Unexpected allergic reactions to food:
first results of a prospective study in adults
Michelsen A1, Os-Medendorp H. van1, Versluis A1, Kruizinga A2, Castenmiller J3, Noteborn, H3, Houben G2, Knulst A1
1Department of Dermatology/Allergology, UMC Utrecht, 2Netherlands Organisation for Applied Scientific Research, Zeist,
3Netherlands Food and Consumer Product Safety Authority, Utrecht, The Netherlands
Contact: [email protected]
Introduction
Aim of this study: to investigate the frequency,
severity and causes of unexpected allergic
reactions to food in adults diagnosed with food
allergy.
Method
A prospective cohort study. A total of 250 patients
with a physician-confirmed diagnosis of food allergy
will be included and followed during one year.
Participants completed an online questionnaire after
every accidental reaction and sent in the
product with the food label they reacted on. The
product was analyzed to detect if the suspected
allergens were present.
Handling of food labels on prepackaged product
(n=20)
n
Read label
10
-
5
1
2
2
No allergens declared
Allergen not notified
Participant ignored warning
Other reason
Did not read label
8
-
2
3
1
2
Used product before without having complaints
Assumed the product did not contain allergens
Inattention
Other reason
Prepackaged product without label
2
Consuming composite meals outdoors (n = 12)
n
Cook informed or not
-
5
Preliminary results
-
Yes, the participant called
No, participant thought the product/meal
contained no allergens
No, participant ate the product/meal before
without having complaints
No, person preparing the food was not available
to inform
Other reason
Study participants n=65
Product/meal sent in for analysis (n=17 out of 45
reported reactions)
n
-
Gender
-Female
Age
-Mean age (SD, min-max) at
enrolment, in years
Most severe food allergy for:
-Peanut
-Tree nut
-Milk
-Egg
n (%)
48 (74)
38 (13,2, 19-70)
28 (43)
28 (43)
5 (8)
4 (6)
-Not confirmed
-Peanut in prepackaged product
-Peanut in composite meal
-Peanut in fresh product
-Peanut and hazelnut in prepackaged product
-Peanut and egg in fresh product
2
2
1
2
11
1
2
1
1
1
Conclusion
Figure 11
Figure
Forty-five unexpected allergic reactions were
reported in sixty-five patients. Preliminary results
showed that most reactions were on prepackaged
products and composite meals outdoors. Labelling
issues were frequently involved, as well as risk
taking behaviour. In 6 out of 17 products the culprit
allergen was identified.