termed *usual interstitial pneumonia. |
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Term
| what is the honeycomb fibrosis that idiopathic pulmonary fibrosis can result in? |
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Definition
| honeycomb fibrosis is the result of alveolar collapse w/formation of cystic spaces lined by *hyperplastic type II pneumocytes |
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Term
| what kind of inflammation/cell changes are seen in the fibrotic areas of idiopathic pulmonary fibrosis? can this affect vascular circulation? |
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Definition
| with IPF, there is mild to moderate inflammation in the fibrotic areas w/foci of *squamous metaplasia (loss of ciliated columnar cells) and *smooth muscle hyperplasia. intimal fibrosis and medial thickening of the pulmonary arteries can also occur with IPF leading to *secondary pulmonary hypertensive changes |
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Term
| what is the difference between lungs affected by emphysema and idiopathic pulmonary fibrosis? |
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Definition
| lungs affected by emphysema are often puffy and over air filled, while lungs affected by idiopathic pulmonary fibrosis are generally hard - *it is not due to broken down alveoli |
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Term
| can the honeycomb lung the the end stage of several diseases? |
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Definition
| yes, w/IPF being one of them |
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Term
| what are the clinical features of idiopathic pulmonary fibrosis? |
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Definition
| IPF is marked by an insidious progression of dyspnea on exertion and dry cough. it is seen in pts usually 40-70 yrs old, progression is unpredictable and mean survival is < 3 yrs. the definitive tx is lung transplantation |
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Term
| what characterizes nonspecific interstitial pneumonia? |
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Definition
| this is a diffuse interstitial lung disease of unknown etiology where bx will fail to show specific features, there are 2 histologic patterns associated with it |
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Term
| what are the 2 histologic patterns seen with nonspecific interstitial pneumonia? |
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Definition
| cellular pattern: mild to moderate chronic interstitial inflammation w/lymphocytes and a few plasma cells (*better outcome*). fibrosing pattern: diffuse or patchy interstitial fibrosis, *no fibroblastic foci |
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Term
| what is the clinical course of nonspecific interstitial pneumonia? |
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Definition
| similar to IPF, features dyspnea/dry cough for several months and affects pts 45-55 yrs old |
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Term
| what is cryptogenic organizing pnemonia? |
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Definition
| COP, (also known as bronchiolitis obliterans organizing pneumonia) features cough and dyspnea and subpleural/peribronchial patchy consolidation. histologically, there are focal *polyploid plugs of loose organizing connective tisse in alveolar ducts which are all about the *same age. (no interstitial fibrosis/honeycomb lung). most pts need steroids to recover completely, but some will recover spontaneously |
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Term
| what collagen vascular diseases can lead to pulmonary disease? |
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Definition
| SLE, RA, and scleroderma all involve the lung. scleroderma (excessive collagen deposition in random areas): nonspecific interstitial pneumonia. RA: chronic pleuritis, interstitial pneumonitis/fibrosis, intrapulmonary rheumatoid nodules, and pulm HTN. SLE: patchy parenchymal infiltrates |
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Term
| what are drug induced lung diseases: |
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Definition
| bronchospasm (asthma/hypersensitivity), pulmonary edema (common w/opiate use), DAD, organizing pneumonia, interstitial fibrosis, and eosinophilic pneumonia |
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Term
| what drugs can lead to bronchospasm? |
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Definition
|
|
Term
| what drugs can lead to hypersensitivity pneumonitis? |
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Definition
| nitrofurantoin and methotrexate |
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Term
| what drugs can lead to pneumonitis and fibrosis? |
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Definition
|
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Term
| what is acute radiation pneumonitis? |
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Definition
| fever, dyspnea, and pleural effusion 1-6 mos after radiation therapy in 10-20% of pts treated |
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Term
| what is chronic radiation pneumonitis characterized by? |
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Definition
| lymphocytic alveolitis and pulmonary fibrosis |
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Term
| what are the granulomatous lung diseases that can lead to fibrosing pulmonary interstitial lung disease? |
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Definition
| sarcoidosis and hypersensitivity pneumonitis |
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Term
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Definition
| a systemic disease of unknown cause featuring noncaseating granulomas in many organs and tissues that can present w/various clinical symptoms including *bilateral hilar lymphadenopathy and eye/skin lesions. it is more common in african americans and women. |
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Term
| what is sarcoidosis a dx of? what may it mimic? what is thought to be its etiology? |
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Definition
