ORIGINAL ARTICLE Oral desensitization as a useful treatment in 2-year-old children with cow’s milk allergy A. Martorell 1à , B. De la Hoz 2à , M. D. Ib´ a˜ nez 3 , J. Bone 4 , M. S. Terrados 2 , A. Michavila 5 , A. M. Plaza 6 , E. Alonso 7 , J. Garde 8 , S. Nevot 9 , L. Echeverria 10 , C. Santana 11 , J. C. Cerd ´ a 1 , C. Escudero 3 , I. Guallar 4 , M. Piquer 6 , L. Zapatero 7 , L. Ferr´ e 9 , T. Bracamonte 10 , A. Muriel 12 , M. I. Mart´ ınez 13 and R. F´ elix 1 1 Hospital General Universitario, Unidad de Alergolog´ ıa, Valencia, Spain, 2 Hospital Ram ´ on y Cajal, S. Alergolog´ ıa Infantil, Madrid, Spain, 3 Hospital Universitario Ni ˜ no Jesu ´s, S Alergolog´ ıa Infantil, Madrid, Spain, 4 Hospital Miguel Servet, S. Alergolog´ ıa Infantil, Zaragoza, Spain, 5 Hospital General, S. Alergolog´ ıa Infantil, Castell ´ on, Spain, 6 Hospital San Joan de D ´ eu, S. Alergolog´ ıa Infantil, Barcelona, Spain, 7 Hospital Gregorio Mara ˜ n´ on, S. Alergolog´ ıa Infantil, Madrid, Spain, 8 Hospital General Universitario, Unidad de Alergolog´ ıa, Elche, Spain, 9 Hospital Sant Joan de Deu, S. Alergolog´ ıa Infantil, Manresa, Spain, 10 Hospital Severo Ochoa, S. Alergolog´ ıa Infantil, Legan ´ es, Spain, 11 Hospital General, S. Alergolog´ ıa Infantil. Segovia, Spain, 12 Unidad Bioestad´ ıstica Hospital Ram ´ on y Cajal, Madrid, Spain and 13 Fundaci ´ on Hospital General Universitario, Valencia, Spain Clinical & Experimental Allergy Correspondence: Antonio Martorell Aragon´ es, Hospital General Universitario, Unidad de Alergolog´ ıa, Avenida Tres Cruces 2, 46014 Valencia, Spain. E-mail: martorell_ant@gva.es Summary Background Limited published evidence shows oral desensitization to be a potential intervention option for cow’s milk protein (CMPs) allergy. Objective The aim of this study was to evaluate the safety and efficacy of oral desensitization in 2-year-old children with cow’s milk allergy, as a treatment alternative to elimination diet. Methods A total of 60 children aged 24–36 months with IgE-mediated allergy to CMPs were included in this multi-center study and were randomized into two groups. Thirty children (group A: treatment group) began oral desensitization immediately, whereas the remaining 30 (group B: control group) were kept on a milk-free diet and followed-up for 1 year. Results After 1-year follow-up period, 90% of the children in group A had become completely tolerant vs. 23% of the children in group B. In group A, cow’s milk skin reactivity and serum- specific IgE to milk and casein decreased significantly from the initial assessment, whereas group B showed no significant change after 1 year of follow-up. Twenty-four patients (80%) developed some reaction during the treatment period: 14 children developed moderate reaction (47%) and 10 mild reaction (33%). The most common manifestations were urticaria- angioedema, followed by cough. Conclusions and Clinical Relevance In this study, oral desensitization was found to be effective in a significant percentage of 2-year-old children with cow’s milk allergy. Oral desensitization appears to be efficacious as an alternative to elimination diet in the treatment of 2-year-old children with cow’s milk allergy. The side-effect profile appears acceptable but requires further study. Keywords cow’s milk allergy, food allergy, oral desensitization, randomized trial, specific oral tolerance induction Submitted 19 September 2010; revised 22 February 2011; accepted 24 February 2011. Introduction Allergy to cow’s milk proteins (CMPs) is the first food allergy to manifest in children [1, 2]. The current options for the management of food allergy are based on allergen avoidance, until the development of tolerance. However, in some very common foods such as cow’s milk, this approach is difficult to apply. Moreover, not all subjects reach tolerance. In some cases the problem persists for years, and the longer symptomatic sensitization persists, the smaller the chances for resolution of the disorder [3–6]. The difficulty of strict avoidance of the causal food, and particularly the risk of reaction, have led to research into à Contributed equally and first authors. Clinical & Experimental Allergy, 1–8 doi: 10.1111/j.1365-2222.2011.03749.x  c 2011 Blackwell Publishing Ltd