Systemic Allergic Reactions and Anaphylaxis Associated with Allergen Immunotherapy

Area of Science:

• Allergy and Immunology
• Immunotherapy Research
• Clinical Risk Management

Background:

• Subcutaneous allergen immunotherapy (SCIT) is an established treatment for allergic rhinitis, asthma, atopic dermatitis, and preventing Hymenoptera venom anaphylaxis.
• While beneficial, SCIT carries the risk of systemic allergic reactions (SRs), necessitating careful patient evaluation.
• Understanding these risks is crucial for optimizing SCIT's risk-benefit profile.

Purpose of the Study:

• To review the incidence and contributing factors of systemic allergic reactions (SRs) and fatal reactions (FRs) associated with SCIT.
• To propose risk management strategies aimed at preventing and reducing SCIT-related adverse events.
• To provide an updated perspective on the safety of SCIT in clinical practice.

Main Methods:

• Literature review of studies on subcutaneous allergen immunotherapy (SCIT) and associated adverse events.
• Analysis of estimated incidence rates for systemic reactions (SRs) and fatal reactions (FRs) from 2008-2018.
• Synthesis of factors contributing to SCIT-related anaphylaxis and fatal outcomes.

Main Results:

• Systemic allergic reactions (SRs) occur at a rate of approximately 0.1% (1 per 1000 injection visits).
• Life-threatening anaphylactic events are rare, estimated at 1 in 160,000 injection visits.
• Factors contributing to SRs and fatal reactions are identified and discussed.

Conclusions:

• SCIT is a valuable treatment, but potential risks like systemic reactions and anaphylaxis must be managed.
• Implementing proposed risk management strategies can enhance SCIT safety.
• Further research and vigilance are needed to minimize SCIT-associated adverse events.