Omalizumab, a humanized monoclonal anti-IgE antibody has the potential to alter allergen processing. Recently, it has been postulated the assessment of PHA-stimulated adenosine triphosphate (ATP) activity as maker of CD4+ T cells activity in peripheral blood cells. We present the case report of a 35-year-old woman with a history of chronic idiopathic urticaria and angioedema of 8 years of development with poor response to treatment. The patient was partially controlled with cyclosporine at doses of 100 mg/12 h. However, she was still developing hives daily. Finally treatment with omalizumab was started at dose of 300 mg every 2 weeks. The patient experienced a decrease in urticarial lesions 2 days after starting therapy. We also evaluated the effects of omalizumab therapy on the activity of peripheral blood CD4+ T cells from the patient, in order to determine the potential modification of anti-IgE therapy on the process of antigen presentation-recognition. Activity of CD4+ cells by ATP release was clearly increased demonstrating an enlarged CD4 activity. Omalizumab may be useful in the treatment of severe chronic urticaria. ATP activity of peripheral blood CD4+ T cells might be a non-subjective method to assess Omalizumab activity.

The prevalence of many phenotypes of food allergy is increasing. Specific gastrointestinal (GI) phenotype of food allergy (GI allergy) is also increasing but it is difficult to know the prevalence because of many entities. A 1 year retrospective study of pediatric patients complaining exclusively gastrointestinal symptoms after cow’s milk consumption and at least one positive specific IgE (sIgE) to cow’s milk (CM) proteins (CMP) was done (n = 39). The most prevalent symptom was abdominal cramps in 35 patients (90 %), discomfort or abdominal distention in 30 patients (75 %), diarrhea in 10 patients (25 %) and constipation in 5 patients (12 %). IgA anti-transglutaminase antibodies were absent and lactose intolerance was ruled out in all patients. Average of total IgE on this group was 288 UI/ml. sIgE against β-lactoglobulin was the dominant with an average of 4.14 kU/l. sIgE to casein (CAS), which is the dominant protein in systemic anaphylaxis was 1.74 kU/l; sIgE to α-lactoalbumin, the other whey protein, was 0.83 kU/l and sIgE levels to CM were 0.78 kU/l. The quotient sIgE CAS/sIgE β-lactoglobulin in these patients was always lower than 1. Patients experienced an improvement of their symptoms after a CM free diet. An open oral challenge with CM did mimic their initial symptoms in all patients. However, the open oral challenge with dairy products was well tolerated. Patients with a specific phenotype of GI allergy with CM have specific IgE against β-lactoglobulin, as a dominant sIgE. These patients could beneficiate of a diet with dairy products.