Asthma caused by oilseed


Occupations
  • Animal breeder
  • Docker
  • Oil-works employee
  • Perfumer
Agents
Ambrette, Castor oil (Ricin), Flax, Hibiscus abelmoschus, Oilcake, Peanut, Rapeseed oil (Colza).
 
Incidence
Incidence: between 3 and 5% of exposed subjects.
 
Atopic subjects seem to be predisposed towards the disease, however some non-atopic subjects are also affected.
 
IgE-dependent mechanism.
 
The allergen is a low molecular weight protein.
 
Conditions
Contamination of work place and surrounding areas during processing. When castor oil cakes are used as "natural" fertilisers, a number of different professions may be affected including deliverymen, retailers, wholesalers etc.
 
The volatile organic components of rapeseed can be irritative and/or allergenic. These rapeseed oilcake/cattle-cakes are used in the feeding of livestock. Cases of occupational asthma have recently been reported in animal breeders, demonstrating that moderate exposure, and even occasional exposure can give rise to true sensitisations.
 
Symptoms
Violent asthmatic attacks, epidemic, symptoms cease after contact with the causative agent. Attacks may be immediate or delayed. In the case of asthma caused by ambrette (Hibiscus Abel.) working with oilseed and powdered seeds also causes eczema.
 
Diagnostic methods
Skin prick test: 1/100 dilution for castor oil (not commercially available).
 
Immunological assay: RAST/CAP RAST castor oil, peanut and rape seed.
 
IDR tests may induce lymphangitis.
 
Bronchial provocation tests (in hospital) must be preceded and followed by a measure of bronchial hyperreactivity. The threshold for bronchial hyperreactivity is lowered following the bronchial provocation test. Eosinophil numbers are increased in induced sputum in cases of asthma induced by these allergens.

References

  1. Allergy 2001,56:185 Alvarez MP.J. et al.
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  3. Allergy 1994,49:897
  4. Rev. Fr. All. 1990,30,29:31
  5. Int. Arch. Appl. Immun. 1987,82:456
  6. Int. Arch. Appl. Immun. 1981,64:230
  7. Allergy 1983,38:155
  8. Clin. Allergy 1983,13:553
  9. Clin. Allergy 1981,11:463
  10. J. Allergy Clin. Immunol. 1990,85:778
  11. Lancet 1989,1:179
  12. Acta Allergol. 1959,14:150

As in all diagnostic testing, the diagnosis is made by the physican based on both test results and the patient history.