Objective To investigate the effects of montelukast sodium combined with mometasone furoate nasal spray on immune regulation and symptom improvement of children with adenoid hypertrophy.

Methods A total of 107 children with adenoid hypertrophy treated in the Department of Otolaryngology, Hebei Children's Hospital/Hebei Provincial Clinical Research Center for Child Health and Disease from June 2022 to March 2024 were selected as the study subjects. According to a computer-generated random number sequence, block randomization and an opaque sealed envelope method were used to divide them into combination group (n=53) and monotherapy group (n=54). The monotherapy group was treated with mometasone furoate nasal spray, while the combination group was treated with montelukast sodium combined with mometasone furoate nasal spray. The treatment was lasted for 8 weeks, and outpatient follow-up was conducted for 12 months. The clinical efficacy, scores of nasal symptoms, adenoid thickness to nasopharyngeal width ratio (A/N), immune indicators, inflammatory response, adverse reactions, and recurrence rate during the follow-up period were compared between the two groups.

Results After 8 weeks of treatment, the total effective rate in the combination group was 98.11%, which was significantly higher than 85.19% in the monotherapy group (P < 0.05). After 8 weeks of treatment, the scores of nasal-related symptoms and A/N in both groups decreased significantly, and the scores of nasal-related symptoms and A/N in the combination group were significantly lower than those in the monotherapy group (P < 0.05). After 8 weeks of treatment, the level of transforming growth factor-β1 (TGF-β1) and the ratio of helper T cell 17 to regulatory T cell (Th17/Treg) decreased significantly in both groups, and the level of TGF-β1 and Th17/Treg in the combination group were significantly lower than those in the monotherapy group (P < 0.05). After 8 weeks of treatment, the levels of interleukin (IL)-4, IL-5, IL-7, and leukotriene B4 (LTB4) decreased significantly in both groups, and the levels of IL-4, IL-5, IL-7, and LTB4 in the combination group were significantly lower than those in the monotherapy group (P < 0.05). The incidence rate of adverse reactions in the combination group and the monotherapy group was 9.43% (5/53) and 5.56% (3/54) respectively, and the recurrence rates during the follow-up period were 3.77% (2/53) and 7.41% (4/54) respectively, and there were no significant differences between groups (P>0.05).

Conclusion The combination therapy of montelukast sodium and mometasone furoate nasal spray can effectively improve nasal symptoms such as nasal itching and nasal congestion, reduce adenoid volume, regulate immune balance, and alleviate inflammatory response in children with adenoid hypertrophy.