Respiratory Disease Flashcards
Diagnosis of COPD
Persistent airflow limitation demonstrated by:
FER = FEV1/FVC = <0.7
GOLD Classification for COPD severity:
Takes into account symptom severity (based on mMRC score, or CAT score) and exacerbation frequency.
0 or 1 (not leading to hospital admission)
A
B
2 exacerbations, or 1 leading to hospital admission.
C
D
Principals of management in COPD?
Think about it in terms of symptom symptoms reduction and exacerbation reduction.
Reducing Symptoms:
LABA and LAMA effective for symptom reduction (and exacerbation therapy):
- LAMA is more effective than LABA for monotherapy (therefore tiotropium first line)
- combination LAMA/LABA therapy is more effective than mono-therapy but more expensive.
Preventing Exacerbations:
- Once someone has exacerbated, monotherapy no longer sufficient.
- 1st line is LABA/ICS or LABA/LAMA
- Most people will get LABA/LAMA, unless there is a reason to give steroid:
- Eosinophil count >0.3
- Asthma history
Once hospital admission – Triple therapy.
Contra-indications for smoking cessation therapy?
NRT
- Avoid in unstable coronary heart disease, ok to use in stable disease.
Vareniclne
- avoid in patients with suicidal ideation
Bupropion
- Avoid in bipolar disorder
Options for smoking cessation?
Combination NRT with behavioural intervention is more effective than either alone.
Combination NRT RR 1.34
Varenicline (nicotine receptor partial agonist)
- Avoid with unstable psychiatric symptoms and suicidal ideation. Ok in stable psychiatric disease.
Bupropion
- Similar efficacy to mono-therapy NRT, less efficacy than varenacline
- Preferred in those with mild untreated depression, avoid in bipolar disease and seizure disorders.
Basic steps to interpret spirometry?
1 - is there obstruction? FER <0.7
2 - is there restriction? FVC < LLN
This is all you can answer from basic spirometry.
Obstructive
Restrictive
Mixed
Gas Transfer and Diffusing Capacity
DLCO = gas exchange (total)
VA = Alveolar volume
KCO = index of efficiency of CO transfer (DLCO per unit alveolar volume)
Asthma Definition
History of respiratory symptoms (wheeze, SOB, chest tightness, cough
That VARY over time and in intensity
Together with variable expiratory airflow limitation
Investigating asthma
Mannitol bronchoprovocation testing
- highly specific, used to rule in.
Methacholine bronchoprovocation testing
- highly sensitive and used to rule out. Methacholine more provoking than mannitol.
Testing for asthma:
Step 1 - Spirometry
If normal spirometry without bronchodilator response. Move to Bronchoprovocation testing,
Step 2 - DIrect Methacholine testing looking for fall in FEV1 >20%, highly sensitive, good for ruling out
Step 3 Indirect Mannitol or hypertonic saline, testing looking for fall in FEV1>15%
Exercise or eucapnic voluntary hyperventilation.
Other:
- FeNO
Eosinophilic pneumonia
Ket feature is rapid radiological clearance with steroids.
SYGMA Trial in Asthma
- Symptoms controlled best with regular ICS.
- Symptoms controlled better with PRN ICS/LABA (eformoterol = fast acting LABA) than SABA
- ICS/LABA was non-inferior to regular ICS for reduction in exacerbations.
Therefore intermittent LABA/ICS is the first line, rather than SABA.
What do when not controlled on regular ICS?
OPTIMA Trial - increased dose ICS vs ICS/LABA combination therapy.
Combination therapy superior to increasing dose of ICS.
Biologic therapy options for asthma?
Omalizumab - Anti IgE
Mepolizumab - IL 5
Benralizumab - IL5R
Dupilimab - IL 4 / 13
Tezepelumab - targets TSLP (thymic stromal lymphopoitin)
Classification for asthma phenotypes?
T2 high:
- Allergic: IgE, Aspergillis fumigatus IgE
- Eosinophilic: Blood and sputum eosinophilia, FeNO
T2 Low:
- Lack of T2 inflammation
Omalizumab
Anti - IgE
- SC injection every 2-4 weeks
- Benefit in patients: Elevated IgE + Atopy + Asthma
Major benefit in allergic asthma:
IgE needs to be elevated 30-700IU/ml with positive skin prick testing to at least 1 antigen.
Mepolizumab and Benralizumab
Mepo (IL 5) 4 weekly injection and Benza (IL 5 R) 8 weekly injections.
Dupilimab
IL 4 + IL 13
Fortnightly injection
Also used for eczema.
Tezepelumab
Up stream TSLP inhibitor.
Management of T2 Low severe asthma
Inflammation is often neutrophilic.
Treatment options more limited.
- LABA and LAMA
- Theophylline
- ?Macrolides
Radiological features of UIP
Definite UIP needs all 4 criteria:
1 Honeycombing
2 Reticular opacity with sub-pleural and basal predominance.
3 Traction bronchiectasis
4 And NO atypical features
ILD Categories:
ILD of known causes (can usually diagnose on history)
- Dusts, CTD, hypersensivity pneumonitis, radiation induced, drug induced.
Granulomatous ILD - sarcoidosis
Idiopathic ILD
- Smoking related: respiratory bronchiolitis ILD, desquamative
- Acute/Subacute: cryptogenic organising pneumonia, acute interstitial pneumonia
- Chronic/Fibrosing: IPF, idiopathic NSIP
Other
Treatment of IPF?
Prednisolone/Azathioprine/NAC associated with increased death.
Anti-fibrotic therapy (nintedanib and pirfinedone)
- IPF diagnosed with MDM
- FVC>50%
- FER > 0.7
- DLCO > 30%
- No other causes.
Nintendanib
MOA: multiple tyrosine kinase inhibitor
Slows rate of decline in FVC
S/E:
- Diarrhoea
- Nausea
- LFT derangement
Pirfenidone
MOA: Inhibits TGF beta and fibroblast proliferation.
Slows rate of FVC decline
S/E
- Rash
- Nausea
- Diarrhoea
NSIP Pattern
GGO
Reticular opacity, but diffuse and can have sub-pleural sparing.
Traction Bronchiectasis
NO honeycombing.
NSIP DDx:
CTD
HIV
Drugs (amiodorone, MTX, flecainide, nitrofurantoin)
Hypersensitivity pneumonitis
Idiopathic NSIP
Treatment of NSIP:
Considered treatable with corticosteroids.
Hypersensitivity Pneumonitis
Not a single disease.
Need a history of exposure + clinical features.
HRCT features:
- Centrilobular nodules or GGO
- mosaic hyper-attenulation