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Terms in this set (382)
Inflammation of the nasal mucosa
What is the most common cause of rhinitis?
What lines the nasal mucosa?
How does rhinitis present?
Sneezing, congestion, runny nose (common cold)
Subtype of rhinitis
Allergic rhinitis (Type I Hypersensitivity)
What type of hypersensitivity reaction is rhinitis?
What is allergic rhinitis associated with (2)?
Subtype of rhinitis characterized by inflammatory infiltrate with eosinophils
Consequence of repeated rhinitis
Protrusion of edematous, inflamed mucosa
What causes nasal polyps (3 things)?
Repeated rhinitis, CF, aspirin-intolerant asthma
What do you test a child with nasal polyps for?
Triad of aspirin-intolerant asthma
2. Aspirin-induced bronchospasms
3. Nasal polyps
What percentage of asthmatic adults have aspirin-intolerant asthma?
Benign tumor of nasal mucosa composed of large blood vessels and fibrous tissue
Classic age/sex of angiofibroma
How does angiofibroma present?
Teenage male with diffuse epistaxis
Malignant tumor of nasopharyngeal epithelium
What is nasopharyngeal carcinoma associated with?
Who does nasopharyngeal carcinoma classically appear in (2 demographics)
African children and Chinese adults
Biopsy of pleomorphic keratin-positive epithelial cells in a background of lymphocytes is typical of...
Biopsy of nasopharyngeal carcinoma
Pleomorphic keratin-positive epithelial cells in a background of lymphocytes
What lymph nodes does nasopharyngeal carcinoma typically involve/present with?
Chinese adult male with large cervical lymph nodes
Typical presentation of nasopharyngeal carcinoma
What is the intermediate filament of epithelial cells?
Acute epiglottitis definition
Inflammation of the epiglottis
Name the two risk factors for laryngeal carcinoma
Tobacco and alcohol
Inflammation of the epiglottis
Acute epiglottitis (medical emergency)
What is the most common cause of acute epiglottitis?
H influenzae type B (in both immunized and non-immunized children)
How does acute epiglottitis present?
High fever, sore throat, drooling with dysphagia, muffled voice, inspiratory stridor
What is the main risk of acute epiglottitis?
What's another name for croup
What is the most common cause of Laryngotracheobronchitis (croup)
Inflammation of the upper airway
How does Laryngotracheobronchitis (croup) present?
Hoarse, barking cough and inspiratory stridor
Nodule that arises on the true vocal cord
Vocal cord nodule (singer's nodule)
Is vocal cord nodule usually bilateral or unilater?
What causes vocal cord nodule
Excessive use of vocal cords
What composes vocal cord nodule histologically?
Myxoid (degenerative) connective tissue
Treatment of vocal cord nodule
Resting of voice
How does vocal cord nodule present?
Benign papillary tumor of the vocal cord
What causes laryngeal papilloma?
HPV 6 and 11
What is the difference in laryngeal papillomas between adults and children?
How does laryngeal papilloma present?
Squamous cell carcinoma arising from the epithelial lining of the vocal cord (usually)
Does laryngeal carcinoma arise from laryngeal papilloma?
How does laryngeal carcinoma present?
Hoarseness, cough, stridor
What lines the vocal cords?
Vocal cord nodules
Vocal cord nodules histology
Myxoid (degenerating) connective tissue
Infection of the lung parenchyma
When does pneumonia occur?
When normal defenses are impaired
What are the normal defenses that when impaired can contribute to pneumonia development?
Impaired cough reflex, damage to mucociliary escalator, mucus pluggint
What is the mucociliary escalatory, and how can it become damaged?
The lungs are lined by ciliated epithelium, and the cilia help push mucus up out of the airway to be swallowed. It can become damaged in a viral pneumonia, which will then increase the risk of a superimposed bacterial pneumonia
Clinical features of pneumonia
Fever and chills, productive cough with yellow-green (pus) or rusty (blood) sputum, tachypnea with pleuritic chest pain, decreased breath sounds, dullness to percussion, elevated WBC
How do you make diagnosis of pneumonia (3 ways)
CXR, sputum gram stain and culture, blood cultures
What sensitizes the pleura of the lung causing pleuritic chest pain?
Bradykinin and PGE2
What are the main two mediators of pain?
Bradykinin and PGE2
What are the three classical patterns of pneumonia on CXR, and which ones are caused by bacteria vs. virus
Pneumonia characterized by consolidation of an entire lobe
What are the most common causes of lobar pneumonia?
