Pulmonary Fibrosis Flashcards
(31 cards)
What are interstitial lung diseases?
What are the 2 main types?
interstitial lung diseases (ILD) affect the lung interstitium
this is the space between the alveolar epithelium and capillary endothelium, causing inflammation and fibrosis
the 2 main types are sarcoidosis and pulmonary fibrosis
Who tends to be affected by sarcoidosis?
How easily does it usually resolve?
sarcoidosis tends to affect younger adults and can also affect any other organ system in the body
in 90% of cases the lungs are involved
it has a more benign prognosis and resolves by itself in many cases
Who tends to be affected by pulmonary fibrosis?
What is the prognosis like?
pulmonary fibrosis tends to occur in older adults
it causes significant mortality and morbidity
What are the 5 different types of interstitial lung disease?
- idiopathic pulmonary fibrosis
- sarcoidosis
- pneumoconiosis
- drug-induced ILD
- hypersensitivity ILD
What 2 main drugs are associated with drug induced ILD?
amiodarone and methotrexate
What is the incidence of ILD?
the incidence of all ILDs combined is about 30 per 100,000
What symptoms does someone with ILD tend to present with?
What symptoms are rarely present?
- often slowly progressive
- dry cough
- progressive shortness of breath
wheeze, haemoptysis and chest pain are rare
What clinical signs may be visible for someone with ILD?
- may have clubbing of the fingers
- may have diffuse inspiratory crackles
What investigations are needed to diagnose ILD?
- abnormal CXR
- restrictive respiratory pattern of spirometry
What are the 3 features by which pulmonary fibrosis is characterised by?
pulmonary fibrosis is the end result of many respiratory conditions that is characterised by:
- scar tissue in the lungs
-
decreased compliance giving a RESTRICTIVE pattern in pulmonary function tests
- FEV1 / FVC ratio > 80%
- end stage is “honeycomb lung” where cystic spaces develop in fibrotic lungs
How can pulmonary fibrosis be classified according to involvement?
-
localised
- e.g. following unresolved pneumonia
-
bilateral
- e.g. in TB
-
widespread
- e.g. in idiopathic pulmonary fibrosis or pneumoconiosis
What are the “four D’s” for remembering the main clinical features of fibrotic lung conditions?
- Dry cough
- Dyspnoea (progressive)
- Digital clubbing
- Diffuse inspiratory crackles
although many diseases can cause pulmonary fibrosis, patients tend to present with SOB and changes on CXR
What is idiopathic pulmonary fibrosis?
What age range tends to be affected?
a relatively rare, progressive, chronic pulmonary fibrosis of unknown aetiology
it typically occurs in patients 45-65 years and involves the lower lobes
the peak age of onset is in patients aged 50-60
What are the 4 main features of idiopathic pulmonary fibrosis?
- dry cough
- progressive breathlessness
- significant weight loss
- fatigue / malaise
What type of cell is increased in idiopathic pulmonary fibrosis?
Which region of the lung tends to be affected?
the alveolar walls are affected predominantly in the subpleural regions of the lower lobes
there is an increased number of chronic inflammatory cells in the interstitium
Over time, what will pulmonary fibrosis progress to cause?
the disease progresses over time to cause:
- pulmonary hypertension
- cor pulmonale
- and type I respiratory failure
What are the 3 signs that will be present on clinical examination in someone with idiopathic pulmonary fibrosis?
What is the prognosis like?
- reduced chest expansion (both sides)
- end inspiratory crackles
- clubbing (in 2/3 patients)
it has a very poor prognosis with median age of survival being 3-4 years
What blood tests are performed in idiopathic pulmonary fibrosis?
- FBC will show raised ESR
- 50% of patients are positive for rheumatoid (Rh) factor
- 30% of patients are ANA positive
What would a CXR look like in someone with idiopathic pulmonary fibrosis?
- irregular, reticulo-nodular shadows, often in the lower zones
this is called the reticulonodular pattern
- the CXR is often normal
What would be seen on a CT scan of someone with idiopathic pulmonary fibrosis?
- usually a “high resolution CT” is performed
- ground-glass opacification
- honeycombing
- mosaicism
What is meant by “ground glass opacification”?
an area of hazy opacification (X-ray) or increased attenuation (CT) that does not obscure the underlying bronchial structures or pulmonary vessels
it occurs due to air displacement by fluid, airway collapse, fibrosis or a neoplastic process
What will lung function tests show in someone with pulmonary fibrosis?
a restrictive pattern
What will an ABG show in someone with pulmonary fibrosis?
What procedure is needed to confirm histological diagnosis?
- ABG will show hypoxaemia
-
transbronchial or open lung biopsy is needed to confirm histological diagnosis
- this also assists in defining the type of ILD that is present
