T4 - Occupational lung disease Flashcards
does occupational lung disease have a long or short latency period?
long
give four examples of OLD
COPD, mesothelioma, occupational asthma and pneumoconiosis
that is the principle cause of pneumoconiosis
dust
what is the FEV1:FVC ratio in restrictive lung disease?
> 70%
what is the FEV1:FVC in obstructive lung disease?
<70%
which OLD results in massive fibrosis, activation of alveolar macrophages and stiff lungs?
pneumoconiosis
what type of pneumoconiosis causes fibrotic lung disease, restriction, eggshell calcification of LN and scarring?
silicosis
what is the increased scarring in silicosis a risk factor for?
TB and lung cancer
give three main symptoms of pneumoconiosis
dyspnoea, cough and cor pulmonale
what is the key diagnostic feature seen on CXR for asbestosis?
pleural plaques
what are two benign manifestations of asbestosis?
benign pleural effusion and pleural thickening
what is restricted spirometry in asbestosis a sign of?
pleural thickening
what can asbestosis lead to and what are two key features of this?
intersistial lung disease
- reduced lung function
- reduced gas transfer
what are two malignant manifestations of asbestosis?
Lung cancer and mesothelioma (malignancy of pleura and peritoneum)
give five features that should direct to a diagnosis of mesothelioma
1) pleural plaques on CXR
2) chest pain
3) weight loss
4) dyspnoea
5) unilateral pleural effusion
what are the two types of occupational asthma?
1) caused by workplace exposure (didn’t have asthma before)
2) aggravated by workplace exposure (pre-existing asthma that has worsened)
what is challenge testing for occupational asthma?
expose a patient to an agent that is thought to be the cause after a placebo exposure day then monitor spirometry
what are the requirements for a patient to undergo challenge testing?
patient needs to be stable and not on bronchodilators
what are differential diagnoses for OA?
COPD, HF, interstitial lung disease
who should be considered for having OA?
any patient presenting with asthma in their adult life
what two agents can allergic OA be due to?
low or high molecular weight agents
what are two key features of high mw agents that cause allergic OA?
1) account for 80-90% of cases
2) IgE dependent
what test is done for high mw agent causes of allergic OA?
skin prick or allergy test for flour, animals, latex and enzymes
are low mw agents for allergic OA IgE dependent?
no