Streptococcus pneumoniae (95%) and Klebsiella pneumoniae
What is the most common cause of community acquired pneumonia
Name the four phases of lobar pneumonia
2. Red hepatization
3. Gray hepatization
What causes red hepatization phase in pneumonia?
Exudate, neutrophils, and hemorrhage filling the alveolar air spaces, giving them a solid consistency
What causes the gray hepatization that follows red hepatization in pneumonia?
Degradation of red cells within the exudate
How does lobar pneumonia heal?
Regeneration of tissue via type II pneumocytes
What is the stem cell of the lung?
Type II pneumocytes
Pneumonia characterized by scattered patchy conoslidation centered around bronchioles
Pneumonia that is often multifocal and bilateral
What is the interstitium of the lung?
Connective tissue of the alveolar air sacs
Pneumonia characterized by diffuse interstitial infiltrates
Interstitial (atypical) pneumonia
Increased lung markings on CXR. What type of pneumonia are you considering?
Interstitial (atypical) pneumonia
How does Interstitial (atypical) pneumonia present?
Relatively mild upper respiratory symptoms, with minimal sputum and low fever
Pneumonia commonly seen in alcoholics and comatose patients
What is the most common cause of aspiration pneumonia, generally and then 3 organisms specifically
Generally: most often due to anaerobic bacteria in the oropharynx
Specifically: Bacteroides, Fusobacterium, peptococcus
Classic presentation of aspiration pneumonia, and why?
Right lower lobe abscess; right mainstem bronchus branches at a less acute angle than the left mainstem bronchus
Secondary pneumonia definition
Bacterial pneumonia superimposed on a viral upper respiratory tract infection
Name two bacterial causes of lobar pneumonia
What is the most common cause of CAP?
Cause of lobar pneumonia that presents with "red sputum jelly"
Name five causes of bronchopneumonia
Common cause of secondary pneumonia and pneumonia superimposed on COPD (COPD exacerbation)
Pneumonia in cystic fibrosis patients
Pneumonia transmitted from water source
Intracellular organism that is best visualized by silver stain
Name six causes of interstitial (atypical) pneumonia
Respriatory syncytial virus (RSV)
Common cause of atypical pneumonia that affecst young adults (military recruits or those in dorms); complicatiosn include autoimmune hemolytic anemia (IgM against I antigen on RBCS causes cold hemolytic anemia) and erythema multiforme
Why is Mycoplasma pneumoniae not visible on gram stain?
Lack of cell wall
Second most common cause of atypical pneumonia in young adults
Most common cause of atypical pneumonia in infants
Respriatory syncytial virus (RSV)
What does atypical pneumonia caused by influenza virus increase the risk for
Secondary bacterial pneumonia by S aureus or H influenza
Name the three ways coxiella burnetii is different from most rickettsiae
Causes pneumonia, does not require arthropod vector for transmission (because it survives as heat resistant endospores), does not produce a skin rash
Atypical pneumonia with high fever
coxiella burnetii (seen in farmers and vets)
Where are coxiella spores present?
Deposited on cattle by ticks; present in cattle placentas
What causes TB?
Inhalation of aerosolized mycobacterium tuberculosis
What are the two types of TB?
Primary and secondary
Focal, caseating necrosis in lower lobe of the lung and hilar lymph nodes that undergo fibrosis and calcification, forming a Ghon complex
Seen in primary TB; area of fibrosis/calcification indicating primary TB
Is primary TB symptomatic or asymptomatic?
Astymptomatic, but leads to positive PPD
What causes secondary TB?
Reactivation of mycobacterium tuberculosis
Causes of reactivation of mycobacterium tuberculosis
Aging; AIDS is common cause
Where does secondary TB arise, and why?
Apex of the lung where there is poor lymphatic drainage and high oxygen tension
Clinical features of secondary TB
Fevers, night sweats, cough with
, weight loss
What type of TB forms cavitary foci of caseous necrosis, and it can also lead to miliary pulmonary TB or TB Bronchopneumonia?
Tiny regions of TB all over lung
What can secondary TB lead to?
Miliary TB or tuberculous bronchopneumonia
Biopsy of secondary pneumonia
DDX of caseating granulomas
Fungal or TB
How do you confirm TB vs. fungi after seeing caseating granulomas?
Acid Fast Stain
Acid fast bacilli TB
Name common sites of systemic spread of secondary TB
Meninges - meningitis
Cervical lymph nodes - scrofula
Kidneys - sterile pyuria
Lumbar Vertebrae - Pott's dz
Where are granulomas located when secondary TB goes to the meninges?
