Respiratory System Diseases Flashcards
What is another name for infectious rhinitis?
The common cold
What type of pathogen is the most common cause of infectious rhinitis?
Rhinoviruses
Describe the clinical presentation of infectious rhinitis
- Nasal congestion with watery discharge
- Sneezing
- Scratchy, dry, sore throat
What are some potential complications of infection rhinitis? (3)
- Bacterial infection due to swelling/fluid accumulation
- Middle ear infection (otitis media)
- Sinus infection (sinusitis)
True or false. Viral infections can be secondary to bacteria causing pharyngitis/tonsilitis.
False. Bacterial infections are secondary to viral
Which viruses most commonly cause pharyngitis and tonsilitis? (3)
- Rhinoviruses
- Echoviruses
- Adenoviruses
What are the most serious consequences of untreated pharyngitis or tonsilitis? (3)
- Rheumatic fever
- Glomerulonephritis
- Chronic tonsillar enlargement
What is atelectasis?
Collapse of a previously inflated lung
What are the 3 subtypes of atelectasis? Which one is not reversible (***).
- Resorption: blockage of airway
- Compression: accumulation in pleural space
- ***Contraction: fibrosis restricts expansion
What is a pulmonary embolism?
Something that blocks the vessels in the lung(s):
Ex: blood clot, air bubble, fatty deposit, other debris
95% of pulmonary emboli are _____
blood clots from large leg veins
Blockage in a vessel causes _____ downstream and _____ upstream.
- Ischemia
- Increased pressure
Approximately 10% of pulmonary emboli result in _______
Pulmonary infarct
What is cor pulmonale?
Right-sided heart failure
Why do large blockages caused by pulmonary emboli kill quickly?
- Increased pressure damages the heart
- Leads to cor pulmonale
Right-sided heart failure leads to ______, while left-sided heart failure leads to ______.
- Cor pulmonale
- Pulmonary hypertension
Pulmonary embolism signals the body to lower _____ and in turn _____.
- Blood pressure
- Cardiac output
What are some reasons for atelectasis with a pulmonary embolism? (2)
- Lack of surfactant
- Reduced movement in response to pain
What are the treatment options for a pulmonary embolism?
- Anticoagulant (e.g. heparin)
- Thrombolytic (risky; only in hospitals)
What vascular changes occur in pulmonary hypertension?
- Medial hypertrophy of muscular and elastic arteries in the lungs: intimal fibrosis
- Plexiform lesions (advanced) that cause dilated thin-walled arteries to rupture
Pulmonary hypertension can be caused by? (6)
- Chronic obstructive or interstitial lung diseases
- Heart disease (left-sided)
- Recurrent emboli
- Autoimmune diseases
- Obstructive sleep apnea
- Idiopathic (80% have genetic basis)
What are the symptoms of pulmonary hypertension?
- Dyspnea
- Fatigue
- End-stage: severe respiratory distress and cyanosis
True or false. Chest pain is rarely seen in pulmonary hypertension.
True
True or false. Pulmonary hypertension is only detectable when it’s advanced.
True
What are the potential treatments for pulmonary hypertension? (3)
- If secondary: treatment of primary disease
- If autoimmune or refractory (untreatable): vasodilators
- Lung transplant
What is Goodpasture syndrome?
- Complex multigenetic disorder
- Pulmonary hemorrhage syndrome
- Autoimmune destruction of alveolar basement membranes
What are the potential treatment options for Goodpasture syndrome?
- Plasmapheresis to remove autoantibodies
- Immunosuppression
What does Goodpasture Syndrome look like histologically in the lungs?
- Intra-alveolar hemorrhage
- Focal necrosis in alveolar walls
- Macrophage accumulation
What is pulmonary edema?
Leakage of fluid into alveolar space
Hemodynamic pulmonary edema is most commonly the result of _______
- Left-sided congestive heart failure
- Increased pressure in LV → Increased pressure in lungs → fluid forced out of the capillaries
What is acute respiratory distress syndrome (ARDS)?
