Component-resolved diagnosis (CRD) is a new developement for the management of allergy that may provide an opportunity for a better identification of potential allergenic components included in an antigen. The advantages of this new analysis comprises both the measurement of specific IgE against single allergen molecules with better defined clinical prognostic value, and a microarray assay format allowing the measurement of IgE against 43 allergen molecules from the 16 most important allergenic foods.
The potential utility of this highly sensitive new technique to eosinophilic esophagitis has been described in a recent research publised in the The Journal of Allergy and Clinical Immunology. A multidisciplinary rearch team including gastroenterologists and allergists based on Amsterdam (The Netherlands) aimed to evaluate the efficacy of microarray guided-food elimination for inducing disease remission (this is, desapearance of the eosinophilic infiltration from the esophageal tissue and derived symptoms) in a group of adults with EoE.
The researchers prospectively investigated the effect of this diet in 36 patients with active disease (defined by the presence of an infilammation for >15 eos/hpf in esophageal biopsies). EoE patients underwent to blood analysis to obtain serum samples for CRD using ImmunoCAP ISAC testing. Patients with (cross-) sensitization against 1 or more food allergen identified by the CRO device were then approached for CRD-guided dietary treatment.
After baseline endoscopy, study subjects eliminated those foods that provided a positive result in CRD analyses for a period of 6 weeks. The effect was then evaluated by endoscopy with structured biopsies at distal, mid, and proximal esophagus, new blood analysis, and questionnaires.
Responders to the diet (these were the patients with <10 eos/hpf in the new biopsies) were planned to reintroduce all the avoided foods to confirm the observed effect of the diet.
Ninety-five patients were tested using CRD, of which 44 (46%) were sensitized to 1 or more food allergen according to analyses results. After inclusion of the first 15 patients, the analysis revealed that 14 patients (93%) failed the CRD-guided diet, this is, the disease remained active in all cases but in one single patient.
Because it would become impossible to meet similar efficacy as an empirical six-food elimination diet (72% of response, according the the most strong study on this topic) the resarch was prematurely terminated in consultation with the Medical Ethical Committee.
The disapointing results of this paper should promote the search of new and more convinient estrategies to guide food elimination in the treatment of EoE.