Base of the brain
What is the most common site of systemic spread of secondary TB, and what does it cause there?
Kidney, causes sterile pyuria
Name for TB in lumbar vertebrae
Group of diseases characterized by airway obstruction in which the lung does not empty and air is trapped
Obstructive pulmonary diseases
Spirometry findings in obstructive pulmonary diseases
Decreased FVC, decreased FEV1, decreased FEV1/FVC,
Stands for forced vital capacity; amount of air you can breath out after maximum inhalation
Total lung capacity (increased in chronic obstructive pulmonary diseases)
What is normal TLC?
7 L, usually goes up to 8 in obstructive lung diseases
How is chronic bronchitis defined?
What is chronic bronchitis associated with?
Definition of chronic bronchitis
Chronic productive cough lasting at least 3 months over a minimum of 2 years
What glands hypertrophy in chronic bronchitis?
Chronic bronchitis histology
Mucinous gland hypertrophy
Reid Index; what is it and how does it change in chronic bronchitis?
Reid index: thickness of mucinous glands relative to the thickness of the entire wall
Increases from under 40% to 50% in chronic bronchitis
Normal Reid Index
Less than 40%
Name the layers of the bronchus
Lumen- lined by pseudostratified columnar ciliated epithelium
Lamina propria- contains the venules that warm air before it goes to the bottom of the lung for exchange
Submucosa- contains serous and mucinous glands
What are the two types of glands in the submucosa of the bronchus of the lungs, and what do they each do?
Serous- produces watery fluid that humidifies air
Mucinous- produces mucus to line epithelium and prevent bad things from entering the lungs
Clinical features of chronic bronchitis
1. Productive cough
2. Cyanosis (blue bloater)
3. Increased infection and cor pulmonale risk
Why do those with chronic bronchitis have cyanosis?
Trapped air increases PCO2, which decreases PAO2 and subsequently PaO2
Right heart failure secondary to increased lung pressures
The lung clamps down everywhere looking for fresh air
How does chronic bronchitis cause cor pulmonale?
When the entire lung is infected, arterioles everywhere try to clamp down and send blood elsewhere for oxygenation; this leads to increased pressures, causing the right heart to hypertrophy and then eventually fail
Destruction of alveolar air sacs
Name the four chronic obstructive pulmonary diseases
1. Chronic bronchitis
How does emphysema result in obstructive disease?
Loss of elastic recoil in alveolar air sacs and subsequent collapse of airways during exhalation results in obstruction and air trapping
one big shopping bag
What is the difference between bronchus and bronchioles?
Bronchioles do not have cartilage to help them stay open, but bronchus do
How do bronchioles stay open?
Air sacs on bronchioles have elastic recoil, which pull open walls
What is the imbalance and cause of emphysema?
Imbalance of proteases and antiproteases
What is the main defense mechanism at the very bottom of the lung?
Alveolar macrophage (eat things that escape mucus defense of upper lung and get to bottom of lung)
What is the most common cause of emphysema?
Smoking, lots of proteases
Name two causes of emphysema
Alpha-1 Anti Trypsin Deficiency
What is a rare cause of emphysema?
Alpha-1 Anti Trypsin Deficiency
Where is alpha-1 antitrypsin deficiency emphysema most severe in the lung
Panacinar emphysema that is most severe in lower lobes
What are the two major types of emphyseam?
What is the functional unit of the lung?
Acinus (terminal bronchiole opens into alveolar air sac)
What type of emphysema do smokers get, and where is it most severe?
Centriacinar emphysema more severe in upper lobes
A1AT accumulation in hepatocytes on histology
Purple or pink colored globules are alpha-1 anti trypsin that are PAS positive
Name two late complications of emphysema
2. Cor pulmonale
PaO2 < 60
What causes normal inflammation in the lungs?
Alveolar macrophages eating "bad" particles that have made it to the bottom of the lung
What does inflammation of the lung as caused by alveolar macrophages lead to?
Release of proteases by neutrophils and macrophages
What neutralizes proteases released by normal inflammation in the lung?
Anti-proteases, typically alpha-1 antitrypsin
What causes destruction of the air sacs in emphysema?
Either too many proteases released or deficiency of anti-proteases
What often can accompany emphysema due to alpha-1 antitrypsin?
What causes liver cirrhosis in emphysema due to alpha-1 antitrypsin?
