What is the clinical and immunological efficacy and safety of local nasal immunotherapy (LNIT) for patients with allergic rhinitis (AR)?
BOTTOM LINE
LNIT is a safe alternative immunotherapy route that improves clinical symptoms, reduces medication usage, and increases the nasal provocation threshold.
BACKGROUND: Allergen immunotherapy (AIT) is the only available curative treatment for AR. LNIT, the induction of immunotolerance in the nasal cavity, is less invasive and time-consuming than commonly used subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT).
STUDY DESIGN: Systematic review and meta-analysis.
SETTING: Faculty of Medicine Siriraj Hospital, Division of Rhinology and Allergy, Department of Otorhinolaryngology, Mahidol University, Bangkok, Thailand.
SYNOPSIS: Researchers employed the Ovid, MEDLINE, and Embase databases to search for randomized controlled trials comparing LNIT and placebo. Study criteria were inclusive of any adult or pediatric patients who met diagnostic criteria for AR, and any allergen, type of preparation, delivery, dosage, or duration. The 20 included studies had a combined total of 698 participants. Outcomes were total nasal symptom score (TNSS), symptom–medication score (SMS), medication score, immunological assessment, and nasal provocation threshold. Results showed the LNIT group had greater post-treatment improvement in TNSS, SMS, and medication score. Itching had the highest degree of improvement, followed by sneezing, rhinorrhea, and nasal obstruction. Immunological assessments showed no significant differences in serum-specific IgE or nasal eosinophil cationic protein. Only serum IgG significantly increased with LNIT, and the post-treatment nasal provocation threshold was higher with LNIT. No significant adverse events were reported.
CITATION: Kasemsuk N, Ngaotepprutaram P, Kanjanawasee D, et al. Local nasal immunotherapy for allergic rhinitis: a systematic review and meta-analysis. Int Forum Allergy Rhinol. 2022;12:1503–1516.