Singh Pathology of Respiratory System #2 Flashcards
In restrictive lung disease what will the FEV1/FVC ratio be, what will TLC be, and what will the FVC be in comparison to normal?
- FEV1/FVC will be normal
- everything is reduced so ratio stays normal
- TLC decreased
- FVC will be reduced
- Volume restriction
How will the FEV1/FVC ratio, TLC and FEV1 present with an Obstructive lung disease?
- Low FEV1
- Low ratio
- Increased TLC
- Decreased flow and trapped air
How do you diagnose chronic bronchitis?
Persistent cough with sputum production for 3 months out of 2 consecutive years
What is the pathophysiologic mechanism behind chronic bronchitis?
Mucous gland hyperplasia causing damage to airway epithelium
What are the five complications of chronic bronchitis?
- Bronchiectasis
- Hypoxia
- Squamous metaplasia leading to dysplasia leading to carcinoma
- Pulmonary hypertension and cor pulmonale
- Death from infection
What is emphysema?
- irreversible airspace enlargement occurring distal to terminal bronchial
- Obstructive Lung Disease
____emphysema due to smoking is an advanced obstructive lung disease in continuity with chronic bronchitis
Centrilobular emphysema due to smoking is an advanced obstructive lung disease in continuity with chronic bronchitis
Why is emphysema due to smoking centrilobular?
- Obstruction from chronic bronchitis constricts the terminal bronchiole so dilation starts at the respiratory bronchiole and moves distally from there as the disease advances
How will emphysema present on CXR?
- Enlarged lungs with flattened diaphragm
- Barrel chest with increased AP diameter
Clinically how will emphysema present?
- Diminished breath sounds with prolonged expiratory wheezes
- Barrel Chest
- PFT’s show restrictive pattern
- Decreased TLC
- Decreased FVC
- FEV1/FVC
How will Chronic bronchitis present in a patient? (“blue bloaters”)
- Overweight and cyanotic
- Elevated hemoglobin
- Peripheral edema
- Rhonchi and wheezing
How will emphysema present? (“pink puffers”)
- Older and thin
- Severe dyspnea
- Quiet chest
- XR with hyperinflation and flattened diaphragm
Why does Hgb increase in chronic bronchitis?
- Smoking related exposure to CO creates carboxy hemoglobin shifting the oxygen dissociation curve to the left
- This reduces oxygen carrying capacity and compensation is to make more hemoglobin
What is the function of alpha 1 antitrypsin & where is it made?
- coats lungs and protects them from neutrophil elastase
- synthesized in liver and secreted into blood to inhibit neutrophil elastase
Genetics behind alpha 1 antitrypsin deficiency? How do you diagnose?
- encoded by Pi gene on chromosome 14
- Z allele is associated with decreased alpha 1 AT
- Homozygous PiZZ individuals have this deficiency
- Serum testing is primary means of diagnosis
Complications of Emphysema?
- Pneumothorax with lung collapse
- Pulmonary htn and cor pulmonale
- CAD
- Resp failure
3 components that make up Asthma?
- Recurrent airway obstruction with reversible component
- Airway hyper responsiveness
- Airway inflammation
Atopic extrinsic asthma characteristics?
- ⅔ of all patients
- Any age but typically childhood
- Fhx of asthma
- Elevated IgE
- Allergens can trigger
Non atopic intrinsic asthma characteristics?
- ⅓ of all patients
- Often older patients
- Normal IgE
- Triggers are cold exercise and infection
What are the bronchoconstriction mediators to asthma?
- Leukotrienes C4, D4, E4
- Histamine
- Prostaglandin D2
- Ach
What kind of damage occurs with a1 AT deficiency?
Pan acinar emphysema due to the alveoli being bathed in blood carrying neutrophil elastase
What are the bronchoconstriction mediators to asthma?
- Leukotrienes C4, D4, E3
- Histamine
- Prostaglandin D2
- Ach
What causes mucus secretion in asthma?
Leukotrienes C4, D4, E4
What causes increased vascular permeability in asthma?
C4, D4, E4
What recruits inflammatory cells in asthma?
Interleukins
What are the long term effects of uncontrolled asthma?
- Progressive structural changes to airways with fibrosis, smooth muscle hyperplasia and increased goblet cells and submucosal glands
What is Status Asthmaticus?
- Unremitting potentially fatal asthma attack
- Bronchial occlusion by thick mucus
- Curschmann spirals coiled mucus plugs
- Eosinophils and their breakdown products called charcot leyden crystals
What is Aspirin Sensitive asthma associated with?
- Asthma, Nasal polyps, & recurrent rhinitis ( samter’s triad)
How does Aspirin sensitive asthma occur?
by blocking Cyclooxygenase you activate the 5-lipoxygenase pathway which increases Leukotrienes C4-E4
What is Bronchiectasis?
- Permanent dilation of airways due to inflammatory destruction
- dilated bronchi extend to pleural surface
What is Kartagener’s syndrome (primary ciliary dyskinesia)?
What results?
- Dysfunction of dynein arm of microtubules
- Microtubules are needed for movement of cilia and flagella
- Triad of
- Sinusitis
- Bronchiectasis
- Situs Inversus
- relies on motile cells to rotate
- also see male infertility due to lack of flagella on sperm
What happens in Allergic Bronchopulmonary Aspergillosis?
- Aspergillosis sits in the airways and doesn’t invade, but IgE is increased leading to thick dark mucus in the bronchi
- Associated with bronchiectasis in advanced disease
- Positive skin test and background of asthma or CF