Mutant A1AT misfolded protein accumulates in the ER of hepatocytes, causing liver damage
Diagnosis of biopsy of pink, PAS positive globules in hepatocytes
Liver cirrhosis due to accumulation of A1AT accumulation in ER of hepatocytes
What is severity of emphysema due to alpha-1 antitrypsin based on?
Degree of A1AT deficiency
What is the normal allele associated with A1AT?
PiM (two copies PIMM)
What is the most common clinically relevant mutation leading to A1AT deficiency, and what does it cause?
PiZ, causes significantly low levels of circulating A1AT
accumulates in endoplasmic reticulum
What is the clinical picture of PiMZ heterozygotes in relation to A1AT deficiency emphysema?
Asymptomatic with decreased circulating levels of A1AT and increased risk for emphysema with smoking
What are PiZZ homozygotes at risk for?
Panacinar emphysema and cirrhosis
Clinical features of emphysema
1. Dyspnea, cough (with minimal sputum)
2. Prolonged expiration with pursed lips
3. Weight loss
4. Barrel chest
5. Hypoxemia and cor pulmonale as complications
Cough in chronic bronchitis vs. cough in emphysema
Chronic bronchitis- abundant sputum
Emphysema- little sputum
What is Functional Residual Capacity (FRC)?
Point at which the tendency of the chest to push outwards meets the tendency of the lungs to collapse
How is FRC altered in emphysema?
Increased in emphysema, resulting in "barrel-chest"
How is FRC altered in fibrosis?
What causes late complication of hypoxemia in emphysema?
Destruction of capillaries in alveolar air sac
What is the most common stimulator for asthma?
Allergic stimuli (atopic asthma)
Asthma due to allergic stimulie
Reversible airway bronchoconstriction, most often due to allergic stimuli
What type of sensitivity reaction is atopic asthma?
Type I Hypersensitivity
When does asthma commonly present?
Name three things asthma is associated with
1. Allergic rhinitis
3. Family history of atopy (hyperallergic)
Pathogenesis of Asthma
1. Allergens induce Th2 phenotype in CD4+ T cells in genetically susceptible individuals
2. Th2 cells secrete IL4, IL5, and IL10
3. Reexposure to allergen leads to IgE mediated activation of mast cells
What are the interleukins that Th2 cells secrete, and what does each do?
1. IL4 (mediates class switch to IgE)
2. IL5 (attracts eosinophils)
3. IL10 (stimulates Th2 cells and inhibits Th1 cells)
How does the allergen that incites asthma affect mast cells- what does it do to surface IgE?
Allergen crosslinks surface IgE on mast cells
What is the immediate response of mast cells to IgE linkage by allergen?
Release of preformed histamine granules
Generation of leukotrienes C4, D4, E4
Two actions of histamine
Induces vasodilation at arterioles and leaking of fluid at post-capillary venules
What does histamine and leukotrines C4, D4, and E4 cause when they are released by mast cells in asthmatic?
Bronchoconstriction, inflammation, edema (early phase reaction)
What causes the late phase reaction in asthma?
Inflammation, especially major basic protein derived from eosinophils, damages cells and perpetuates bronchoconstriction
Clinical features of asthma
1. Episodic and related to allergen exposure
2. Dyspnea and wheezing
3. Productive cough with spiral shaped mucus plugs (Curschmann spirals) and eosinophil derived crystals (Charcot-Leyden crystals major basic protein)
4. Severe, unrelenting attack can cause status asthmaticus and death
How can asthma result in death?
Severe, unrelenting attack can cause status asthmaticus and death
Eosinophils major basic protein derived crystals in asthma
Spiral shaped mucus plugs seen in asthmatics
Name four nonallergic asthmatic causes (non-atopic asthma)
2. viral infection
3. Aspirin (aspirin intolerant asthma)
4. Occupational exposures
Triad of aspirin intolerant asthma
2. Bronchospasm with aspirin
3. Nasal polyps
Permanent dilation of bronchioles and bronchi causing a loss of airway tone and resultant air trapping (large airway presents airway from being accelerated out the other end)
What is the cause of bronchiectasis?
Necrotizing inflammation with damage to airway walls
Name causes of necrotizing inflammation that lead to damage in airway walls and ultimately bronchiectasis
Allergic bronchopulmonary aspergillosis
What is the defect in Kartagener syndrome?
Inherited defect in dynein arm of cilia, preventing ciliary movement
What is Kartagener syndrome associated with? 3 things
Sinusitis, infertility, situs inversus
Populations prone to get Allergic bronchopulmonary aspergillosis
What is Allergic bronchopulmonary aspergillosis
Hypersensitivity reaction to aspergillus leading to chronic inflammatory damage
Clinical features of bronchiectasis
Cough, dyspnea, foul-smelling sputum
Why is the sputum in bronchiectasis foul smelling?
