Revision Flashcards
(21 cards)
What are the two types of Interstitial Lung Disease?
Acute response
Chronic response
What is the most common acute response restrictive lung disease?
DADs - diffuse alveolar damage
What are the two stages of DADs
exudative
proliferation
what does the histology of DADs look like ?
Fibrin - light pink layer that coats the inside of the alveoli
Epithelial and Fibroblast proliferation (messy and chaotic)
Denuded basement membranes
What are the three types of response in chronic response restrictive
Granulomatous response
Usual Interstitial pneumonitis
Non specific interstitial pneumonitis
What are the two types of granulomatous interstitial lung disease
Sarcoidosis
Hypersensitivity pneumonitis
Sarcoidosis:
Clinical Presentations
Self limiting:
Acute arthralgia (joint pain)
Erythema Nodosum
Bi lateral hilar lymphadenopathy
Coticsoteriods:
Abnormal CXR
SOB
Cough
Sarcoidosis:
Histology
Epithelioid and giant cell granulomas
Variable associated fibrosis
Necrosis and ceseation is very rare
Sarcoidosis:
Investigations
History and examination CXR - consolidation of hilar glands - fibrosis - fluffy outline of heart Eye exam CT (looks like snow storm) Bronchoscopy FBC and urinalysis - elevated serum Ca+ and ACE Surgical biopsies not usually done
Sarcoidosis:
Treatment
Mild - no treatment
Erythema nodosum/arthralgia - NSAIDs
Skin lesions/cough - Steroids
Cardiac/neurological/eye disease - systematic steroids
Hypersensitivity pneumonitis:
Aetiologic Antigens
Thermophilic actinomycetes
- farmers lung
- micropolyspora faeni
thermoactinomyces vulgaris
Bird/animal proteins
- pigeons
Fungi
-aspergillus spp
Chemicals
Hypersensitivity pneumonitis: Clinical presentation (acute and chronic)
Acute: fever dry cough crackles tachypnoea wheeze chills 4-9 hours after Ag exposure
Chronic: malaise SOB cough crackles some wheeze maybe clubbing if advanced
Hypersensitivity pneumonitis:
Histopathology
Upper zone disease!!
Soft centracinar epitheloid granuloma
Foamy histiocytes
Bronchiolitis obliterans
State the most common forms of usual interstitial pneumonitis
Idiopathic Pulmonary Fibrosis
Crypytogenic Fibrosing Alveolitis
Connective Tissue Disease
IPF:
Aetiology
Unknown cause! most are idiopathic
connective tissue disease -rheumatoid disease -esp scleroderma drug reaction post infection industrial exposure (asbesto)
IPF:
Histology
Basal and Posterior Fibrosis!!!
o Type II pneumocyte hyperplasia
o Proliferating fibroblastic foci
-fibroblasts producing a lot of fibrous protein
o Smooth muscle and vascular proliferation
o Evidence of new and old injury (cells in different stages of evolution)
IPF:
Clinical signs
Dyspnoea Cough Basal crackles Cyanosis Clubbing
IPF:
Prevalence
Poor prognosis
Progressive disease
Age > 50
M > F
IPF:
Treatment
OAF (oral anti-fibrotics)
- pirfenidone
- niotedanib
Palliative care
Some response to steroids
Surgery
-transplant (healthy liver, good bone quality, age, fitness, good psychosocial situation)
IPF:
Investigations
CXR
- fluffy outline of heart
- consolidation
What does all interstitial lung disease result in?
Fibrosis
End stage honey comb lung
Restrictive pattern of restrictive lung disease
Reduced lung compliance
-The elastic is still present tin the alveoli walls but there is a lot more extra tissue such as fibrous protein which prevents the alveoli from expanding as much and hence decreasing the compliance.
Air can’t get into lungs at normal volume so O2 cannot get into the blood at the same rate but exhalation is not affected so CO2 can leave the lungs. Therefore there is a normal partial pressure of CO2 but usually a low partial pressure of O2.
