Significantly reduced risk of anaphylactic shock for children with severe allergies. It is the effect of a drug to improve the control of allergic asthma, which has proved capable of raising a protective barrier even against anaphylaxis, the form more severe than food allergy.
The discovery was made by allergist researchers at the Bambino Gesù Pediatric Hospital who observed reactions to various food allergens in a group of children during treatment with the drug omalizumab. The results of the study have just been published in the scientific journal Journal of Allergy and Clinical Immunology: in practice.
FOOD ALLERGY: 5 CHILDREN OVER 100
Allergic diseases are the most common chronic diseases in the population after arthritis and arterial hypertension. Food allergies in particular, affects 5 out of 100 children, with a peak in the first 3 years of life. This form of allergy is triggered by the proteins contained in certain foods that – due to an immune system error – are recognised as threats, triggering the inflammatory reaction. In about 40% of cases food allergy is associated with severe allergic asthma that affects lung growth and reduces quality of life.
Anaphylaxis is the most severe form of food allergy. In pediatric age it has a prevalence of between 1 and 3% of cases of food allergy and is 10 times more frequent among children than among adults.
The symptoms of allergic reaction to food develop very quickly. It is enough to ingest, make contact, or simply inhale minute quantities of “incriminated” food to immediately create urticaria, swelling and edema of the face, itching and swelling of the extremities, rhinitis, conjunctivitis, shortness of breath, and a convulsive cough. Just as quickly, in about 3 cases out of 100, the symptoms of an allergic food manifestation progress up to the reduction of blood pressure and anaphylactic shock. Children with a food allergy associated with severe allergic asthma are at greater risk of experiencing anaphylactic shock.
THE STUDY AND EFFECTS OF THE OMALIZUMAB DRUG
The Bambino Gesù researchers, led by Prof. Alessandro Fiocchi, have studied a group of 15 children and teenagers, aged between 6 and 18, suffering from severe allergic asthma associated to complex forms of food allergy (immediate reaction to 2 or more foods).
The study lasted almost 3 years. During this period, reactions to various food allergens were observed before and after the start of treatment with omalizumab, an active ingredient used to treat persistent severe allergic asthma. The drug acts directly against immunoglobulins E (IgE), which are at the origin of asthmatic crises, preventing inflammatory attack. Of documented efficacy on the front of allergic asthma and chronic urticaria, to date the effects of omalizumab on other forms of allergy have been poorly investigated. The study has shown its positive effects also on severe food allergies, i.e. on the level of tolerability of food allergens during treatment for severe asthma.
RESULTS OF THE STUDY
The 15 patients enrolled in the research showed immediate allergic reactions to 37 foods. 80% of them had already faced episodes of anaphylaxis. The researchers tested the levels of reactivity for 23 different foods (including milk, eggs, wheat, hazelnut) before and after the start of treatment with omalizumab. The comparison of the data showed an increase in the tolerance threshold to allergens (we went from an initial average threshold of 460 mg of protein to 8192 mg) which significantly reduced the risk of anaphylactic shock in case of involuntary contact with “prohibited” food. In fact, during the observation period, the number of reactions to accidental allergen ingestion fell from 47 to 2 episodes recorded.
Thanks to the protective action of the drug, over 70% of tested foods (15 out of 23) have been safely reintroduced into the children’s diet, without the need for oral immunotherapy procedures. The remaining foods were almost completely tolerated. According to the opinion of parents and patients, expressed through a questionnaire, the quality of life increased on average by 40% .
“The study has allowed us to understand that with omalizumab food allergies cease to be dangerous and that doses of food which before were very risky can be tolerated, almost eliminating the risk of anaphylactic shock”, explains Alessandro Fiocchi.
“With the administration of the drug the child gains a state of tolerance that allows him to breathe, eat and get in touch with allergens, even the most dangerous for him, without having damage. The results of our research now open the way to prospective studies on the appropriateness of using the treatment also for selected cases of patients with food allergy who do not have asthma.”