Clinical trial NCT01744990: Tree Nuts Allergies: Does a Single Nut Allergy Necessitate the Dietary Eviction of Other Tree Nuts?
Official title: Tree Nuts Allergies: Does a Single Nut Allergy Necessitate the Dietary Eviction?
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Nut Allergy in Children
Keywords: Nuts
allergy
Oral food challenge
skin testing
basophil activation tests
specific IgE's
Lead sponsor: University Hospital, Geneva
Sponsor class: OTHER
Collaborators: name: Allergistiftung Ulrich Müller
name: Food Allergy Research & Education
First posted: 2012-12-07
Enrollment: 130
Sex: ALL
Minimum age (years): 12
Maximum age (years): 16
Standard ages: CHILD
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: DIAGNOSTIC

Brief summary: The aim of this study is to identify, based on standardized food provocation tests, which nuts allergic patients need a selective, or a complete dietary eviction of all kind of nuts (nuts being defined as peanut, all tree nuts, pine nut and sesame). The investigators postulate that predictive factors of multiple nut allergy are high specific immunoglobulin E level, positive skin tests and/or clinical markers, such as atopic dermatitis, presence of other food allergies or a history of a severe previous reaction

Detailed description: Food allergy in children is a disease of growing importance, current estimation in school age children are between 4 and 8 %. The most frequently involved foods in IgE reaction in school-aged children are hazelnut (especially in Switzerland according to the ongoing Swiss Registry, Wiesner et al, personal communication) and peanut. Tree nuts and peanut allergies are often involved in severe reactions, including cases of death by anaphylaxis. In addition, the disease is long-lasting as Fleischer et al could show that only 9% of children with nut allergies will outgrew from it. This number is worse than for peanut where a positive outcome is seen in 20% of the patients.

Food challenges are the most reliable tests to investigate a possible food allergy, but these are time consuming and may elicit severe reactions in patients with a previous history of anaphylactic reactions(8). There are no allergy tests able at this time to predict with certainty the clinical reactivity, although Sampson et al could identify a general tree nuts specific IgE cut-off level with a high positive predictive value for clinical reactivity.

It could be demonstrated, in well-designed studies, that in vitro cross-sensitivity between tree nuts (members of the oleaginous family) and peanut (members of the legume family) is frequent (86%). However, clinical reactions to tree nuts are estimated to be present in only 40% of peanut allergic patients. Therefore 60% of peanut allergic patients may eat tree nuts without reactions.

Similarly, there is a large in vitro cross-sensitivity between tree nuts. However, it is not known to date if this cross-sensitivity relates to clinical reactivity. Consequently, in case of one tree nut allergy, strict eviction to all nuts is largely recommended, and possibly results in a unnecessary dietary eviction of all tree nuts leading to a high impact on the quality of life of the children.

We aim to identify, based on standardized food provocation tests, which nuts allergic patients need a selective, or a complete dietary eviction of all kind of nuts (nuts being defined as peanut, all tree nuts, pine nut and sesame). We postulate that predictive factors of multiple nut allergy are high specific immunoglobulin E level, positive skin tests and/or clinical markers, such as atopic dermatitis, presence of other food allergies or a history of a severe previous reaction.

Eligibility criteria: Inclusion Criteria:

* Children 1 - 16 years of age at the time of inclusion (a minimum of 75 children \< 6 years old required, over the 3 centers)
* Children with convincing history of IgE-mediated systemic allergic reaction (not only oral symptoms) after consumption of one or more "nuts" (peanut, hazelnut, walnut, almond, cashew, pecan, Brazil, macadamia, pine nut, sesame) within last 12 months and SPT \> 3 mm and/or positive specific IgE (\>0.1 kU/l).
* Children without a convincing history of IgE-mediated systemic allergic reaction (for example only oral symptoms) after consumption of one or more "nuts" (peanut, hazelnut, walnut, almond, cashew, pecan, brazil, macadamia, pistachio, pine nut, sesame) but with clear evidence of sensitization (SPT \> 3 mm and/or positive specific IgE (\> 0.1 kU/l) and a positive standardized food challenge to the nut.
* Informed consent approved and signed by the patient's legal representative and, if applicable, by the child itself.

Exclusion Criteria:

* Uncontrolled asthma (according to the European Guidelines)(13)
* Chronic urticaria
* Children with a chronic systemic disease
* Children who are dependent on daily antihistamine use

Primary outcomes:
measure: Evaluation of cross reactivity in nut allergic children
timeFrame: 12 months
Secondary outcomes:
measure: Identify predictive factors of multiple nut allergy
timeFrame: 12 months
measure: Quality of life in food allergic children
timeFrame: 36 months
measure: Follow up visits to evaluate the uprising of an allergy to a nut regularly ingested
timeFrame: 36 months
Other outcomes:
Locations:
city: Valencia
country: Spain
facility: Hospital Infantil La Fe
city: Geneva
country: Switzerland
facility: University Hospital Geneva
state: GE
city: Chertsey
country: United Kingdom
facility: St. Peter's Hospital
state: Surrey
city: London
country: United Kingdom
facility: St. Thomas' Hospital
Study officials:
affiliation: University Hospital, Geneva
name: Philippe A Eigenmann, MD
role: STUDY_CHAIR
affiliation: St. Thomas' Hospital, London (UK)
name: Gideon Lack, MD
role: STUDY_CHAIR
affiliation: Hospital Infantil La Fe, Valencia, Spain
name: Antonio Nieto, MD
role: STUDY_CHAIR
affiliation: St. Thomas' Hospital, London (UK)
name: Helen Brough, MD
role: PRINCIPAL_INVESTIGATOR
affiliation: St. Peter's Hospital, Surrey (UK)
name: Haddad Diab, MD
role: PRINCIPAL_INVESTIGATOR
References: