Background: Allergic rhinitis represents a global health problem that causes major illness and disability worldwide. Immunotherapy is effective in the management of allergic rhinitis. Skin prick test is a reliable method to diagnose IgE-mediated allergic disease. Up-to-date, no biomarker has yet been validated to be a good predictor of clinical response to allergen immunotherapy.
Method: This is a cohort study to determine the association of skin prick test result to allergen immunotherapy efficacy in children with allergic rhinitis. Patients seen at a tertiary hospital diagnosed with allergic rhinitis and on allergen immunotherapy were included in the study. Skin prick test results were recorded and total nasal symptom score (TNSS) were obtained at the start of immunotherapy and monthly for six months. The correlation of the baseline skin prick test to the change in TNSS for each monthly endpoint was done to check for the association between the baseline skin prick test and the efficacy of immunotherapy measured as the improvement in TNSS scores.
Results: A total of 18 patients who have completed at least six months of immunotherapy were included in this study. Average age is 13.22 + 3.62 years old, and were predominantly male (11 out of 18, 61.1%). The average skin prick test to D.farinae was 7.72 ± 3.80 mm, while that of D.pteronyssinus was 8.56 ± 4.34 mm. At baseline, the TNSS of the subjects had a median score of 7.5 which gradually decreased to a median score of 3 by the sixth month of immunotherapy. There was generally low and inverse correlation between D.pteronyssinus immunotherapy and skin prick test results for the first four months of immunotherapy, after which, there was a direct and moderate correlation from the fourth to sixth month of immunotherapy (p=0.3128), however it was not statistically significant. There was a low and inverse correlation between D.farinae immunotherapy and skin prick test results for the first four months of immunotherapy, after which, there was a direct but low correlation from the fifth to sixth month of immunotherapy (p=0.2550).
Conclusion: The larger the size of the skin prick test to D.pteronyssinus, the greater the improvement of the total nasal symptom score from the baseline at six months of immunotherapy.