24 Interstitial lung diseases Flashcards
Spepta parts
90% Type I pneumocytes
5-10% Type II pneumocytes
Capillary endothelial cells
Ground substance
Interstitial lung disease
Parenchymal disorders that involve the lung interstitium
- Infiltrative diseae
- Diffuse parenchymal lung diseease
- Restrictive lung disease- reduced total capacity 2/2 disease changes
can involve alveolar spaces, septa, and vessels
Types of interstitial lung diseases
Acute- *ARDS Chronic *Fibrosing (pneumoconioses *Granulomatous (sarcoidoses) *Idiopathic interstitial pneumonia (IIP)
Interstitial disease pathogenesis
1) alveolitis- damage to pneumoctes and endothelial
2) Leukocytes> cytokines causing fibrosis
3) fibrosis leads to decr. compliance and expansion
Factors that modulate fibrosis
Chronicity defense effectiveness injury extent BM damage Individual succeptability
Interstitial findings
Dry cough/dyspnea
Bibasalar crackles
bilateral reticulonodular infiltrates
cor polmonale
Pneumoconicoses
Non neoplastic lung diseeease caused by:
* mineral dust, organic and inorganic particulates/ fumes
account for 25% of interstitial lung disease5
Pneumoconicosis pathologic principles
- 1-5um particles dont get past respiratory bronchiole bifurcations
- Smaller reach alveoli and alveolar macs- are phagocytosed
- some are reactive/irritative in and of themselves
Fibrogenic pneumoconicoses
Asbestos
Silicosis
Coal Worker’s pneumconicosis
(berylliosis, thesaurosis-hairspray, etc)
Coal workers Pneumoconicosis
Anthracoticpigment- Coal mine, urban cneters, tobacco smoke
3 forms
-Anthrocosis- assymptomatic with pigment in interstitium and lymph
-Simple
-complicated
Anthrocosis
Asymptomatic with anthrocotic pigment in interstitum and lymph nodes
Simple CWP
- Fibrous opacities <1cm
- upper lobe distribution
- Deposits of coal dust next to respiratory bronchioles
Complicated CWP
- Opacities >1cm
- can have central necroses
- massive fibrosis/black lung
- cor pulmonale
- Caplan syndrome CWP with rheumatoid nodules
- No increase in TB or cancer
Silicosis
Most common occupational disease worldwide
* Quartz crystals engulfed by alveolar macs-> Cytokine induced fibrosis
Morphology
* Nodular opacities with concentric collagen rings *ROPY AND LAMELLAR COLLAGEN
*polarizable quartz particles (shine under light in microscope)
*“Egg shell” calcification in hilar lymph nodes
Complications
*cor pulmonale, Caplan syndrome
*CANCER
*TB
Siliccosis microscopy
Ropey/ lamellar collagen deposition around quartz particles (polarized light reactive)
Asbestos types
Serpetine asbestos
* Curly snake like and flexable fibers - less damaging
Amphibole asbestos
*Straight rigid, friable fibers - can cause bad lung disease and can reach distal lung
Asbestos disease
- respiratory bronchioles and alveolar ducts
- sources
- insulation, roofing material, old building demolition
- Histo
- ferriginous bodies- fbers coated with protein and iron in macs
Asbestos relatted diseases
- Benign pleural plaques - frequnetly on membanous part of diapraghm with pearly nodules, Thickening of pleural area with acellular collagen
- Asbestosis- diffuse interstitial fibrosis
- Bronchogenic carcinoma (20 years later- related to smoking)*
- Mesothelioma
- No risk TB
- Cor pulmonale
- caplan syndrome
Asbestos/ferrigenous bodies
Dumbell like structures within alveolar macs
turn blue with iron stain
Berylliosis
- Beryllium exposure- nuclear airspace industry
- GRANULOMATOUS inflammation- can be mistaken for TB and sarcoidosis
- complicattions
- Cor pulmonale
- Lung CA
Sarcoidosis
- Multisystem granulomatous disease
- 25% of chronic interstitial lung diseeases
- AA:W 10:1, M:F 1:2, 70% less than 40yrs, nonsmokers
- 95-100% with lung involvement
- 80% with lymph incolvement
Sarcoidosis path
- Immune dysregulation
- antigen ? >CD4 cells> Cytokines> Monocyte and hystocytic recruitment- Consolidation and granuloma formaion
- DIAGNOSIS OF EXCLUSION must exclude infectious first.
Sacoidosis signs
skin -Nodular granulomatous lesions -lupis pernio -erythema nodosum eyes -uveitis Liver -Graulomatous hepatitis Other -Enlarged salvitory and lacimal glands -diabetes insipidus -BM and spleen involvment
Lab findings
- ^ACE levels- marker of prognosis and disease response
- hypercalcemia
- increased gammaglobins
- cutaneous aergy- doesnt react to skin antigens (22 cd4 consumption)
- CXR- Bilateral hylar adenopathy, bilateral reticulodular infiltrates
Sarcoidosis prognosis
- many have variavle remission and relapse without tratment
- progressive interstitial fibrosis, cor pulmonale/death in 10%
Hypersensitivity pneumonitis
*Inhaled antigen causing granulomatous interstitial lung disease
Path
*Thype III hypersensitivity
-first exposure- sensitization
-second exposure - immune complex formation and inflammitry
rsponse in lung
-chronic exposure causes IV hypersensitiity and granuloma formation
Hypersensitivity pneumonitis types
- Farmers lung- Actinomycetes
- Silo fillers’ disease
- Inhalation of gases from plant material (oxides of nitrogen)
- Byssinosis
- Cotton, linen, hemp
- Textile factory workers
- “Monday morning blues”
Hypersensitive pneumotitis
- acute, subacute, chronic
- interstital and aveolar infiltrates of inflammator cells, peribronchial accentuation, ill defined granulomas
- GRANULOMAS MELD WITH PARENCHYMA
- diagnosis
- symptoms and CXR, PFTS, Ab reactivity, lung biopsy
Idiopathi pulmonary fibrosis
- USUAL INTERSTIAL PNEUMONIA
- 15% interstitial lung disease cases
- M>F, 40-70 years
- 18-24month duration
- progressing dyspnea, many nonspecific symptoms
- idiopathic repeated injury to lung causes alveolitis and fbrosis
- intestitial fibrosis leading to “honeycombing of the lung”
IIP imaging and morpho
CXR- increase lower bronchiole markings
CT- Honeycombing appearance
Gross- Thick septa and honeycomb type cysts
IIP prognosis
- 50% 5 year prognosis
- progressive fibrosis
- cor pulmonale
Collagen vascular disease
10% of interstitial lung disease
- SLE- (unexplained pleural effusion in young woman)
- RA- fibrosis and pleural effusions with rheumatoid nodules
- Systemic sclerosis- commonest cause of death inscleroderma patients
Sarcoidosis histology
Interstitial granulomas NON NECROTIZING
Around bronchovascular bundles
Follows Lumph tract
Giant cells
SHIT FACED
Sarcoid
Hypersensitivity
Interstitial lung disease
Tumor/TB
Fungal Asbestosis Cancer/Collagen vascular disease Eosinophilic granulomatous Drugs
Sarcoid stages on CXR
1) Huge hilar lymph nodes
2) hilar nodes and bronchial markings
3) Diffuse bronchial marking no nodes
4) Total fibrosis and scarring
ARDS treatment
Small tidal volumes
Peep-16 (doesn’t matter)
Less water given leads to quicker removal from vent
Prone positioning for severe ARDS
