Food allergies represent an increasing health concern in the industrialized countries and especially affect pediatric patients. In this population adverse reactions against food compounds can lead to anaphylactic reactions. Despite substantial research efforts, clinical markers predicting disease severity and symptoms are missing to date.

Recent studies have revealed that sphingolipids, especially sphingosine-1-phosphate (S1P), play an essential role in allergy. It was reported that asthmatic patients have higher S1P levels in bronchiallavage fluids after allergen challenge. First experimental studies revealed a correlation of S1P and the outcome of anaphylaxis. Furthermore, we have shown in our recent mouse study that S1P homeostasis is pivotal for food allergy induction and effector cell response. Therefore, it is the aim of the presented pilot project to evaluate whether S1P serum titers are altered in food allergic children and if the S1P levels correlate with the outcome of anaphylaxis during double blind placebo controlled food challenges (DBPCFCs).

Inclusion Criteria:

• Patients between 1-17 years who have been reported to suffer from food allergic reactions and who are subjected to DBPCFC or open provocation
• Patients who are diagnosed by elevated allergen specific IgE and/or positive skin prick testing
• Willingness to participate in the study

Exclusion Criteria:

• Refusal to participate in the study
• Non-IgE-mediated food allergy

Children (age 1-17 years) being in medical care at the allergy clinic of the Department of Pediatrics and Adolescent Medicine of the Medical University of Vienna for food related immediate type symptoms (nausea, abdominal pain, vomiting, diarrhea or local symptoms like burning, swelling, itching and erythema) immediately after ingestion of food compounds will be enrolled in this study.