Transcript The lung and the Upper Respiratory Tract

Restrictive Lung Diseases
Restrictive Lung Diseases
1.
2.
3.
4.
5.
Adult respiratory distress syndrome
Sarcoidosis
Asbestosis
Neonatal respiratory distress syndrome
Idiopathic Pulmonary fibrosis
Acute respiratory distress syndrome
1. Def: Diffuse damage primarily to type 1
pneumocytes + capillary: followed by injury of
type 2 cells and endothelium.
2. Cause: gm - ve Sepsis, trauma, lung infection
etc.
3. Pathogenesis:
1. Diffuse alveolar damage: DAD
2. In E coli infection this DAD is mediated by
free radicals from Neutrophils.
Respiratory membrane
Alveolar sac
Hyaline membrane
ARDS
Morphology:
– Gross: lung is diffusely firm, airless, and
rubbery.
– Micro: Hyaline membrane
Clinical:
– acute dyspnea, cyanosis, hypoxemia.
– X ray: white out : bilateral lung opacity
– Unresponsive to 100% oxygen treatment.
– Mortality is between 30-40%.
Intra alveolar hyaline membrane: fibrin and cell
debris → reduced oxygen diffusion.
Whiteout
End
Neonatal respiratory distress syndrome
Reduced surfactant due to defective
pneumocytes 2.
Clinical similar to ARDS
Sarcoidosis
Sarcoidosis
Definition: disease with non caseating
granulomas, can involve any organ.
Most common presentation.
– Bilateral hilar lymphadenopathy and /or lung
involvement.
Hyper-calcemia is present ( due to high 1,25dihydroxyvitamin D by sarcoid macrophage).
Morphology: Micro
Microscopy :
– Non caseating epithelioid cell granulomas in
all effected organs with giant cells.
– Hilar node: These lympnnode may undergo
calcification: egg shell calcification.
Giant cells contain these structures
Schuamann body
Concentric calcification
Asteroid bodies
Clinical Course of Sarcoidosis
Asymptomatic, discovered incidentally (many
cases).
Dry cough/ night sweat/ fever.
Eye involvement: Mikulicz syndrome: corneal
opacity, blindness.
Skin involvement: erythema nodosum (painful
erythematous plaques or rash).
Sarcoidosis : diagnosis
Final diagnosis is by lung LN biopsy or
biopsy of the skin or eye lesion.
Helpful: CD4/CD8 ratio >2.5 ( in
bronchoalveolar lavage lymphocytes) –
PPD negative.
End
Asbestosis
Cause: Asbestos fibers
Morphology of lung:
Early: diffuse interstitial fibrosis in lower lobe and
fibrous pleural plaque [parietal pleura] .
Late stage: honeycomb lung.
Complications: bronchogenic carcinoma,
mesothelioma.
Asbestos fibers : morphology
Asbestos body or Ferruginous body which
is positive with Prussian blue.
– Amphibole (thin and straight) and
serpentine (curly. Flexible, common ).
– Present in extracellular tissue in lung
interstitium (initial ingested by macrophage
that eventually dies off).
Asbestosis : morphology
Ferruginous body which is positive with Prussian blue.
They arise when macrophages attempt to phagocytose
asbestos fibers.
Late change: “Honeycomb" lung.
It is the end stage of all restrictive lung diseases
Pulmonary hypertension
Pulmonary hypertension → right ventricular
hypertrophy.
Primary
Secondary
More common
1. Multiple pulmonary emboli
2. Increased blood flow ( left-to-right
shunt).
3. COPD and restrictive lung disease :
these cause hypoxia induced
vasoconstriction.
Primary Pulmonary Hypertension
Etiology: unknown
Morphology: plexiform pulmonary angiopathy
and medial hypertrophy.
Secondary Pulmonary Hypertension
Morphology:
– Medial hypertrophy
– Or presence fibrotic organized emboli in
vessels with narrow lumen.
Complications of Pulmonary Hypertension
Right ventricular hypertrophy → Right
heart failure or cor pulmonale
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