9.5 - 9.9: Restrictive Lung Diseases and rest of Respiratory Flashcards
What happens to the TLC with restrictive lung diseases? FVC? FEV1?
All decrease, especially FVC
What happens to the FEV1:FVC ratio with restrictive diseases? Why?
Increased, since FVC falls more than FEV1
Why is it that the FEV1 does not fall very much with restrictive diseases?
Increased elastic recoil of the lungs causes an increase in the flow of air out of the lungs
Why do interstitial diseases lead to restrictive lung pathologies?
Fibrosis of the alveoli impede the opening of the alveolar sacs, as well as the gas exchange
What is idiopathic pulmonary fibrosis?
Fibrosis of the lung interstitium
What is the (known) etiology of idiopathic pulmonary fibrosis?
TGF-beta increased, causing cyclical lung injury and repair
What is the role of TGF-beta normally?
Encourages repair and growth
What are the two drugs that commonly cause lung injury?
- Bleomycin
- Amiodarone
What are the s/sx of idiopathic pulmonary fibrosis?
- Progressive dyspnea and cough
- Fibrosis on lung CT
What is the treatment for idiopathic pulmonary fibrosis?
Lung transplant–NOT steroids
Where in the lung does idiopathic pulmonary fibrosis occur?
Subpleural
What is pneumoconioses?
Interstitial fibrosis due to occupational exposure of small particles
What is the etiology of pneumoconiosis?
Small particles slip past mucosal defense and hit the alveoli, where macrophages freak out and induce fibrosis in the lung.
What is coal worker’s pneumoconioses? What happens to the lungs with this?
Carbon dust gets into the alveoli, causing massive fibrotic changes and shrunken lung
What is silicosis? Where in the lung does it occur, and how does it predispose to infx?
Silica sand pneumoconiosis usually occurring in the upper lobe of the lung, and impairs phagolysosome production in macrophages
What is berylliosis? What lung changes does this cause?
- Be pneumoconiosis
- Noncaseating granulomas in the hilar lymph nodes
What is mesothelioma?
Asbestos pneumoconiosis
What is anthracosis?
Benign build up of carbon in macrophages d/t air pollution
What is the only pneumoconiosis that increases the risk for TB? Why?
- Silicosis
- D/t impairment of the phagolysosome formation
Berylliosis is very similar to what other pathological condition? Why?
- Sarcoidosis
- Noncaseating granuloma formation in the lungs and systemically
Which of the pneumoconioses poses an increased risk for the development of cancer?
- Berylliosis
- Asbestos
Who is usually exposed to silica sand?
Sand blasters in construction
Who is usually exposed to beryllium?
Aerospace workers
Who is classically exposed to asbestos? What does it cause?
- Shipyard workers or construction workers
- Fibrosis of the lung/pleura
- Cancer of the lung/pleura
Which is more common with asbestos exposure: mesothelioma, or lung cancer
Lung cancer
What are asbestos bodies?
Long rod-like Fe deposits, causing ferruginous bodies
What is sarcoidosis?
Systemic disease characterized by noncaseating granulomas in multiple organs
In whom is sarcoidosis usually seen?
African american females
What is the etiology of sarcoidosis?
Unknown, but likely due to CD4+ helper T cell response to an unknown antigen
What is the defining cell of granulomas?
Epithelioid histiocyte
What does non-caseating mean in the context of granulomas?
All of the cells in the granuloma are alive
What is the hallmark histological finding of sarcoidosis?
Asteroid body
Which parts of the lung are most commonly affected by sarcoidosis?
hilar lymph nodes
What type of lung disease does sarcoidosis eventually lead to?
Restrictive lung disease
Sarcoidosis of the eye causes what?
Uveitis
Sarcoidosis of the skin causes what?
Cutaneous nodules
Sarcoidosis of the salivary glands causes what?
Sjogren’s - like syndrome
What are the clinical features of sarcoidosis? (ssx, labs x2)
- SOB/cough
- Elevated ACE
- Hypercalcemia
What is the treatment for sarcoidosis? Prognosis?
Steroids, but usually self limiting
Why is there hypercalcemia with sarcoidosis?
granulomas have alpha-1-hydroxylase activity, and can activate Vit D
What is hypersensitivity pneumonitis?
Granulomatous reaction to inhaled organic antigens
What are the s/sx of hypersensitivity pneumonitis?
Fever, cough, SOB
Chronic exposure to the antigen in hypersensitivity pneumonitis leads to what?
Interstitial fibrosis
—What are the cells that are classically found in the granulomas of hypersensitivity pneumonitis—
—Eosinophils—
What is the range of normal pulmonary BP? What defines pHTN?
- Normal = 10 mmHg
- pHTN = more than 25 mmHg
What are the three major vessel changes that occur with pHTN?
- Atherosclerosis of pulmonary trunk
- Smooth muscle hypertrophy of pulmonary arteries
- Intimal fibrosis
What are the hallmark lesions that are associated with chronic pHTN? What are these composed of?
- Plexiform lesions
- Tufts of capillaries nestled together
What is the classic symptom of pHTN?
DOE
What is the heart sequelae of untreated pHTN?
RVH
Which gender is more classically affected with pHTN? What age (generally)?
Young Women
What is the genetic cause of the familial form of pHTN? What does this cause?
BMPR2, inactivating mutation, leading to proliferation of vascular smooth muscle
How does chronic hypoxemia (e.g. COPD, interstitial lung disease) lead to RVH and pHTN?
Increased capillary resistance
How do recurrent PEs cause pHTN?
Increasing pressure via blockage, or remodeling of the pulmonary artery
What is the histological change that occurs with ARDS? What happens to gas exchange?
- Hyaline membrane formation d/t leaky capillaries and protein deposition
- Leads to reduced gas exchange
Why does diffuse collapse of the lung occur with ARDS?
Hyaline membranes stick to one another, causing alveoli to collapse
What are the CXR findings of a patient with ARDS?
“White out” of the lung
What are the s/sx of ARDS?
Hypoxemia and cyanosis with respiratory distress
What are the cells that are damaged in ARDS?
Type I and II pneumocytes
What are the immune cells that induce damage in ARDS?
Activated PMNs
Why is PEEP necessary with ARDS?
Hyaline membranes will stick to one another and increase surface tension, so keeping in pressure will prevent from sticking
What causes the interstitial fibrosis with ARDS?
Damage of the type II Pneumocytes (stem cells) means lung lining cannot heal well
What is the cause of NRDS?
Inadequate surfactant levels
What are the cells in the lungs that produce surfactant? What else do these cells do?
- Type II pneumocytes
- Also the stem cells of the lung
What is the use (benefit) of surfactant?
Reduce surface tension so less energy is needed to open alveoli
What are the s/sx of NRDS?
Respiratory distress after birth, leading to cyanosis
What are the classic CXR findings of NRDS?
Granularity of the lung
What are the three major causes of NRDS?
- Prematurity
- C-section delivery
- Maternal DM
When in gestation does surfactant production begin? When is it adequate?
28 weeks
34 weeks is sufficient
What are the two components of surfactant, and how is the ratio of these two used to determine if a child is ready to be born?
Lecithin and Sphingomyelin
L:S ratio greater than 2
What is the major lipid found in surfactant?
Phosphatidylcholine (= Lecithin)
Why can C-section delivery cause NRDS?
No release of endogenous corticosteroids to increase surfactant production (normally happens with stress from vaginal delivery)
How can maternal DM cause NRDS?
Maternal BG levels will increase insulin levels in the fetus, which inhibit surfactant production
What are the two major complications of NRDS? Why?
- PDA (hypoxemia keeps it open)
- Necrotizing enterocolitis (hypoxia of the gut)
—-What is the harm of administering oxygen to NRDS pts? What are the two major pathologies that can occur if this happens?—–
- Free radical formation
- Blindness (retinopathy of prematurity) and bronchopulmonary dysplasia
What is the average age on presentation for lung CA?
60 years
What are the three key environmental risk factors for the development of lung CA?
- Cigarette smoke
- Radon
- asbestos
What is the major carcinogenic component found in cigarettes?
Polycyclic aromatic hydrocarbons
What is Radon formed from?
Decay product of Uranium
What is the classic CXR finding of lung cancer?
Solitary “coin” lesion
What is the first step when a nodule is found on a CXR?
Compare to priors
Under what age are coin lesion more likely to be benign?
35 ish
What are the causes of benign coin lesions? (2)
- Granulomas
- Bronchial hamartoma
Granulomas in the lung, particularly in the midwest, are often caused by what infectious agent?
Histoplasmosis
What is a hamartoma?
Dysplastic tissue that belongs in that area, but is disorganized
What are the two components of bronchial hamartomas?
Lung tissue and cartilage
What are the two major classes of lung cancer?
