[Frequency of Food-Sensitization by Prick-to-Prick Skin Tests and Atopy Patch Tests in Children with Allergic Diseases]. / Frecuencia de sensibilización a alimentos por pruebas cut·neas de prick-to-prick y de parche en niños con enfermedades alérgicas.

BACKGROUND: Food allergy is a health problem that has increased its prevalence in the last decade, and plays a role in the multiple symptoms of allergic diseases like asthma, atopic dermatitis and allergic rhinitis. It has become the new epidemic with significant implications. OBJETIVE: To describe the frequency of sensitization to food antigens by skin tests, prick-to-prick and atopy patch tests, in a group of allergic children in a pediatric hospital. METHODS: We retrospectively reviewed the results of skin tests with foods, prick-to-prick and atopy patch tests, in the clinical records of 170 and 140 children respectively, with a diagnosis of asthma, allergic rhinitis, atopic dermatitis, food allergy or eosinophilic gastroenteropathies, and analyzed the results with measures of central tendency and chi2 test. RESULTS: Immediate hypersensitivity tests with fresh foods (prick-to-prick) were positive in 135 cases. Cowís milk was positive in 28.8%, followed by egg white with 20.1% and banana in 19.4%. In the group of 1 to 5 years, cowís milk was positive in 26.9% (p <0.05). In children with a previous diagnosis of food allergy cowís milk was positive in 27.1% (p<0.05). In delayed hypersensitivity tests (patch tests) there were 105 positive results; soybean was positive in 53.3% of cases tested, followed by peanut and chocolate with 50.5%. In the group with atopic dermatitis soybean was positive in 55.6% (p <0.05). In the group of 1 to 5 years, soybean was positive in 52.1% (p <0.05). CONCLUSIONS: In children with various allergic diseases, with prick-to-prick skin tests, cowís milk was the food allergen with more frequent positive results. When we used atopy patch tests, soybean was the food with more positive results. We observe sensitization to different foods, according to the mechanism of injury, type I or IV, which is dependent on the type of skin tests used.

[Desensitization protocol to methotrexate. Clinical case]. / Protocolo de desensibilización a metotrexato. Caso clinico

Methotrexate (MTX) is a folic acid antagonist; its main effects are immunosuppressive and antineoplastic. It is used in the treatment of malignancies, lung and rheumatic diseases. There are few reports of immediate hypersensitivity and these include anaphylaxis, urticaria and angioedema. We present a 17 years old male, with a history of anaphylaxis to methotrexate during the induction therapy of ALL L2. It was decided that the drug was necessary for the patientís survival, thus diagnostic skin testing was performed, during which he presented anaphylaxis. The desensitization consisted of 5 days premedication and a 12-steps protocol of intravenous infusions of 8 hoursí duration, starting with a 1:1.000.000 dilution. The patient was successfully desensitized. He was maintained with IV MTX 50mg/m2 weekly for 1 year using the same protocol successfully. This protocol of 12 steps was successful and safe to desensitize a patient with anaphylaxis due to MTX. During such protocol intensive care supervision is critical, as all precautions should be taken to avoid endangering the life of the patient.