Systemic Reactions to Subcutaneous Immunotherapy (SCIT): A Retrospective Study
Sunday, March 4, 2018: 2:15 PM
S310AB (Convention Center)
Sonam Sani, MD, , , ,
RATIONALE: Subcutaneous allergen immunotherapy (SCIT) is efficacious in patients with allergic rhinitis, asthma and atopic dermatitis. However, SCIT can be associated with systemic reactions (SR). Our aim was to identify risk factors for SR to SCIT in our population.

METHODS: We conducted an IRB-approved, 10-year, retrospective chart review of 459 patients who received SCIT in our clinic. Data gathered for statistical analysis included patient demographics, atopic history, treatment allergens and rate of SR. Patients were cohorted according to age: 90 pediatric patients (5-18y), 335 adults (19-64y) and 34 seniors (>65y).

RESULTS: A SR (n=177) was identified in 24.8% of patients (n=114). Reactions were classified as Class 1 (n=152), Class 2 (n=21), Class 3 (n=2) and Class 4 (n=2) according to the WAO SR grading system. There were no observed differences in the number of SR with respect to age group. Females were more likely to have a SR (p=0.02) overall, as well as more than one reaction (p=0.002). Other risk factors included: history of food allergy (p=0.05), drug allergy (p=0.005) or positive skin test to cat and/or dog (p=0.01). Additionally, patients receiving IT to cat and/or dog (p=0.004) or dust mite (p=0.03) were more likely to have a SR.

CONCLUSIONS: In our patient population, the majority of SR to SCIT occurred in females, patients with drug or food allergies, and those receiving pet or dust mite IT. Larger studies are warranted to further assess if these patient subsets are at higher risk for SR and would require more cautious administration of SCIT.