Immunologic Lung Disease Flashcards
(23 cards)
If you had to associate Allergic Bronchopulmonary Aspergillosis with one branch of the adaptive immune system, which one would it be?
Th2 - Type 2 T helper cells
If you had to associate Hypersensitivity Pneumonitis with one branch of the adaptive immune system, what would it be?
Th1 - Type 1 T helper cells
Symptoms of Hypersenstivity Pneumonitis?
Cough, dyspnea, and fever. Notably, with exposure to antigen.
How can you test for IgG against an allergen?
Why not use an ELISA?
Ouchterlony test - in a gel, 3 wells. Patient’s serum in center well. Allergen in side well. Control antigen (or anti-IgG in another well). If patient has antibodies against the allergen, a line of precipitate will form between the allergen well and the serum well.
(this allows you to test for Abs against any allergen you can isolate - not just antigens for which you already have antibodies/ELISAs developed)
3 stages of hypersensitivity pneumonitis?
HRCT findings of each?
Acute - ground glass infiltrates (showing inflammation).
Subacute - nodules and air-trapping.
Chronic - fibrosis, honeycombing, emphysema.
What’s the predominate immunopathological finding in acute, subacute, and chronic hypersensitivity pneumonitis?
Acute: Th1 lymphocyte response, immune complexes.
Subacute: Granulomas.
Chronic: Fibrosis.
PFTs in hypersensitivity pneumonitis?
How about bronchiolar lavage?
Typically restrictive, but can be normal.
Bronchiolar lavage increased total cells, increased T cells, CD4/CD8 >1
6 diagnostic criteria for hypersensitivity pneumonitis?
the first 2 are most important
- Exposure to antigen.
- Precipitating antibodies to known antigen. (Ouchterlony test).
- Recurrent episodes.
- Inspiratory crackles on PE.
- Symptoms occur 4-8 hours after exposure.
- Weight loss.
Management of hypersensitivity pneumonitis? (most important points)
Stop exposure to antigen.
Treat acute phase with glucocorticoids.
(if subacute phase, more / longer steroid treatment..)
Fix it before there’s permanent damage.
4 symptoms / findings of allergic bronchopulmonary asperigillosis (ABPA) - or more broadly, allergic bronchopulmonary mycosis?
Asthma.
Pulmonary infiltrates.
Mucus plugging.
Proximal bronchiectasis.
5 diagnostic criteria for ABPA?
Asthma. Central bronchiectasis. (important!) Immediate cutaneous reactivity to Aspergillus. Elevated total serum IgE. Elevates IgE or IgG to Aspergillus.
PFT findings in ABPA?
Obstructive (it’s considered asthma..).
1/2 of patients respond to bronchodilators.
Air-trapping.
Reduced DLCO (uncommon).
More specific treatments for ABPA? (i.e. other than normal asthma treatment)
Antifungals.
Anti-IgE (omulizumab - Zolair).
-though it’s unclear how effective these are.
What are some features of the histology of vasculitis?
Fibrinoid necrosis.
Lymphocytic infiltrate.
Several skin manifestations of vasculitis?
Palpable purpura - hemorrhages.
Ulcers, gangrene, saddle nose deformity - secondary to ischemia.
Granulomatous polyangitis (GPA, no longer aka Wegener’s vasculitis) can affect many organs. Which does it most commonly affect?
Lungs - upper airways (73%) more so than lower airways (48%).
Joints (32%).
Kidneys (20%).
Eyes, skin, nerves less commonly.
4 upper airway manifestations of GPA?
Sinus disease.
Epistaxis.
Septal perforation.
Subglottic stenosis -> dyspnea, stridor, voice change, cough.
How can GPA affect the lungs?
With cavities, hemorrhage, inflammation, stenosis, and endobronchial disease.
Which ANCA (anti-neutrophil cytoplasmic antibody) is GPA associated with?
C-ANCA (cytoplasmic).
As opposed to P-ANCA, perinuclear.
4 clinical aspects of the diagnosis of GPA?
1 helpful lab value?
Nasal inflammation.
Abnormal chest CT - nodules, fixed infiltrate, cavities.
Abnormal urinary sediment.
Granulomatous inflammation of biopsied blood vessel.
Positive C-ANCA points toward GPA.
(also positive anti-Proteinase-3)
T cell subtype associated with GPA inflammation?
Th1 - with IFNgamma, TNFalpha, etc.
Immune cells involved in GPA?
CD4s, B cells, PMNs
What do PFTs show in a patient with GPA?
Restrictive lung disease with reduced D(L)CO.
