Interstitial Lung Disease Flashcards
ILD is an umbrella term for a number of conditions.
What is the interstitium first of all?
What do all these conditions do?
The pulmonary interstitium is a collection of support tissues within the lung that includes the alveolar epithelium, pulmonary capillary endothelium, basement membrane, perivascular and perilymphatic tissues. The pulmonary interstitium can be divided into three zones - axial, parenchymal and peripheral
Affect lung parenchyma due to:
- Chronic inflammation
- Progressive interstitial fibrosis
Causes:
Primary lung diseases - list some - going through later
Multi-system disease - 3
Idiopathic pulmonary fibrosis
Pneumoconiosis
Hypersensitivity pneumonitis
Infections - TB, RSV, PCP
Sarcoidosis
Connective tissue disease - RA, SLE, Ankylosing S
Vasculitis
Causes - Iatrogenic:
Bleomycin:
- What is it?
- Why does it cause fibrosis?
What antiarrhythmic drug may cause ILD? - A
What radiation cause ILD?
What type of immunosuppressant can cause ILD?
What blood thinner and BP drug can cause ILD?
What drug used to treat a UTI causes fibrosis over a long time.? - N
AB used to Rx certain cancers
Bleomycin may upregulate collagen synthesis by modulating fibroblast proliferation through a TGF- response. Excessive collagen deposition may result in severe, irreversible pulmonary fibrosis.
Amiodarone
Ionising irradiation promotes damage to lung epithelium
Methotrexate
Aspirin
ACEi
Nitrofurantoin
Symptoms - 2
Systemic symptoms - 2
Chest pain is rare, so if it is present, what type of cancer does it suggest?
Progressive SOB
Dry cough
Weight loss
Fatigue
Mesothelioma
Signs:
What type of crackles are heard?
When in the breathing cycle are they heard?
Bilateral/unilateral??
What may also be present in asbestosis and hypersensitivity pneumonitis? - 2
There may be no signs in CWP, simple silicosis, and sarcoidosis but CXR with be +ve.
Fine
End inspiratory crackles
Bilateral
Wheeze
Squeaks
Idiopathic Pulmonary Fibrosis (IPF):
How is it diagnosed?
What imaging is needed for diagnosis?
What pattern is seen on spirometry?
Diagnosis of exclusion - it is a common cause of ILD
CT
Restrictive - FEV1/FVC normal or high
Asbestosis:
How long after asbestos exposure does this happen?
Where does it begin before spreading to rest of the lung?
Who must employers inform if their employee has been exposed to asbestos?
The heart border may be ill-defined on CXR due to mediastinal disease. What is this called?
Asbestos-related disease:
- Pleural plaques - what is it? what sign is seen on CXR?
- Pleural fibrosis - what is it?
Shaggy heart border
> 20 yrs (>10 yrs for radiographiic changes)
Lower zones/lobes
HSE - Health and Safety Executive
Asymptomatic pleural thickening on CXR
Holly sign seen on CXR - look up
Pleura becomes stiff
Silicosis and Coal-workers pneumonoconiosis (CWP):
What causes both of them?
Where do these both begin before spreading to rest of the lung?
Simple CWP/simple CHRONIC silicosis:
- What area of the lung are they usually residing in, meaning patients experience very few or no symptoms?
- Does this occur with short or long term exposure?
- For SIMPLE CWP, thy are asymptomatic and have no physical signs. How is it therefore diagnosed?
- What sort of appearance of the hilar lymph nodes is seen on CXR?
Complicated CWP/Accelerated silicosis:
- What do they lead to?
- What sort of exposure is this typical with?
Acute silicosis - Caused by very high conc of silica dust particles:
- Consolidation is seen on XR, but what sign seen in chronic silicosis is not seen here?
What sort of occupations are at risk of above?
What is Caplan’s syndrome?
Egg steel appearance
S - Inhalation of silica particles, which are fibrogenic
CWP - Coal dust accumulates in distal bronchioles, leading to fibrosis
Upper zones Long term (10-20yrs) low exposure
CXR
Progressive massive fibrosis (PMF)
Short term, higher exposures
EGG SHELL APPEARANCE
Foundry fork Stone cutting/carving Mining Quarry workers Sandblasting
A combination of RA + pneumoconiosis that manifests as intrapulmonary nodules, which appear homogenous and well-defined on chest X-ray.
Hypersensitivity Pneumonitis:
What is the body reacting to?
Where does it begin before spreading to rest of the lung?
Another name for it is EAA. What does it stand for?
Causes:
- What job could cause this?
- What type of pet could cause this?
- What other things could cause it?
There are a range - look at slide 63 on presentation
Non-human protein (plant or animal)
Upper lobe
Extrinsic allergic alveolitis
Farmer - exposure to mouldy hay
Bird fancier
Mold (e.g. from AC, humidifiers, ventilators)
Occupational paints and plastics
Hypersensitivity Pneumonitis:
Clinical features:
- Featues of 4-6 hrs post-exposure? - 5
- Features wks to months after exposure?
- Features months to yrs after exposure?
Fever Rigors Dry cough SOB Fine bibasal crackles ==== Productive cough SOB === Leads to fibrosis
Investigations - Chest imaging:
Why does ankylosing S produce upper lobe fibrosis?
- What 2 diseases affect the lower zones first?
- What 1 disease affects middle zones next?
THE REST BEGIN IN THE UPPER LOBE
The pulmonary manifestations of the disease include fibrosis of the upper lobes, interstitial lung disease, and ventilatory impairment due to chest wall restriction, sleep apnea, and spontaneous pneumothorax.
IPF and Asbestosis
Sarcoidosis
Investigations - Chest imaging:
Opacification patterns:
If they look like fine mesh lines (reticular), what does that suggest?
If they have multiple small nodules (reticulonodular), what does it suggest?
IPF
Asbestosis
Connective tissue disease
Sarcoid
Pneumoconiosis (e.g. CWP)
Investigations - CXR:
Findings in IPF?
Findings in asbestosis?
Small, white lungs (reduced lung volume as restrictive)
Basal reticular opacities
https://www.radiologymasterclass.co.uk/gallery/chest/pulmonary-disease/pulmonary_fibrosis
Linear fibrosis
Pleural thickening
https://www.radiologymasterclass.co.uk/gallery/chest/pulmonary-disease/pleural_disease
Investigations - CXR:
Findings in CWP and silicosis?
Findings in sarcoidosis?
Diffuse nodules if simple (also seen in sarcoid and TB)
BHL
Investigations - High-resolution CT:
What is seen in pulmonary fibrosis?
Asbestosis is similar to CXR!!!
What is the shadowing on CT for hypersensitivity pneumonitis described as?
Lower zone reticular fibrosis
Honeycombing and cystic appearance if severe
Ground-glass shadowing - increases opacity without obscuring vessels in mosaic distribution