- Severe acute lung injury indicated by:
- Abrupt onset of hypoexemia
- Bilateral pulmonary infiltrates
- Bilateral edema throughout
Explain the pathogenesis of ARDS
- Initiated by macrophages
- Inflammatory mediators damage endothelium and pneumocytes
- Neutrophils invade and debris accumulates (hyalinization)
- Healing starts when macrophages produced TGFβ and PDGF
In ARDS, what are the consequences of damage to type I (squamous) vs type II (cuboidal) pneumocytes?
- Increased permeability
- Decreased surfactant and alveolar collapse
What are the symptoms of ARDS?
- “Heavy” feeling lungs
- Lungs filled with fluid (can be heard on auscultation)
- Stiff lungs due to surfactant loss
- Dyspnea/tachypnea
- Cyanosis/hypoxemia
What are some potential treatments for ARDS?
- 100% oxygen therapy
- Mechanical ventilation
- Treat underlying cause (such as sepsis)
Pneumonia can be caused by what?
- Bacteria
- Viruses
- Mycoplasms
- Fungi
Pneumonia is responsible for ____ of US deaths.
1/6
Does pneumonia cause pulmonary edema or does pulmonary edema cause pneumonia?
Either or both
What is a common risk factor for hospital-acquired pneumonia?
Mechanical ventilation
What typically causes aspiration pneumonia?
- Vomiting
- Markedly debilitated patients, stroke victims, etc.
- Abnormal gag/swallowing reflex
True or false. Chronic pneumonia only occurs in immunocompromised patients.
False. Immunocompetent*
What are some causes of pneumonia? (5)
- Cough reflex suppression/inhibition
- Mucociliary apparatus damage
- Accumulation of secretions
- Decreased macrophage activity
- Edema or congestion (mucus)
What form of pneumonia is often fatal?
Aspiration (necrotizing) pneumonia
What are the two ways bacterial pneumonia can present?
- Bronchopneumonia: opaque spots
- Lobar: entire lobe is opaque
Describe the clinical course of pneumonia
- Rapid onset: fever, chills, cough (mucous with signs of infection)
- Fibrinosuppurative pleuritis: Lung swelling, pleuritic pain, and pleural friction rub
Stage 2 (early red hepatization) of acute pneumonia is indicated by what histologically?
- Neutrophil infiltrate
- Congestion of septal capillaries
Stage 3 (gray hepatization) of acute pneumonia is indicated by what histologically?
Alveolar exudate in air spaces
Stage 4 (resolution) of acute pneumonia is indicated by what histologically?
- Fibromyxoid masses (attempts at rebuilding)
- Macrophages
- Fibroblasts
What virus is responsible for infecting pneumocytes and causing viral pneumonia?
- SARS-CoV
- FIrst time a coronavirus infected somewhere other than the upper respiratory tract
What are the initial symptoms of Severe Acute Respiratory Syndrome (SARS)? (5)
- Malaise
- Myalgia
- Dry cough
- Fever
- Chills
What are some complications that are caused by SARS-CoV-2? (7)
- Pneumonia and trouble breathing
- Organ failure
- New-onset cardiac issues
- ARDS
- Blood clots
- Acute kidney injury
- Additional viral and bacterial infections
Histoplasmosis is caused by what organism?
- Histoplasma capsulatum
- Dimorphic fungus
Describe the gross appearance of histoplasmosis
- Perihilar mass lesions
- Can look like lymphoma or leukemia
Describe the histology of histoplasmosis
- Macrophage aggregates filled with yeast
- Lymph node infiltration
- Granulomas with giant cells
- May develop fibrosis and calcifications
What are the differences between obstructive vs. restrictive diseases?
Obstructive
- Partial or complete obstruction at any level
- Increased resistance to airflow
Restrictive
- Reduced expansion of parenchyma
- Decreased total lung capacity
How are obstructive and restrictive diseases diagnosed in pulmonary function tests?
