[Immunotherapy with an oral Alternaria extract in childhood asthma. Clinical safety and efficacy and effects on in vivo and in vitro parameters].

Studies of immunotherapy with oral Alternaria extracts are scarce. We decided to perform a clinical trial of the clinical safety and efficacy of this extract as well as of its effects on in vivo and in vitro parameters in 39 patients with Alternaria allergy, aged between 7 and 17 years, who are also sensitized extract was used. Allergic activity was determined through RAST inhibition and skin prick test. Quantification of the principal allerten (Alt a 1) was performed through the 2-site binding assay, with a mean content of 34.2 ng Alt a 1/micro g protein. The parameters analyzed were the symptom-medication score, skin prick using the end-point technique, specific bronchial challenge test, peak flow, total and specific IgE and IgG4. Nineteen patiens received active treatment with oral immunotherapy and another 19 received symptomatic treatment. The initial phase of immunotherapy lasted 3 months until the maximum dose was reached. This was maintained for 12 months; the mean accumulated dos was 280,000 PNU. Significant differences were found in reduction in the symptom-medication score in the treated group after 12 months of immunotherapy. No differences were found in the control group. Immunotherapy was well tolerated with 0.42 adverse reactions per 100 doses administered. All adverse reactions were mild-to-moderate. In the treated group, papule size was significantly reduced. Values for the specific bronchial challenge test, expressed through PD20, were significantly higher in the immunotherapy group. Peak flow showed no changes in either group. Values of IgG4 were significantly higher in the immunotherapy group. Total and specific IgE levels showed no significant changes in either group. In conclusion, oral immunotherapy with Alternaria extract is clinically effective in pediatric patients. In general, the therapy was well tolerated. It modified specific cutaneous and bronchial reactivity in our sample and increased levels of specific IgG4, wich are implicated in humoral response.