Teologia

Clinical & Experimental Allergy, 42, 568–577

doi: 10.1111/j.1365-2222.2011.03954.x

ORIGINAL ARTICLE

Epidemiology of Allergic Disease

© 2011 Blackwell Publishing Ltd

Anaphylaxis and reactions to foods in children – a population-based case
study of emergency department visits
¨
´
M. Vetander1,2, D. Helander3,4, C. Flodstrom1, E. Ostblom1,2, T. Alfven1,5, D. H. Ly2, G. Hedlin3,4,G. Lilja1,2, C. Nilsson1,2
¨
1,6
and M. Wickman
1

Department of Paediatrics, Sachs’ Children’s Hospital, Södersjukhuset, Stockholm, Sweden, 2Department of Clinical Science and Education, Karolinska

Institutet, Södersjukhuset, Stockholm, Sweden, 3Astrid Lindgren Children’s Hospital, Karolinska University Hospital, Stockholm, Sweden, 4Department of
Women’s and Children’s Health,Karolinska Institutet, Stockholm, Sweden, 5Divison of Global Health/IHCAR, Karolinska Institutet, Stockholm, Sweden
and 6Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden

Clinical &
Experimental
Allergy

Correspondence:
Mirja Vetander, Sachs’ Children’s
Hospital, So
¨dersjukhuset,
Sjukhusbacken 10, SE 118 83
Stockholm, Sweden.
E-mail: mirja.vetander@ki.se
Citethis as: M. Vetander, D. Helander,
´
C. Flodstro E. Ostblom, T. Alfven,
¨m, ¨
D. H. Ly, G. Hedlin, G. Lilja, C. Nilsson
and M. Wickman, Clinical &
Experimental Allergy, 2012 (42)
568–577.

Summary
Background Information about acute reactions to foods among children is limited.
Objective To describe the overall incidence of anaphylaxis in a paediatric emergency
department (ED) setting andto describe reactions to foods in relation to sex and age, clinical characteristics and management.
Methods In a review of medical records, children with ED visits at any of three paediatric
hospitals in Stockholm County during 2007 were targeted. Inclusion criteria were any
adverse reaction to foods or anaphylaxis.
Results 383 children fulfilled the inclusion criteria of which 371 had hadreactions to
foods. The incidence of anaphylaxis was 32 per 100 000 person years irrespective of
cause and food was involved in 92%. Tree nuts, particular cashew, and peanut were the
most common eliciting foods, and in children under 3 years, reactions to these two food
allergens were as common as reactions to milk and egg. Pollen-allergic children seemed
to be admitted due to food-inducedanaphylaxis more often during the deciduous tree
pollen season compared with the rest of the year (P = 0.015). Symptoms from the lower
airways occurred in 49% of children with anaphylaxis but without underlying asthma
compared with 72% of children with anaphylaxis and asthma, P < 0.01.
Conclusions and Clinical Relevance Reactions to peanut and tree nuts are as common as
reactions to milk and egg inearly life. Concomitant exposure to airborne allergens seems
to increase the risk of anaphylaxis to foods. Among children with anaphylaxis, wheeze is
prevalent even in children without asthma diagnosis.
Keywords anaphylaxis, children, emergency department, food allergy
Submitted 21 August 2011; revised 21 December 2011; accepted 22 December 2011

Introduction
An increase in the incidenceof anaphylaxis has been
suggested in several papers and in a recent review [1–
4]. Food has been considered the dominating cause of
anaphylaxis, in particular among children [5–11], and
represents a major health issue since anaphylaxis
caused by food may contribute towards mortality particularly among patients with asthma [12].
The true incidence of anaphylaxis among children on
a populationbasis has not yet been established [11].
This may partly be explained by the lack of universal
agreement on the definition and criteria for diagnosis

of anaphylaxis. At the time of this study, the suggested
definition encompassed a serious allergic reaction with
rapid onset and at worst with life-threatening severity
[13]. To date, few studies have primarily investigated
acute allergic...