It has been rotting while sitting in the lung, unable to escape the airways
Complications of bronchiectasis
Hypoxemia with cor pulmonale and secondary AA amyloidosis
What is amyloidosis?
Deposition of a misfolded protein that can be localized or systemic; if systemic, can be primary (AL deposited due to plasma cell issue) or secondary (AA deposited due to chronic inflammation and overproduction of SAA which becomes AA)
Problem in restrictive lung diseases versus problem in obstructive lung diseases
Restrictive: can't fill
Obstructive: can't empty
What is the problem in restrictive lung diseases?
Inability to fill due to interstitial diseases of the lung or other chest wall abnormalities
TLC, FEV1, FVC, and FEV1:FVC in restrictive diseases
Decreased TLC, decreased FEV1, decreased FVC, and increased FEV1:FVC ratio
What is the most common cause of restrictive lung disease and a secondary cause?
Most common: interstitial diseases of the lung
Another cause: chest wall abnormalities (obesity)
How much of the lung in the air is normally blown out in the first second?
Idiopathic pulmonary fibrosis defintion
Fibrosis of lung interstitium
Idiopathic pulmonary fibrosis
Way too thick
Etiology of idiopathic pulmonary fibrosis
Unknown, but likely related to cyclical lung injury and TGF-Beta from injured pneumocytes, which induces fibrosis
What is released from injured pneumocytes in idiopathic pulmonary fibrosis that induce fibrosis
Etiology of non-idiopathic pulmonary fibrosis
Drugs (bleomycin and amiodarone) and radiation therapy
Name two drugs that can cause idiopathic pulmonary fibrosis
Bleomycin and amiodarone
Treatment for idiopathic pulmonary fibrosis
Lung transplantation (no way to remove the fibrosis)
Clinical features of idiopathic pulmonary fibrosis
1. Progressive dyspnea and cough
2. Fibrosis on lung CT (honeycomb lung)
idiopathic pulmonary fibrosis findings on CT
Fibrosis, initially seen in subpleural patches but eventually results in diffuse fibrosis with end-stage "honeycombing" of the lung
What disease end-stage has honeycombing of lung?
idiopathic pulmonary fibrosis
Interstitial fibrosis due to occupational exposure, which results in chronic exposure to small, fibrogenic particles
What induces fibrosis in pneumoconioses?
Alveolar macrophages, which engulf the foreign particles and induce fibrosis
Name four entities that can cause pneumoconioses
1. Carbon dust
Why are the particles that cause pneumoconioses small?
They must be small enough to escape the defenses of the lung and reach the bottom to activate macrophages, which induce the fibrosis that results in problems
What is black lung associated with?
Rheumatoid arthritis, called Caplan Syndrome
Coal worker's pneumoconioses that is caused by carbon dust that leads to diffuse fibrosis (and shrunken lung)
What does mild exposure to carbon (pollution) result in, and where?
Anthracosis (collection of carbon-laden macrophages) in lungs and hilar lymph nodes
Collections of carbon-laden macropahges due to mild exposure to carbon (i.e. pollution)
Who is silicosis seen in?
Sandblasters and silica miners
Fibrotic nodules in upper lobes of the lung
Upper lobes is a hint- this can increase TB risk, and TB is in the upper lobes also
What does silicosis increase the risk for, and why?
TB, because it impairs phagolysosome formation by macrophages when it enters the macrophages
Who is at risk for berylliosis?
Miners and workers in aerospace industry
Noncaseating granulomas in the lung, hilar lymph nodes, and systemic organs
What do you not want to confuse berylliosis with?
What does Berylliosis increase the risk for?
Who is at risk for asbestosis
Construction workers, plumbers, shipyard workers
What can asbestosis lead to?
1. Fibrosis of lung and/or pleura
2. Cancer of lung and/or pleura
Lesions in asbestosis
Long, golden brown fibers with associated iron; called asbestos bodies or ferruginous bodies
What confirms exposure to asbestos?
asbestos bodies/ferruginous bodies
Asbestos bodies/ferruginous bodies
Systemic disease characterized by noncaseating granulomas in multiple organs
Who is sarcoidosis most commonly seen in?
African American women
What is etiology of sarcoidosis?
Unknown; likely due to CD4+ helper T cell response to unknown antigen
Where are granulomas in sarcoidosis most commonly located?
