Background: Synbiotics have been used in the prevention and treatment of various immunological diseases. We aimed to investigate the synergistic clinical and immunologic effects of synbiotics and subcutaneous allergen immunotherapy (SCIT) combination in patients with allergic rhinitis.
Materials and Methods: Nineteen individuals with allergic rhinitis were enrolled in this single blind, placebo-controlled trial between 2015 and 2016 in Qaem Hospital, Mashhad, Iran. Patients were randomly divided into two groups: A) Immunotherapy plus one synbiotic capsule per day, and B) Immunotherapy plus placebo for two months. The Sino-nasal outcome test (SNOT-22), and mini rhinoconjunctivitis quality of life questionnaire (RQLQ) were filled by patients or their parents while intracellular expression of interlukin-4 (IL-4), interferon-gamma (IFN-gamma), and Forkhead Box P3 (FOXP3), and variations in the T helper 1 (Th1), T helper 2 (Th2) and T regulatory cells and cytotoxic T lymphocytes (CTL) frequency were examined by flow cytometry assay at baseline, after 2 and 6 months of intervention.
Results: Nineteen individuals with allergic rhinitis aged between 5 and 55 years participated in this study. No significant difference in the frequency of symptoms between the two groups was observed after 2 and 6 months of intervention (p>0.05). A significant increase in the percentage of Th1 cells was recorded in group A compared to group B (p= 0.02). CTL enhancement percentage was significantly increased in group A compared to group B after 2 months (p=0.013).
Conclusion: Subcutaneous Immunotherapy concomitant with synbiotics administration may have temporarily increased the percentage of Th1 cells, but no significant clinical differences were observed.