Correlation of SPT or OFC Positive Results to IgE on a Novel Immunoassay System.

RATIONALE: The detection of serum-specific IgE (sIgE) is increasingly being used to aid in the diagnosis of an allergy sensitization. However, skin prick tests (SPT) and oral food challenges (OFC) continue to remain the gold standards for confirming allergy diagnosis. The purpose of this study is to determine the correlation between a positive SPT or OFC result and an IgE result obtained on the new system*.

METHODS: The system is a fully-automated immunoassay platform to quantify specific IgE concentrations in serum and utilizes magnetic microparticles to which allergens are coupled by a process called “on-board kitting”. The assay then adds 4 µL of serum to the coated beads in order to quantify sIgE concentrations for that allergen. For this study, remnant de-identified human samples were selected based on a positive skin prick test or oral food challenge to 8 common inhalant allergens and 3 food allergens.

RESULTS: For each allergen, 10 to 30 positive SPT or OFC samples were identified and tested on the system (level >0.35 kU/L is considered a positive result). For the 8 inhalant allergens, an average of 76% positive agreement (min: 67%, max: 87%) between SPT and the system was found. For the 3 food allergens, the average was 93% positive agreement (min: 90%, max: 100%) between OFC and the system.

CONCLUSIONS: The data demonstrates general agreement with OFC and SPT; this suggests that the new system could be an important tool in the monitoring of allergen sensitivity.

*For Investigational Use Only.