Subcutaneous Immunotherapy Safe, Effective in Pediatric Allergic Rhinitis/Asthma

Subcutaneous immunotherapy (SCIT) for children with allergic rhinitis and/or asthma safely and effectively improves nasal symptoms and asthma after 1 year of treatment, according to study findings published in International Journal of Pediatric Otorhinolaryngology.

Subcutaneous immunotherapy sometimes needs to be curtailed due to adverse reactions (ARs) in patients. Investigators aimed to quantify the incidence of ARs during subcutaneous allergen-specific immunotherapy (AIT) and to identify risk factors associated with such ARs.

The researchers conducted a retrospective study of 344 patients with allergic rhinitis and/or asthma who underwent SCIT between 2005 and 2021 and were less than 18 years of age. The investigators used descriptive and univariate/multivariate logistic regression analyses to recognize adverse event risk factors. Among all patients (mean age 133.1±41.0 months, 42.2% >12 years old; 33.4% girls) 40.1% were mono-sensitized. There were 13.7% who had asthma, 60.2% allergic rhinitis, and 26.2% asthma and allergic rhinitis.

Multiple allergen content was administered to 45.6% of the patients (121 pollen mix, 36 other [mite/alternaria]) and single allergen content to 54.4% of the patients (62 mite, 114 grass mix, 11 olea). In total, more than 33,000 injections were administered, resulting in 840 ARs recorded in 195 patients. Among those ARs, 31.1% occurred during the up-dosing phase, and 68.8% occurred at the maintenance phase.

Among the ARs that occurred, 75.2% were local, 19.0% large local, and 5.7% were systemic. Systemic reactions (28 Grade 1; 12 Grade 2; 8 Grade 3) occurred in 31 patients (39 occurrences at maintenance, 9 at up-dosing).  Adrenaline was administered to all patients with a Grade 3 systemic reaction.

Adverse reactions, especially those that were local, most commonly occurred in patients less than 12 years of age (P <.001). A greater incidence of adverse reactions were seen in patients sensitized with mite and grass pollen, those who received SCIT with pollen mixture, and those who received SCIT containing calcium-phosphate as adjuvant.

The researchers noted that in univariate analyses, local reactions were risk factors for large local reactions (odds ratio (OR)=3.591; 95% CI, 2.064-6.247; P <.001) and systemic reactions (OR=2.190; 95% CI, 1.005-4.722; P =.046). Visual Analog Scale and asthma symptom control test scores and total nasal symptom scores decreased after treatment for 1 year (P <.01).

Study limitations include the retrospective design, insufficient/missing data, and the single-center design.

Overall, SCIT is “a safe treatment method especially in children under 12 years of age” and “an effective treatment method in children with allergic rhinitis and/or asthma,” study authors concluded. Because of these findings, “patients with pediatric allergic rhinitis and asthma “should be evaluated for early initiation of SCIT as soon as possible,” the investigators added.

Reference

Duman Senol H, Topyildiz E, Ekici B, Gulen F, Demir E. Effectiveness and adverse reactions to subcutaneous immunotherapy in children with allergic rhinitis/asthma. Int J Pediatr Otorhinolaryngol. Published online August 19, 2022. doi:10.1016/j.ijporl.2022.111292