occupational lung disease Flashcards
what information do you need to get when taking an occupational history?
- type of mineral
- duration
- intensity
- temporal relationship to onset symptoms
- do symptoms improve when away from the workplace
what is pneumoconioses?
- uncomplicated CWP: mild disease
- progressive massive fibrosis: activation of alveolar macrophages, progressive scarring causing stiff lungs
what happens with fibrotic lung disease?
- activation of macrophages
- restrictive lung function deficit
- eggshell calcification of lymph nodes
- risk factor for TB and lung cancer
how do you treat pneumoconioses?
- prevent further exposure
- stop smoking
- monitor lung function
- symptomatic treatment: cough, dyspnoea
- no specific treatment or cure of disease itself
what benign issues does asbestos cause?
- pleural plaques
- benign pleural effusion
- pleural thickening
- asbestosis: interstitial lung disease-restrictive lung function with reduction in forced vital capacity and reduced gas transfer
what malignant issues does asbestos cause?
- lung cancer
- mesothelioma: malignancy of pleura and peritoneum caused by asbestos, consider patient history: pleural plaques on chest x-ray, persistent unexplained chest pain, weight loss, breathless/unilateral pleural effusion
what are the 2 distinct scenarios of occupational asthma (OA)?
1) occupational asthma caused by workplace exposures
2) work aggravated asthma in which pre-existing causes are made worse by factors in the workplace
what are the personal factors that need to be taken into account when diagnosis of occupational asthma (OA)?
- is it really asthma?
- consider OA in all patients presenting with asthma in adult life
- failure to respond to asthma Rx
- other risks factors: atopy, rhinitis, smoking
what are the workplace factors that need to be taken into account when diagnosis of occupational asthma (OA)?
- recognition of high risk job
- co-workers similarly affected
- recent changed: products, tasks undertaken
- preventative measures: ventilation, masks
what are the other factors that need to be taken into account when diagnosis of occupational asthma (OA)?
- have they lost their job already?
- are they seeking compensation?
- establishing a casual link can be hard
what is the role of challenge testing?
- confirm diagnosis when new agent blamed
- identify responsible agent when multiple sensisters in workplace
- confirm diagnosis when history and PEFR records are equivocal
- rarely to exclude diagnosis in patient who will otherwise lose their job
what are the criteria to fit for challenge testing & what happens?
- asthma should be stable
- withhold bronchodilators
- a placebo exposure day is advisable
- equipment that delivers known concentration of suspected agent
- monitor spirometry for several hours after each increase in exposure day
- may take several days
what is irritant-induced/non-allergic asthma?
direct effect on airways, not immune mediated occurs without pre-existing asthma
what is acute irritant-induced/non-allergic asthma?
reactive airways dysfunction syndrome (RADS): develops within hours of a single, very high exposure
what is subacute irritant-induced/non-allergic asthma?
insidious onset of asthma symptoms after multiple moderate/high empire incidents
