User Questions
These are questions that users of this website want evidence based answers for. Users can associate references with these questions and leave comments.
They will be considered at the next review of the BOHRF occupational asthma guidelines in 2007.
This is not a part of the BOHRF occupational asthma guidelines.
What resources are needed in referral centres for workers with suspected occupational asthma?
| burgeps |
Barber 2007 |
not really on topic, but a paper showing how little investigation is considered in a patient with possible occupational asthma seen by general consultant respiratory physicians in the UK |
How big a difference between mean PEF on workdays and restdays is required to diagnose occupational asthma
Can occupational asthma exist with a diurnal variation in PEF consistently below 15%
What is the benefit of substitution of a sensitising agent in the control of occupational asthma
| burgeps |
Linnett 1999 |
A good example of controlling sensitisation by substituting ammonium hexachlorplatinate with tetraammine platinum dichloride in catalytic car exhaust manufacture |
What is the effect of omalizumab on occupational asthma?
What is the role of exhaled breath Nitric Oxide in the diagnosis and management of occupational asthma.
| Cedd Burge |
Smit 2009 |
Gives a good estimate of the effect of current smoking on the reduction of exhaled breath nitric oxide, which also appears lower in females than in men. |
| burgeps |
Baur 2005 |
eNO measured at 1 and 22 hours following specific challenge with powdered latex gloves and powdered vinyl gloves as control. eNO increased at 1 hour in challenge positive and negative workers (39% challenge positive and 71% challenge negative). At 22 hours an increase >50 in eno had a sensitivity of 69% for astma and 35% for rhinitis. Specificity (no rhinitis or asthma) 100%. eNO reduced in smokers, sensitivity >50% at 22 hrs smoking asthmatics 50% and non-smokers 100%. Supports eNO at 22 hours only in latex asthma, does not separate occupational asthma from occupational rhinitis, but increase >50 at 22 hours seems specific |
| burgeps |
Lemiere 2010 |
The effects of inhaled corticosteroids on FeNO levels appeared to be gone 72 hours after the last dose. There was no increase 7 hours post challenge, an increase >10ppb seen in 6/16 challenge positive workers at 24 hours. FeNO did not contribute to the interpretation of the challenge in this post hoc analysis |
What is the use of induced sputum eosinophilia in the diagnosis of occupational asthma
| burgeps |
Vandenplas 2009 |
6 of 35 workers with an initial negative specific challenge had a positive challenge on a separate day with higher exposures. 4/6 had an increase in sputum eosinophils >3% after the first negative challenge. 2/29 without occupational asthma also had a >3% increase in sputum eosinophilia after a negative challenge. In this retrospective analysis an increase in sputum eosinophils >3% had a sensitivity of 67% and specificity 97%. Most were exposed to HMW agents. (the paper quotes specificity of 97% but table 2 suggests 2 controls had an increase of at least 3%). NSBR not so sensitive |
| burgeps |
Moscato 2010 |
occupational asthma present with and without sputum eosinophlia. Eosinophilia present in occupational rhinitis |
| burgeps |
Lemiere 2010 |
A 2.2% increase in sputum eosinohils post challenge was seen in 16/20 challenge positive workers and 3/16 challenge negatives. Not affected by maintenance inhaled corticosteroids. This was a post hoc analysis |