Comments on ‘Anti-Ige Therapy for Eosinophilic Disorders’

Abstract

To the Editor We read the article entitled, “Clinical efficacy of anti-IgE therapy for eosinophilic otitis media,” in your journal Otology & Neurotology (1). In the article, although a limited number of cases were presented, the results seem to be very valuable and promising. However, the effectiveness of omalizumab on the immune system and on eosinophils has not been discussed in detail by the authors. The efficacy of omalizumab was also presented in many case reports, including varying disorders in which eosinophils play a prominent role in etiology (2,3). In addition, the effectiveness of anti-IgE treatment has been shown in many disorders with complex and unclear etiology, including physical urticarias (cold urticaria, solar urticaria, symptomatic dermographism, delayed pressure urticaria, and cholinergic urticaria), chronic idiopathic urticaria, and angioedema (4–7). We would like to share our experience on 5 patients who had physical urticaria associated with persistent moderate to severe allergic asthma that could not be controlled with antihistamines but benefitted dramatically from anti-IgE treatment of both physical urticaria and asthma. The quality of life of all patients was improved shortly after the first dose, as measured using the Dermatology Life Quality Index (8). It seems that the beneficial effectiveness of anti-IgE treatment in both allergic asthma and physical urticaria, as seen in our cases, may either indicate that IgE has a central role in the pathogenesis of these disorders or reflect the complexity of anti-IgE treatment. One of the most striking studies reflecting the complex effectiveness of anti-IgE treatment on the immune system is reported by Sayama et al. (9). They reported that stimulation of Fc[Latin Small Letter Open E]RI in human umbilical cord mast cells causes a substantial change in the expression of many genes, including 18 cytokines, 13 chemokines, and several adhesion molecules involved in potential interactions with T cells, B cells, or dendritic cells. Omalizumab downregulates the expression of IgE receptors (Fc[Latin Small Letter Open E]RI) on mast cells and basophils. The downregulation of Fc[Latin Small Letter Open E]RI expression is associated with a loss of sensitivity to allergen challenge and a reduction in mediator release, which has a potential effect on reducing circulating and tissue eosinophils (10). In conclusion, it seems that the therapeutic effectiveness spectrum of anti-IgE treatment will comprise many allergic disorders with unknown etiology, including eosinophilic otitis media. Murat Salihoglu Department of Otolaryngology GATA Haydarpasa Training Hospital Istanbul, Turkey [email protected] Ercan Karabacak Department of Dermatology GATA Haydarpasa Training Hospital Istanbul, Turkey Ali Kutlu Department of Allergy and Immunology GATA Haydarpasa Training Hospital Istanbul, Turkey Aptullah Haholu Department of Pathology GATA Haydarpasa Training Hospital Istanbul, Turkey