Pulm Path II Flashcards
Causes of Obstructive airway disease
- Emphysema
- Chronic bronchitis
- Bronchiectasis
- Asthma
- Tumor
- Foreign body
Causes of Restrictive airway disease
- Neuromuscular
- Interstitial/Infiltrative diseases
- Chest wall disorders
How is asthma defined?
-Intermittent and reversible airway destruction
Other features of asthma
- inc. responsiveness of tracheobronchial tree to various stimuli
- chronic bronchial inflammation with eosinophils
- bronchial smooth muscle hypertrophy hyper reactivity
- inc. mucus production
Clinical presentation of asthma
-wheezing, breathlessness, chest tightness, cough
Factors for Atopic Asthma
- Type 1 hypersensitivity reaction with IgE
- begins in early childhood triggered by env. allergens
- Tests: skin reaction to allergen
Factors for drug induced asthma
- several drugs inc. aspirin
- patients with recurrent rhinitis and nasal polyps
- drugs might also induce skin reaction
- chromosome 5q has several susceptibility genes (inc. IL 13 genetic polymorphisms)
Factors for occupational asthma
- Asthma develops after repeated exposure to inciting agent
- CD 14 abnormality
- ADAM 33 20q is a member of metalloproteinase family with polymorphism accelerating bronchial smooth muscle proliferation
What is status asthmaticus?
Hyper inflated lungs
- prolonged bout of asthma lasting for days responding poorly to treatment
- worst outcome of asthma
Histology for asthma
-Curschmann spirals (mucus plugs)
Charcot-Leyden crystals (eosinophil derived crystals)
Clinical definition for Chronic Bronchitis
Persistent productive cough for at least three consecutive months in at least two consecutive years
Epidemiology for Chronic Bronchitis
- smokers
- urban dwellers, smog ridden cities
- most common in middle aged men
Pathology of Chronic Bronchitis
- Hypertrophy of mucus secreting glands
- Goblet cell metaplasia
- Inflammation
- Fibrosis
- May lead to atypical metaplasia/dysplasia of resp. epithelium
What is Reid Index for Chronic Bronchitis?
measures the gland to wall ratio (normally glands are 40% of wall thickness as measured from epithelial basement membrane to cartilage)
Complications for Chronic Bronchitis
- Cor pulmonale
- Infections
- Bronchogenic carcinoma
What is emphysema?
Destruction of walls of airspaces distal to terminal bronchioles, leading to permanent abnormal enlargement of air spaces
Types of emphysema
- centriacinar (centrilobular)
- panacinar (pan lobular)
- Distal acinar (paraseptal)
- Irregular
Characteristics of centriacinar emphysema
- resp. bronchioles
- upper lobes
- male smokers
- coal workers pneumoconiosis
- often associated with chronic bronchitis
Characteristics of pan lobular emphysema
- lower lobes
- alpha 1 -antitrypsin deficiency
- whole acinus
Characteristics of Distal acinar emphysema
- distal acinus
- along pleura and lobular septa
- adjacent to areas of fibrosis, scarring, atelectasis
- can form bullae and lead to spontaneous pneumothorax in young adults
Characteristics of irregular emphysema
- acini irregularly involved
- associated with scarring/healed inflammatory lesions
- mostly asymptomatic
Pathogenesis of Emphysema
- mild chronic inflammation
- overproduction of protease in relation to antiprotease
Alpha-1 Antitrypsin deficiency Characteristics
expressed codominantly on Pi locus of chromosome 14
- normal is PiMM
- worst form is PiZZ
What is Bronchiectasis?
Permanent dilatation of bronchi and bronchioles caused by destruction of the muscle and elastic tissue caused by chronic necrotizing inflammation
Etiology of Bronchiectasis
- Obstruction
- Infection
- Congenital/Hereditary (cystic fibrosis, kartagener’s syndrome, Immunodeficient states)
- Other (Rheumatoid arthritis, lupus
Cystic Fibrosis
- severe bronchiectasis
- defect in CFTR on chromosome 7 (delta F508) leading to accumulation of viscous secretions obstructing airways and infections
Kartagener syndrome
- Sinusitis, bronchiectasis, situs inversus, infertility
- caused by primary ciliary dyskinesia
- autosomal recessive with variable penetrance
- absence or shortening of dynein arms
Complications of Bronchiectasis
- Resp. insufficiency
- cor pulmonale
- brain abscesses
- amyloidosis
