Concomitant sensitisation to peanut and birch pollen is reported to be frequently seen by allergy specialists and immunologists. US researchers have utilised data for over 1900 children collected in the BAMSE birth cohort to investigate symptoms of allergic sensitisation to peanut and birch pollen.

Levels of IgE antibodies to peanut and birch pollen were measured in the subjects at 4 and 8 years, with background factors and clinical parameters also recorded for each child. IgE antibodies to peanut were found in over 5% of the children at age 4 years, and approximately 7% of children aged 8 years. Across both age groups, levels of peanut IgE antibody were higher in children sensitised to peanut but not birch pollen than in those children sensitised to both peanut and birch pollen.

Eight-year-olds sensitised to peanut but not birch pollen more often reported reactions to peanut than children sensitised to both peanut and birch pollen (76% vs 46%). The authors believe this interesting finding is due to cross reactions between birch pollen and peanut caused by structural similarities of the allergenic proteins, which in turn helps to explain the high sensitisation rate to peanut in areas where birch trees are common.

Reference: Asarnoj, et al. 2010. Allergy, Vol 65(2) pp. 213-219. Doi: 10.1111/j.1398-9995.2009.02138.x