Hilar lymph nodes and lung, leading to restrictive lung disease
What is the characteristic histologic feature seen in sarcoidosis?
Asteroid bodies seen within giant cells of the granulomas
Name tissue commonly involved in sarcoidosis
1. Lungs/hilar lymph nodes
2. Uvea (uveitis)
3. Skin (cutaneous nodules or erythema nodosa)
4. Salivary and lacrimal glands (
mimics Sjogren Syndrome)
What is the triad of symptoms associated with Sjogren Syndrome?
1. Can't chew a cracker
2. Dust in eye
3. Increased risk for dental cavities
What is the most common presenting symptom of sarcoidosis?
Clinical features of sarcoidosis
1. Dyspnea or cough (cough most common presentation)
2. Elevated serum ACE
What is ACE level in sarcoidosis
Why is there hypercalcemia in sarcoidosis?
1-alpha hydroxylase activity of epithelioid histiocytes composing noncaseating granulomas converts Vitamin D to its active form
Treatment for sarcoidosis
Steroids; will often resolve without treatment
What is seen histologically in hypersensitivity pneumonitis?
Granulomas with eosinophils
Two restrictive lung disease characterized by non-caseating granulomas
1. Berylliosis (pneumoconiosis)
hypersensitivity pneumonitis definition
Granulomatous reaction to inhaled organic agents (i.e. pigeon breeder's lung)
Granulomas with eosinophils!
What is pigeon breeder's lung?
How does hypersensitivity pneumonitis present?
Fever, cough, dyspnea just hours after exposure
How do you treat hypersensitivity pneumonitis
Resolves with removal of exposure
What does chronic exposure of organic agents that cause hypersensitivity pneumonitis result in?
Name the four restrictive diseases
-Idiopathic pulmonary fibrosis
Pulmonary hypertension definition
High pressure in the pulmonary circuit (over 25 mmHg)
What is normal pressure in pulmonary circuit?
Plexiform lesions pulmonary hypertension
Tufts of capillaries
Name the four things that characterize pulmonary hypertension
1. Atherosclerosis of pulmonary trunk
2. Smooth muscle hypertrophy of pulmonary arteries
3. Intimal fibrosis
4. Plexiform lesions with severe, long standing disease (pic)
What lesions are seen in severe, long standing pulmonary hypertension?
What can pulmonary hypertension eventually lead to?
Right ventricular hypertrophy with eventual cor pulmonale
How does pulmonary hypertension present?
Exertional dyspnea or right sided heart failure
What are the two types of pulmonary hypertension?
Primary or secondary
Who is classically affected with primary pulmonary hypertension?
Young adult females
What mutation is often associated with primary pulmonary hypertension
BMPR2 inactivating mutation, leading to proliferation of vascular smooth muscle?
What does BMPR2 inactivating mutation associated with?
Proliferation of vascular smooth muscle, leading to primary pulmonary hypertension
Name three causes of secondary pulmonary hypertension
1. Hypoxemia (as in COPD or interstitial lung disease)
2. Increased volume in pulmonary circuit (i.e. congenital heart disease)
3. Chronic recurrent PE
What are the four symptoms/outcomes of PE?
2. Pulmonary infarction
3. Sudden death (saddle embolus)
4. Chronic PE can become reorganized and lead to thickening of vascular wall and ultimately pulmonary hypertension
What does increased volume in the pulmonary circuit (as in congenital heart disease) cause in the smooth muscle?
Hypertrophy, which can lead to pulmonary hypertension
What is damaged in acute respiratory distress syndrome?
Alveolar-capillary interface (diffuse alveolar damage within the air sac)
Pathogenesis of ARDS
Damage to alveolar-capillary interface leads to leakage of protein-rich fluid, which causes edema and is reorganized with necrotic epithelial cells to form hyaline membranes in alveoli
Characteristic features of ARDS on pathology
Chest x-ray finding in ARDS
Clinical features of ARDS
Hypoxemia and cyanosis with respiratory distress due to thickened diffusion barrier and collapse of air sacs due to increased surface tension
Name some causes of ARDS (lots!)
Sepsis, infection, shock, trauma, aspiration, pancreatitis, DIC, hypersensitivity reactions, drugs
How are type I and II pneumocytes damaged in ARDS?
Activation of neutrophils induce protease and free-radical mediated damage of I AND II pneumocytes
What pneumocytes are damaged in ARDS?
I and II
Treatment of ARDS
1. Treat underlying cause
2. Ventilation with PEEP (positive end-expiratory pressure)
What can complicate recovery of ARDS?
