1. Chest (Diseases of Interstitial Lung (Cystic lung disease, Pneumoconioses, ILDs)) Flashcards
Pulmonary LCH (Langerhans Cell Histiocytosis) - progression (3)
Starts with centrilobular nodules w/upper lobe predominance,
Nodules cavitate into cysts, from thin to thick walled.
“Bizzare shaped cysts” when multiple cysts merge together.
Pulmonary LCH - Trivia (3)
Half of cases resolve spontaneously (if you stop smoking).
Spares costophrenic angles.
Affects smokers in 20s-30s.
What spares the costophrenic angles? (2)
LCH
Hypersensitivity Pneumonitis
Lymphangiomyomatosis (LAM) - trivia (2)
Seen in women of child-bearing age (oestrogen dependent)
Associated with tuberous sclerosis.
LAM - anatomy (2)
Thin walled cysts, uniform distribution.
Association with chylothorax.
LAM - Rx/prognosis
Usually progressive, despite hormonal therapy (tamoxifen)
Birt Hogg Dube - features
Thin walled, oval cysts.
Birt Hogg Dube - trivia (2)
Associated with renal findings (bilateral oncocytomas, chromophobe RCCs).
Associated with skin findings.
Lung cysts - comparison (3)
LCH: Bizzare shape, thick walled
LAM: Round, thin walled
BHD: Oval, thin walled
Lymphocytic Interstitial Pneumonitis (LIP) - Features (3)
Benign lymphoproliferative disorder with lung infiltration.
Cysts usually thin walled, deep within the lung parenchyma, predominantly Sjogrens.
Other causes have ground glass or nodules
LIP - trivia (2)
Associated with autoimmune diseases (Sjogrens, SLE, RA).
Associated with HIV (kids)
PCP - trivia
Commonest opportunistic infection in AIDS
PCP - imaging (4)
Ground glass appearance, predominantly hilar and mid-lung zones.
Pneumatoceles present in 30%.
Cystic form is more common when receiving aerosolized prophylaxis (b/l thin walled cysts, predominantly upper lung).
Gallium positive (diffuse uptake), Thallium negative.
AIDS + Ground Glass Lungs
PCP
Emphysema - definition (3)
Permanent enlargement of airspaces distal to terminal bronchioles,
accompanied by alveolar wall destruction,
without clear fibrosis
Emphysema - Imaging (CXR) (5)
Often only indirect signs on CXR until very bad.
Flattening of hemidiaphragm considered most reliable sign.
AP diameter increases.
Retrosternal clear space becomes larger.
Paucity of, or pruning of blood vessels
Emphysema - Types
Centrilobular.
Pan-lobular.
Para-septal.
Centrilobular emphysema - trivia (3)
By far most common.
Common in asymptomatic elderly.
Associated with smoking.
Centrilobular emphysema - imaging (3)
Apical to basal gradient (favour upper zones).
Focal lucency centrally within secondary pulmonary lobule, with central dot representing bronchovascular bundle (Central Dot Sign is buzzword).
Pan-lobular emphysema - imaging (2)
Favours lower lobes.
More uniform distribution through the secondary pulmonary lobule.
Pan-lobular emphysema - trivia (3)
Associated with alpha-1 antitrypsin deficiency.
Associated with Ritalin.
Patients present in 60s-70s (earlier if smoker)
Para-septal emphysema - imaging (4)
Adjacent to pleura and septal lines.
Peripheral distribution within the secondary lobule.
Small focal lucencies up to 10mm.
Looks like honeycombing but less than 3 layers.
Saber sheath trachea (2)
Diffuse coronal narrowing of the trachea, sparing extrathoracic portion.
Pathognomonic for COPD.
Main PA larger than Aorta associated with.. (2)
Associated with worse outcomes in COPD.
Pulmonary HTN caused by emphysema.
Vanishing lung syndrome - features (4)
Idiopathic cause of giant bullous emphysema.
Results from avascular necrosis of lung parenchyma and hyperinflation.
Defined as bullous disease occupying at least 1/3 hemithorax.
Favours upper lobes