The prevalence of oilseed rape hypersensitivity in a mixed cereal farming population.

Background: Oilseed rape production is widespread in cereal growing areas. Many patients attending our clinics for seasonal allergy claim that they are allergic to it.

Aim: To determine the prevalence of oilseed rape allergy in our population.

Population: General population within a mixed cereal farming area attending a rhinology and allergy clinic in a district general hospital, UK.

Methods & Materials: Retrospective chart analysis. The results of 1475 consecutive patients who underwent skin prick allergy testing over a 2-year period (January 2003-December 2005) and of 640 consecutive patients over a 1-year period (September 2008-September 2009) were analysed and compared.

Results: Allergy to house dust mite was found to be most common (n = 526, 25%) followed by grass pollen (n = 519, 24%) and cereals (n = 429, 20%). Oilseed rape hypersensitivity was relatively uncommon, comprising only 2% of the population tested (n = 28).

Conclusion: Oilseed rape does not cause significant allergy, even in areas of high production. It is likely that those patients exhibiting oilseed rape allergy may in fact be symptomatic due to the effect of other allergens, acting either synergistically with the oilseed rape allergen, or more likely, in spite of it.