Interstitial fibrosis- loss of type II pneumocytes prevents regeneration (stem cells)
Why do you include ventilation with positive end expiratory pressure in treatment of ARDS?
Patients have collapse of air sacs due to increased surface tension, so leaving some pressure in the lungs at the end of expiration will help keep the sacs open to be filled on inhalation
Name the two respiratory distress syndromes
1. Acute respiratory distress syndrome
2. Neonatal respiratory distress syndrome
Neonatal respiratory distress syndrome definition
Respiratory distress in neonates due to inadequate surfactant levels
What is the major component of surfactant?
What is the role of surfactant in the lungs?
Decreases surface tension in the lung to prevent the collapse of alveolar air sacs after respiration
What does lack of surfactant lead to?
Collapse of air sacs (making it hard to fill them back up) and formation of hyaline membrane disease
Name three things neonatal respiratory distress syndrome is associated with
3. Maternal diabetes
When does surfactant production begin, and when is it adequate?
Begins: 28 weeks
Adequate: 34 weeks
How do you screen for lung maturity in neonates?
L:S ratio (lecithin to sphingomyelin ratio)
Lecithin should increase with gestational age; sphingomyelin should remain constant
What is another name for lecithin that is the major component of surfactant?
What is the L:S ratio that indicates adequate surfactant production?
Why is C-section associated with increased risk for neonatal respiratory distress syndrome?
Stress induced steroids are not released, and steroids increase the synthesis of surfactant
How does maternal diabetes increase risk for neonatal respiratory distress syndrome
Insulin is increased in the fetus due to high blood sugar in the mom; insulin inhibits surfactant production
How does insulin affect surfactant production?
Clinical features of neonatal respiratory distress syndrome
1. Increased respiratory effort after birth, tachypnea with use of accessory muscles, grunting
2. Hypoxemia with cyanosis
3. Diffuse granularity of lung on x-ray (ground glass appearance)
How does x-ray of infant with neonatal respiratory distress syndrome appear?
Granularity of lung with ground glass appearance
Name complications of neonatal respiratory distress syndrome
1. Hypoxemia increases risk of persistent PDA and necrotizing enterocolitis
2. Supplemental oxygen increases risk for free radical injury (blindness, bronchopulmonary dysplasia)
Neonatal respiratory distress syndrome chest x-ray
When does patent ductus arteriosus close?
When there is good oxygenation of the blood
What are the risks of giving supplemental oxygen in neonatal respiratory distress syndrome due to free radical formation
1. Retinal injury leading to blindness
2. Lung damage leading to bronchopulmonary dysplasia
What is the average age of lung cancer presentation?
What is the most common cancer mortality in the US?
What is the most common incidence of cancer (top 3) in the US?
Name three risk factors for lung cancer
Cigarette smoke, radon, asbestos
What percentage of lung cancer occurs in smokers?
How many carcinogens are there in cigarette smoke?
Name the two most mutagenic carcinogens in cigarette smoke
Polycyclic aromatic hydrocarbons and arsenic
What is cancer risk from smoking directly related to?
Duration and amount of smoking (pack years)
How is radon, which is a risk of lung cancer apart from cigarette smoke, formed
Radioactive decay of uranium, which is present in the soil
Where and how does radon often accumulate?
Basements as colorless, odorless gas
What is the second most frequent cause of lung carcinoma in US?
What is responsible for most of the public's exposure to ionizing radiation?
What are uranium miners at increased risk for, and why?
Lung cancer, because uranium degrades into radon, which increaseas lung cancer risk
What are presenting symptoms of lung cancer
Non-specific (cough, weight loss, hemoptysis, postobstructive pneumonia)
What does imaging of lung cancer often reveal?
Coin lesion, or solitary nodule
What is the next step upon finding a coin lesion on x-ray
Compare to prior x-ray to see if it is new (likely lung cancer) or not
Name examples of lesions that can produce coin lesions in patients and mimic lung cancer on x-ray
Granuloma (due to TB or fungus like Histoplasma in the midwest)
What is a bronchial hamartoma?
Benign tumor composed of lung tissue and cartilage that is often calcified on imaging (disorganized tissues)
Benign tumor composed of lung tissue and cartilage that is often calcified on imaging
What is a hamartoma?
Disorganized tissue that is composed of correct tissue for the location
What are the two categories of lung carcinoma?
