Overview: Why oral food challenges (OFCs) matter for children
Oral food challenges are a critical tool in pediatric allergy care. They help determine whether a child has outgrown a food allergy or still reacts to a specific antigen. While generally safe when conducted in a controlled hospital setting, OFCs carry a small risk of allergic reactions, including rare but potentially severe events. Recent research published in Nutrients adds important nuance to which children are most at risk of reacting during OFCs and how clinicians can navigate these risks more effectively.
What the study looked at
The single-center retrospective study analyzed 205 OFCs performed on pediatric patients at a dedicated Allergy Department from 2014 onward. The focus was on foods commonly tested in OFCs, with cow’s milk protein and hen’s egg accounting for roughly half of all challenges. Researchers examined preexisting allergic comorbidities, sociodemographic data, and test outcomes, using a range of statistical methods to identify risk factors for OFC failure.
Key findings: two main risk factors
The study found an overall OFC failure rate of 32.2%. Most reactions were mild to moderate, presenting as mucocutaneous symptoms such as hives or itching. Severe, multisystemic reactions were rare but did occur in a minority (2.0%), with all requiring epinephrine. The analysis identified two significant predictors of OFC failure:
- Asthma diagnosis: Children with asthma were more likely to react during OFCs (p = 0.028).
- Multi-food allergy: Children with multiple food allergies showed higher odds of a positive challenge (p = 0.021).
Moreover, the combination of asthma with a history of anaphylaxis, or multi-food allergy with prior anaphylaxis, further amplified the risk of a failed OFC. These findings underscore the importance of careful patient selection and risk stratification before scheduling an OFC, especially for those with respiratory or multiple-food allergy comorbidities.
How can screening improve safety?
The researchers highlighted the potential of integrating clinical history with objective biomarkers to guide decision-making around OFCs. In particular, they explored how specific IgE (sIgE) thresholds could inform safety planning. For example, they identified a baked milk sIgE level (58.1 kU/L) as a useful cutoff to balance sensitivity and specificity in predicting reactions during OFCs. