Alpha-1 antitrypsin deficiency Flashcards
what type of enzyme is neutrophil elastase?
chymotrypsin protease
effect of neutrophil elastase on lung tissue?
eats elastin
what triggers neutrophil elastase?
- 2 common things
infection & smoking
what is Alpha-1 antitrypsin?
an antiprotease
what does Alpha-1 antitrypsin stop and thus protect?
stops neutrophil elastase
protects lung tissue
A1AT deficiency causes what most commonly?
emphysema
A1AT is caused by mutation to what gene on what chromosome?
SERPINA 1 gene
Chromosome 14
A1AT deficiency is recessive or dominant?
recessive
how does smoking cause emphysema?
Smoke –> inflammatory cytokine –> neutrophils released into lung –> activates neutrophil elastase –> this eats up the lung tissue –> emphysema
which granulocyte activates neutrophil elastase?
neutrophils
how does smoking release neutrophil elastase?
Smoke –> inflammatory cytokine released –> trigger neutrophil release –> neutrophil elastase released
how does smoking increase activity of neutrophil elastase?
smoke –> ROS made –> deactivated alpha 1AT –> increases neutrophil elastase activity.
pt has A1AT deficiency.
main CXR finding?
big black chest
Ix?
- 3 main ones
- state the Ix and +ve finding
Plasma A1AT – low
Spirometry – obstructive low FEV1
CXR – big black lungs
pt has A1AT deficiency.
why might you do CT scan?
look for bronchiectasis.
pt has A1AT deficiency.
asides from lungs what other organ is effected?
what bloods would you do to check this then?
- give +ve results
- 3
liver
LFTs
↑AST, ALT, bilirubin ALP
pt has A1AT deficiency.
main 1st line Mx for everyone?
No smoking
pt has A1AT deficiency.
with lung disease and low A1AT.
lifestyle factors have been addressed.
what is Mx now?
- 3 things
Bronchodilators + physio
IV alpha1-antriypsin given