Small cell and non-small cell
What percentage of lung cancer is small cell, and what percentage is non-small cell
Small cell: 15%
Non small cell: 85%
How do you treat small cell lung cancer versus non small cell lung cancer?
Small cell: chemo, not usually surgical resection
Non-small-cell: surgical resection, not chemo
Name the four subtypes of non-small cell lung carcinoma
2. Squamous cell
3. Large cell
4. Carcinoid tumor
Association and location of small cell carcinoma
Associated with male smokers
Poorly differentiated small cell lung cancer that arises from neuroendocrine cells
Small cell carcinoma
What are the paraneoplastic syndromes small cell carcinoma can cause?
ADH, ACTH, or Eaton-Lambert syndrome
What is eaton-lambert syndrome?
Paraneoplastic syndrome often present with small cell carcinoma in which there are Abs against presynaptic Ca channels that can result in muscle weakness
Association and location of squamous cell carcinoma
Association: male smokers
Lung cancer defined histologically by keratin pearls or intercellular bridges
Squamous cell carcinoma
What can squamous cell carcinoma produce, and what does it cause?
PTHrP, causing hypercalcemia
Association and location of adenocarcinoma
Association: non-smokers (most common lung cancer in non-smokers) and female smokers
Location: peripheral lung
Lung cancer defined histologically by glands or mucin
Lung cancer defined by poorly differentiated large cells, but not other features of non-small cell carcinoma
Large cell carcinoma
Association and location of large cell carcinoma
Location: central or peripheral
Prognosis of large cell carcinoma?
Association and location of bronchioloalveolar carcinoma
Association: not related to smoking
Lung cancer characterized by columnar cells tha tgrow along preexisting bronchioles and alveoli
Where does bronchioloalveolar carcinoma arise from?
How does bronchioloalveolar carcinoma appear on imaging?
Prognosis of bronchioloalveolar carcinoma?
Lung cancer defined by well differentiated neuroendocrine cells that are chromogranin positive
Association and location of carcinoid tumor
Association: not to smoking
Location: central or peripheral
How does carcinoid tumor appear if it is centrally located?
Forms polyp-like mass in bronchus
Is carcinoid tumor high or low grade malignancy?
What paraneoplastic syndrome can carcinoid tumor sometimes cause?
What are the most common mets to the lung?
Breast and colon
How do mets to the lung appear on imaging?
Cannon ball nodules
Are primary tumors or mets in the lung more common?
Name the two neuroendocrine lung cancers and what differentiates them
Small cell: poorly differentiated
Carcinoid: well differentiated
Both chromogranin positive
TNM stands for...
Tumor size and local extension
Mets (to adrenal gland is UNIQUE)
What cancer most commonly involves pleural involvement?
Adenocarcinoma (peripheral location)
Superior vena cava syndrome
Seen in lung cancer that obstructs the SVC and causes distended head and neck veins with edema, blue discoloration of arms and face
What nerves can be involved in lung cancer?
Recurrent laryngeal (hoarseness)
Phrenic (diaphragmatic paralysis)
Small cell carcinoma histology picture
mitotic figure at bottom left
Squamous cell carcinoma keratin pearls
Can also see intercellular bridges
What normally connects squamous cells?
Bronchioloalveolar carcinoma histology
Lung carcinoid tumor
Horner syndrome in lung cancer- what causes it, and what are symptoms
Compression of sympathetic chain, leading to ptosis, miosis (pinpoint pupil), anhidrosis (no sweating)
What nodes does lung cancer spread to first?
Hilar and mediastinal
What is a unique site of distant mets for lung cancer?
5 year survival of lung cancer, and why so low?
15%; presents late due to no effective screenings
What are the two layers of pleura?
Visceral (on lungs) and parietal (on chest wall)
What cells line the pleura, and what do they make?
Mesothelial cells line the pleura, and they make fluid to lubricate the pleural space
What causes a spontaneous pneumothorax?
Rupture of an emphysematous bleb
In who is a spontaneous pneumothorax seen?
How is trachea shifted in spontaneous pneumothorax?
Toward side of collapse
Name the two types of pneumothorax
Tension pneumothorax caused by...
Penetrating chest wall injury
How does trachea shift in tension pneumothorax?
Away from side of injury
How do you treat tension pneumothorax?
Medical emergency treated with chest tube
Malignant neoplasm of mesothelial cells that is associated with occupational asbestos exposure
How does mesothelioma present?
Recurrent pleural effusions, dyspnea, chest pain
Tumor encases lung
Why does mesothelioma present with recurrent pleural effusions?
Mesothelial cells normally make fluid!
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