Small cell and non-small cell
True or false: small lung cell CA is almost never treated with surgery
True
Cancerous mass in the lung that produces mucus and is glandular is what type of cancer?
Adenocarcinoma
What are the key histological findings of squamous cell carcinoma?
Keratin pearls and intercellular bridges
What are the top three cancers in the US by incidence?
- Breast/prostate
- Lung
- Colorectal
What are the top three cancers in the US by mortality?
- Lung
- Prostate/breast
- Colorectal
What are the histological characteristics of small cell lung carcinoma?
Poorly differentiated small cells that arise from neuroendocrine cells
What are the histological characteristics of adenocarcinoma?
Glands or mucin production
What are the histological characteristics of large cell carcinoma?
Poorly differentiated large cells (without other characteristic findings)
What are the histological characteristics of bronchioloalveolar carcinoma? What cells do these arise from? Prognosis?
- Columnar cells that grow along preexisting bronchioles and alveoli
- Clara cells
- Good prognosis
What are the histological characteristics of carcinoid tumors (cell type, stain)?
Well differentiated neuroendocrine cells that are chromogranin positive
What are the two most common cancers that metastasize to the lungs?
Breast
Colon
Who usually gets small cell carcinoma?
Male smokers
What is the most common form of cancer in male smokers?
Squamous cell carcinoma
What is the most common form of lung cancer in female smokers?
Adenocarcinoma
True or false: Bronchioloalveolar carcinoma is not related to smoking
True
True or false: carcinoid tumors are related to smoking
False
Central or peripherally located: Small cell carcinoma?
Central
Central or peripherally located: squamous cell carcinoma?
Centrally
Central or peripherally located: adenocarcinoma
Peripherally
Central or peripherally located: large cell carcinoma
Central or peripheral
Central or peripherally located: bronchioloalveolar carcinoma
peripherally
Central or peripherally located: carcinoid tumors?
Either
True or false: mets to the lung are more common than primary tumors
True
True or false: carcinoid tumors are a low grade malignancy, but can cause carcinoid syndrome
True
What are the typical CXR findings of bronchioloalveolar carcinoma? Prognosis?
Pneumonia-like consolidation
Excellent prognosis
What endocrine signal may squamous cell carcinoma produce?
PTHrP
What are the endocrine signals that small cell carcinomas usually produce?
ACTH or ADH
What are the cells that give rise to small cell carcinomas?
Neuroendocrine cells (cells of Kulchitsky)
What is Eaton-Lambert syndrome, and what lung cancer can cause this?
Antibodies against presynaptic Ca channels in the neuromuscular junction
What is the mnemonic for remembering which lung cancers are related to smoking, and are centrally located?
If they start with the letter “S”, then they are related to “Smoking” and are “Sentrally” located
What are the intercellular bridges seen in squamous cell carcinoma?
Desmosome connections
What is the most common type of lung cancer in non-smokers? Females?
Adenocarcinoma
Lung cancer that is chromogranin positive = ?
Carcinoid tumor
Lung cancer that shows as a polyp-like mass in the bronchus = ?
Carcinoid tumor
What is the TMN staging system of cancer?
T = size and local extension N = nodes M = mets
What organs usually receive mets from the lung?
Adrenal glands
What lung cancer classically involves the pleura?
Adenocarcinoma
How can the diaphragm or voice be affected with lung cancer?
Compression of the laryngeal or phrenic nerve
—-What is a pancoast tumor?—-
—Lung cancer that compresses the sympathetic chain in the thorax, leading to Horner’s syndrome—-
What type of cells line the pleura?
Mesothelial cells
What is the most common cause of pneumothorax? In whom is this seen?
Rupture of an emphysematous bleb
Tall Young males
What way does the trachea shift with a pneumothorax? Tension pneumothorax?
Toward in normal, away if tension
What is the cause of tension pneumothoraces?
Penetrating chest wall injuries cause a hole whereby air can come in, but cannot leak out.
What is the major complication that can occur with a tension pneumothorax?
Compression of the heart
What are the usual presenting s/sx of mesothelioma?
Recurrent pleural effusions, dyspnea, and chest pain
How does mesothelioma usually appear grossly? On imaging?
- Completely surrounding the lung
- Plaques that surround the lung
What type of cancer does chromogranin stain?
neuroendocrine tumors
What is SVC syndrome?
Compression of the SVC by a pancoast tumor (classically), causing blue discoloration of the face, and edema
