Role of immunological mediators in the follow-up of asthma and allergic rhinitis patients on allergen immunotherapy

BACKGROUND: Bronchial asthma (BA) is characterized by chronic airway inflammation. Many studies have shown a significant overlap between BA and allergic rhinitis (AR). Specific allergen immunotherapy (AIT) is effective for the treatment of BA and AR. Only limited studies have evaluated the role of immunological parameters to assess the response in patients on AIT. Hence, this study was done to assess the role of interleukin-4 (IL-4), IL-5, and IL-6 in the follow-up of patients of BA and AR on AIT. MATERIALS AND METHODS: This study was conducted on diagnosed cases of BA, AR, and BA with AR attending the outpatient department who were started on subcutaneous immunotherapy as per the standard Indian guidelines. Blood samples were collected at the beginning of the treatment and every 3 months thereafter for a period of 51 months, and serum IL-4, IL-5, and IL-6 levels were measured. RESULTS: In this study, 170 patients were enrolled over a period of 51 months. Out of 170, 80 (47.1%) patients had completed 1 year of treatment with AIT at the end of 51 months of follow-up. Significant reduction was observed in IL-4, IL-5, and IL-6 levels during the treatment with AIT over a period of 12 months. CONCLUSION: Our study suggests a possible role of IL-4, IL-5, and IL-6 in the follow-up of BA and AR patients; however, further studies are needed in this area.