Systemic Reactions in Pediatric Patients Receiving Standardized Allergen Subcutaneous Immunotherapy with and without Seasonal Dose Adjustment

BACKGROUND: The 2003 Joint Task Force on Practice Parameters recommended standardizing allergen subcutaneous immunotherapy (SCIT). Data from longitudinal surveillance survey in North America reported a systemic reaction (SR) rate of 0.1% to 0.2% of injection visits. The rate of SR to standardized SCIT in pediatric patients has not been well evaluated. OBJECTIVE: The objective of this study was to evaluate the rate of SRs to standardized SCIT in pediatric patients aged 5 to 18 years in a single tertiary care center in the United States. METHODS: A retrospective chart review was conducted in 2 groups: group 1 started SCIT within a period extending from January 2009 to June 2012, whereas group 2 started SCIT within a period extending from January 2013 to June 2016. The protocol was modified in group 2 such that updosing and maintenance doses were adjusted in the spring for tree and grass pollen and in the fall for weed pollen. RESULTS: There were a total of 128 patients in group 1 and 118 patients in group 2. The rate of SR was 0.429% in group 1 and 0.364% in group 2, which was not significant. There was no difference in the severity of SR in the 2 groups with no-fatal or near-fatal SR noted. Asthma was a significant risk factor in the younger age subgroup aged 5 to 11 years. CONCLUSIONS: Standardized SCIT appears to be associated with an SR rate of 0.429% to 0.364% of visits in pediatric patients. Protocol modification did not lead to a significant drop in SR. Larger multicenter studies are required to further evaluate the rate of SRs from standardized SCIT. (C) 2017 American Academy of Allergy, Asthma & Immunology