Hypersensitivity Pneumonitis Flashcards
What is hypersensitivity Pneumonitis?
A combined type 3/4 hypersensitvity reaction to foreign antigens leadin to formation of soft centriacinar epitheloid granulomas and intersitial pneumonitis with fibrosis.
What is a common name for hypersensitivity pneumonitis?
Bird Fancier’s Lung
What are the symptoms of HP?
Acute:
- Fever & chills
- Dry Cough
- Myalgia
- Crackles
- Tachypnoea
- Wheeze
Chronic:
- Malaise, fatigue, weight loss
- SOB, Cough
- Tachypnoea
- Type 1 Resp. failure.
What tests can be done for HP?
CXR
Lun function Tests looking for restrictive pattern.
Biopsy
What would a HP biopsy show?
expansion of the interstitium along with some multinucleated giant cells or granulomas.
What antigens commonly cause HP?
Bird/Animal proteins
Funghi
Chemicals
How can we treat HP?
Avoid the antigen
Corticosteroids (e.g. prednisolone) can help symptoms.
How does chronic unstopped HP end?
Fibrosis ending in end-stage honeycomb lung.