| sarcoidosis is a dx of exclusion and may mimic mycobacterial/fungal infections as well as beryliosis. the etiology of sarcoidosis is thought to be related to pts with particular genetic predispositions being exposed to certain environmental antigens |
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Term
| what is the immunologic pathological process involved in sarcoidosis? |
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Definition
| there is intra-alveolar and interstitial accumulation of *TH1 CD4+ T cells in response to an unidentified antigen that then release IL-2+IFN, resulting in T cell expansion/macrophage activation which favors the recruitment of more T cells/monocytes which contributes to the formation of granulomas. TNF is also released at high levels by activated alveolar macrophages. |
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Term
| what are thought to be the genetic factors predisposing pts for sarcoidosis? |
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Definition
| HLA-A1 and B8 as well as familial and racial clustering of cases |
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Term
| what are thought to be the environmental factors predisposing pts for sarcoidosis? |
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Definition
| there is a tenuous connection of sarcoid to infectious agents and proposed microbes include mycobacteria and rickettsia species |
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Term
| what is the morphology of sarcoidosis? |
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Definition
| noncaseating granulomas composed of aggregates of giant cells w/little or no central necrosis. the chronic lesions may become enclosed by a fibrous rim which may be replaced by hyaline fibrous scars. there are *schaumann bodies, which are laminated concretions made of Ca++ and proteins, *asteroid bodies, which are stellate inclusions in giant cells -> these bodies however are not pathognomic for sardoiosis |
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Term
| what is the morphology of sarcoidosis in the lungs? |
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Definition
| small nodules may form primarily along the lymphatics, around blood vessels and bronchi |
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Term
| what characterizes lymph node involvement in sarcoidosis? |
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Definition
| the lymph nodes are involved in most cases of sarcoidosis, especially the hilar and mediastinal lymph nodes - which become discrete and sometimes calcified |
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Term
| is the spleen involved in many cases of sarcoidosis? liver? |
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Definition
| yes, in 3/4 of cases granulomas may coalesce in the spleen to form nodules. the liver is also often involved, especially around the portal triads |
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Term
| how is bone marrow affected in sarcoidosis? |
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Definition
| the phalangeal bones of the feet and hands form small circumscribed areas of bone resorption in the marrow cavity w/widening of the bone shafts+new bone formation on the outer surfaces |
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Term
| how is the skin affected in sarcoidosis? |
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Definition
| sarcoid skin lesions consist of nodules, erythematous plaques or scaling flat lesions, mucous membranes of the oral cavity and laryne are also involved |
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Term
| how are the eyes and lacrimal glands affected in sarcoidosis? |
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Definition
| if the lacrimal glands are affected = iritis, corneal opacities and glaucoma w/possible total vision loss |
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Term
| what is the name of the syndrome when salivary/lacrimal glands are involved with sardoidosis? |
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Definition
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|
Term
| what is the effect of sarcoid involvement of the muscle (sarcoid myositis)? |
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Definition
| muscle weakness, aches, tenderness and fatigue |
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Term
| can cardiac involvement of sarcoidosis be lethal? |
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Definition
|
|
Term
| can renal/CNS involvement w/sarcoidosis occur? |
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Definition
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Term
| what is the clinical course of pts with sarcoidosis involving the lungs? |
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Definition
| variable: SOB, chest pain, cough, hemoptysis, fever, fatigue, anorexia, night sweats. it is an unpredictable course with exacerbations and remission of symptoms. pts may succumb to pulm fibrosis or cor pulmonale and CNS/cardiac lesions may be fatal |
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Term
| what is the most common cause of hemoptysis in the US? |
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Definition
| chronic bronchitis (TB worldwide) |
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Term
| what is hypersensitivity pneumonitis? |
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Definition
| a spectrum of immunogologically mediated interstitial lung disorders cause by intense, often prolonged exposure to inhaled inorganic dusts, occupational antigens, and organic dusts containing spores of bacteria/fungi/animal proteins/bacterial products. affected individuals have an *abnormal sensitivity to the antigen which involves the alveoli and the hypersensitivity pneumonitis may progress to *chronic fibrotic lung disease if the antigen is not removed. |
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Term
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Definition
| hypersensitivity pneumonitis due to dusts from warm hay which contain spors of actinomycetes |
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Term
| what is pidgeon breeder's lung? |
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Definition
| hypersensitivity pneumonitis due to exposure to proteins from bird droppings/feathers |
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Term