- Obstructive: decreased forced expiratory volume (FEV)
- Restrictive: decreased FEV and vital capacity
What is emphysema?
- Permanent enlargement of smaller airspaces
- No destruction of walls of smaller air spaces
- No fibrosis
_____ is a complex multigenic disease that increases airway responsiveness to stimuli
Asthma
What are some characteristics of asthma? (3)
- Episodic bronchoconstriction
- Bronchial wall inflammation
- Increased mucus section (which exacerbates 1.)
What is atopic asthma?
Classic hypersensitivity reaction via IgE
What is non-atopic asthma?
Hyperirritability due to viral infection
What drugs are most likely to cause drug-induced asthma?
- Aspirin and other NSAIDS
- Affects balance of cyclooxygenase activity
What are some causes of occupational asthma?
Exposure to:
- Fumes
- Dust
- Gases
- Chemicals
What is chronic inflammatory airway disease?
- Recurrent episodes wheezing, breathlessness, chest tightness, and cough
- Bronchoconstriction (widespread but variable)
- Airflow limitations (partially reversible)
How does recurrent asthma alter airway structure?
- Increased mucus production
- Thickening of basement membrane and smooth muscle
- WBC infiltration
- Increase glandular tissue
What does asthma look like histologically?
- Eosinophil infiltration
- Goblet cell hyperplasia
- Thick basement membrane
- Smooth muscle hypertrophy
In cystic fibrosis, mutations in ______ result in viscous mucus that obstructs passageways
- Cystic fibrosis conductance regulator (CFTR)
- Chloride channel
What are some of the consequences of cystic fibrosis? (5)
- Chronic lung disease
- Pancreatic insufficiency (excess fecal fat)
- Hepatic cirrhosis
- Intestinal obstruction
- Male infertility
______ is caused by particles recognized the body as foreign, but cannot be eliminated
Pneumoconioses
What is black lung?
- Complicated coal workers pneumoconiosis
- Progressive, massive fibrosis
- Black pigment associated with fibrosis (coal)
What are some subtypes of pneumoconiosis?
- Coal workers pneumoconiosis (CWP)
- Silicosis
- Anthracosis
- Asbestosis
True or false. You cannot see silicosis or asbestosis on microscopic analysis.
True
What are some consequences of CWP? (3)
- Pulmonary dysfunction
- Pulmonary hypertension
- Cor pulmonale
Asbestosis increases risk of what type of cancer?
Mesothelioma
What is allergic alveolitis?
- Type of granulomatous disease
- Hypersensitivity pneumonia
- Inflammation in alveoli
What are some consequences of allergic alveolitis? (3)
- Decreased diffusion capacity
- Decreased lung compliance
- Decreased total lung volume
Describe the histology of allergic alveolitis
- Patchy infiltrates in the interstitium
- Loos granulomas without necrosis
- Lymphocyte, plasma cell, and epitheloid macrophage infiltration
- Usually around bronchioles
What is Sarcoidosis?
- Type of granulomatous restrictive disease
- Unknown etiology
What are some histological characteristics of sarcoidosis?
- Non-necrotizing granulomas
- Frequent giant cells
- When chronic, may become scar tissue
What are the possible clinical courses for Sarcoidosis?
- Spontaneous remission
- Steroid therapy
Accumulation of pleural fluid (pleural effusion) can be caused by? (5)
- Incrased hydrostatic pressure (CHF)
- Increased vascular permeability (pneumonia)
- Decreased osmotic pressure (renal disease)
- Decreased intrapleural negative pressure (atelectasis)
- Decreased lymphatic drainage
What is a pneumothroax?
- Air or gas in the pleural space
- Collapsed lung
What causes a spontaneous pneumothorax?
- Idiopathic
- Rupture of alveolus, abscess cavity
What is a flap valve?
- Allows air in but out out
- In tension pneumothorax
