Extrinsic Allergic Alveolitis (or HP) Flashcards Preview

Respiratory Diseases > Extrinsic Allergic Alveolitis (or HP) > Flashcards

Flashcards in Extrinsic Allergic Alveolitis (or HP) Deck (9)
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1
Q

what is it

A

infiltration of small airways and alveolar walls with neutrophils followed by T lymphocytes and macrophages - leads to non-caseating granulomas

2
Q

what type hypersensitivity is it

A

type IV (or III)

3
Q

what are the different causes

A
farmers lung - mouldy hay 
malt workers lung - whiskey 
bird fanciers lung - pigeons 
mushroom farm workers - turning mushroom compost 
drugs eg gold, bleomycin, sulphasalazine
4
Q

what are acute symptoms

A
fever (pyrexia)
rigors 
myalgia 
dry cough 
dyspnoea 
crackles (no wheeze)
malaise
5
Q

what are chronic symptoms

A
increasing dyspnoea 
weight loss
exertional dyspnoea 
type 1 resp failure 
cor pulmonale
6
Q

how is acute EAA diagnosed

A

blood - FBC (neutrophilia), ESR (up), ABG
CXR - upper zone consolidation
LFT - reversible restrictive, reduced gas transfer during attack

7
Q

how is chronic EAA diagnosed

A

blood - positive serum precipitants
CXR - upper zone fibrosis, honeycomb lung
LFT - persistent changes
BAL - increased lymphocytes and mast cells

8
Q

how is acute EAA treated

A

remove allergen
give O2
oral prednisolone

9
Q

how is chronic EAA treated

A

allergen avoidance

long term steroids