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Definition
| hypersensitivity pneumonitis due to thermophilic bacteria in heated water reservoirs |
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Term
| is hypersensitivity pneumonitis an immunologically mediated disease? |
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Definition
| yes. if a bronchoalveolar lavage is performed, increased levels of proinflammatory chemokines/T cells will be seen along with complement and Ig in the vessel walls. most pts have antibodies in their serum suggestive of type III hypersensitivity and if there are noncaseating granulomas, this indicates a type IV hypersensitivity reaction. |
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Term
| what is the morphology of hypersensitivity pneumonitis that would be seen in a lung bx? |
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Definition
| there would be interstitial pneumonitis with infiltration of lymphocytes, plasma cells, and macrophages - often leading to interstitial fibrosis and obliterative bronchiolits. noncaseating granuomas are seen in 2/3 of pts. |
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Term
| what are the clinical features of hypersensitivity pneumonitis? |
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Definition
| varied: acute attacks may occur 4-6 hrs after exposure, with recurring episodes of fever, dyspnea, cough, and leukocytosis. on CXR: diffuse nodular infiltrates. PFT: restrictive pulmonary disorder |
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Term
| what may happen in hypersensitivity pneumonitis if exposure continues? |
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Definition
| progressive pulmonary failure with cyanosis |
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Term
| what is pulmonary eosinophilia? what are the 5 kinds? |
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Definition
| pulmonary eosinophila encapsulates several clinical and pathologic entities w/infiltration of eosinophils featuring increased eosinophil attractants such as IL5. these diseases are of immunologic origin and include: acute eosinophilic pneumonia w/respiratory failure, simple pulmonary eosinophila (*loeffler syndrome*), tropical eosinophila (due to infection by microfilariae), secondary eosinophila, and idiopathic chronic eosinophilic pneumonia |
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Term
| what is acute eosinophilic pneumonia? how does it present clinically? CXR? bronchoalveolar laveage? tx? |
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Definition
| an acute illness of unknown cause, characterized by a rapid onset w/fever, dysnpea, and hypoxemic respiratory failure. CXR: diffuse infiltrates. bronchoalveolar lavage: fluid contains more than 25% eosinophils. acute eosinophilic pneumonia responds to corticosteroids. |
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Term
| what is simple pulmonary eosinophilia? how does it present clinically? CXR? |
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Definition
| simple pulmonary eosinophila (loefflers) is characterized by transient pulmonary lesions, eosinophilia in the blood, alveolar septa thickened by infiltrate of eosinophils, but no fibrosis/vasculitis/necrosis, and a benign clinical course (though there may be background DAD) CXR: irregular intrapulmonary densities |
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Term
| what can cause secondary eosinophila? |
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Definition
| fungi, parasites, bacterial infections, drug allergies, asthma, and vascultis |
|
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Term
| what is chronic eosinophilic pneumonia? what is the clinical presentation? |
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Definition
| chronic eosinophilic pneumonia is characterized by focal areas of cellular consolidation in the periphery of the lung. heavy aggregates of lymphocytes and eosinophils are seen in the septal walls and the alveolar spaces. clinically, pts with this have a high fever, night sweats and dyspnea. chronic eosinophilic pneumonia will respond to steroids |
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Term
| what are 2 smoking related interstitial pulmonary diseases? |
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Definition
| desquamative interstitial pneumonia and respiratory bronchiolits associated lung disease |
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Term
| what happens in desquamative interstitial pneumonia? who does it affect? what is the prognosis? |
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Definition
| there are large accumulations of *airspace macrophages, leading to dyspnea/dry cough, clubbing of digits and PFTs: restrictive abnormality. this presents in the 4th-5th decade of life, is more common in men, and virtually all smokers. there is a good prognosis with steroid and smoking cessation. |
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Term
| what do the macrophages look like in desquamative interstitial pneumonia? |
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Definition
| the macrophages have a brown pigment in their cytoplasm, and some contain surfactant derived from necrotic type II pneumocytes. |
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|
Term
| how do lungs affected by desquamative interstitial pneumonia appear histologically? |
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Definition
| the alveolar septae are thickened by an infiltrate of lymphocytes and plasma cells and lined by plump pneumocytes (this lining looks like "squamous cells" - thus the name). there is mild interstitial fibrosis and emphysema is often present (due to smoking) |
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|
Term
| what is respiratory bronchiolitis-associated interstitial lung disease? |
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Definition
| pigmented intraluminal macrophages are found in the bronchioles, along with a gradual onset of dyspnea, cough, submucosal/peribronchiolar infiltrate of lymphocytes/histiocytes, mild peribronchiolar fibrosis. this is mor common in males, centrilobular emphysema if common and it may overlap with desquamative interstitial pneumonia |
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