Local and Systemic Reactions Occurring During Immunotherapy: An Epidemiological Evaluation and a Prospective Safety-Monitoring Study

Abstract

The efficacy of specific immunotherapy in allergic patients with IgE-mediated rhino-conjunctivitis, asthma and allergic reaction for stinging insects suggests the opportunity of improving technical procedures to minimize risk and optimise the safety of immunotherapy. This study investigated both local and systemic reactions, occurring in a population of 218 patients undergoing immunotherapy, in an attempt to correlate them with some parameters as well as age, sex and allergenic extracts. The epidemiological evaluation was based on the administration of a questionnaire to 218 patients in order to assess possible reactions to immunotherapy. The following data were evaluated: personal data, diagnosis, specific allergens, adverse reactions undergone during treatment, number of reactions and symptoms. The patients were followed-up by the medical staff of the Section of Allergological and Immunological Disease (SAID), University of Bari (Bari-Italy) for compilation of questionnaires. We found a correlation between female sex and adverse reactions. Among 107 patients referring reactions to the immunotherapy, 71 patients (66.3%) presented only local reactions; 11 patients (10.3%) systemic reactions and 25 patients (23.4%) systemic reactions associated with local reactions. Parietaria was mostly involved in patients with local reactions, instead, in patients with systemic reactions the prevalent allergens seem to be Dermatophagoides and grass-pollen. Rhinitis was the most frequent diagnosis for patients who have presented both local and systemic reactions. In our study, we had frequently mild systemic reactions and some cases of respiratory difficulties, while it is evident that in our group of patients no cases of anaphylaxis occurred. In addition, we considered some events before the administration of immunotherapy, such as assumption of drugs, meals, exposure to sun, stress or physical activity and the percentage of adverse reactions. On the light of a small number of fatality, immunotherapy represents a safer therapy for allergic diseases; nevertheless, our data suggest that safety is strictly correlated with prescriptions by specialists, administration by trained physicians and accurate follow-up of patients. In particular it is recommended to avoid some events before the administration of immunotherapy, above all the assumption of drugs and physical exercise.