Robert parker Flashcards
Define chronic bronchitis
Chronic inflammation of the bronchi resulting in a productive cough; lasting for at least 3 months over 2 consecutive years.
What is the main cause of bronchitis?
Smoking.
Name 4 infections that can cause chronic bronchitis
Influenza
Staph aureus
Step
Mycoplasma pneumonia
What GI problem can cause bronchitis
GERD
List 4 causes of bronchitis
- Smoking
- Air pollutants
- Infection (staph/strep/mycoplasma/influenza)
- GERD
List 4 complications of chronic bronchitis
- Progression to COPD
- Cor pulmonale
- Epithelial metaplasia -> dysplasia (SCC)
- Bronchial hyper-responsiveness
List 3 morphological features of chronic bronchitis
- Mucus gland hypertrophy (reid index > 0.4) with hypersecretion of mucus
- Goblet cell hyperplasia
- Bronchial inflammation (from release of inflammatory cytokines IL-8)
- Epithelial metaplasia (squamous) -> Dysplasia
outline the pathophysiology of chronic bronchitis
Response to injurious agent e.g. smoking
*Hypertrophy of mucus gland
*Hyperplasia of goblet cells
—-> Hypersecretion of mucus -> mucus plugging.
*Oedema of bronchus due to:
—>release of pro-inflammatory cytokines (IL-8)
—>neutrophil infiltrate to submucosa
—>epithelial cells impaired from releasing usual regulatory substances to modulate inflammation such as angiotensin-converting enzymes/ can’t convert inflammatory substances to inert forms = chronic inflammation + vasodilation.
—> defective mucocilliary function
What is the Reid index
Measures the ratio of mucus gland to thickness to that of bronchial wall - usually < 0.4 and measured at post-mortem.
5 clinical sings of chronic bronchitis
- Cough
- Wheeze (obstruction)
- Crackles (mucus)
- Dyspnea (poor ventilation)
- Cyanosis (shunting)
What type of epithelium lines the bronchus
pseudostratified ciliated columnar
What is meant by carcinoma in situ
Dysplasia confined to epithelium and does not cross the basement membrane.
Define emphysema
Emphysema is an enlargement of the airspaces distal to the terminal bronchiole (i.e. the acinus) due to destruction of the alveolar wall leading to air flow limitation.
Name the 3 types of emphysema, the primary cause of each and their most common locations within the lung
- Centriacinar
–> Proximal acinus affected
–> upper lobes usually
–> smokers - Panacinar
—> Entire acinus affected
—> Lower borders and anterior margins
—> Alpha-1 antitrypsin deficiency - Paraseptal
—> most accentuated on outer margins/adjacent to septa or pleura
—> often adjacent to areas of fibrosis / atelectasis
—> often upper lobes.
What type of emphysema is associated with premature babies?
Interstitial emphysema.
—> associated with positive airway pressure in an attempt to offset affects of infant respiratory distress syndrome.
—> rupture of alveolar walls results in air leakage into the lung interstitium.