L6 - COPD Flashcards
COPD
chronic and progressive disease characterised by the development of airflow limitation that is not fully reversible and by an accelerated decline in lung function
COPD usually results from…
an abnormal inflammatory response of the lungs to noxious particles or gases
chronic bronchitis
usually seen in COPD
inflammation and excess mucus in the lung
Emphysema
usually seen in COPD
alveolar membrane breakdown
COPD established risk factors
smoking, occupational exposure, a1-antitrypsin deficiency, air pollution
smoking first degree relatives
increases risk 3 fold of COPD
Non-smoking first degree relatives
does not increase risk
COPD genetics
20+ genomic loci associated with lung function (FEV1 levels)
Several of these also associated with COPD susceptibility
a1-antitrypsin deficiency gene
SERPINA1
a1-antitrypsin deficiency genetics
autosomal recessive inherited disorder affecting 1 in 2000-5000 persons in eyrioe
a1-antitrypsin role
coats lungs, protecting from neutrophil elastase
neutrophil elastase
produced by white blood cells too break down harmful bacteria, potentially damaging to the lungs
a1-antitrypsin deficiency
lungs lack coating, so open to damage from neutrophil elastase - lung damage
a1-antitrypsin is trapped in the liver so there is liver damage
?% of COPD patients are or were smokers
90%
Smoking and emphysema mechanism
harmful particles trapped in alveoli
inflammatory response triggered
inflammatory chemicals dissolve the alveolar septum
large air cavity lined with carbon deposits formed
emphysema
COPD pathology
alveoli destruction, excess mucus, narrowed bronchiole, mucus hyper secretion, exudate, mucus inflammation and fibrosis, disrupted alveolar attachments
Airway inflammation
chronic inflammation affecting peripheral airways and lung parenchyma
inflammation increases with disease progression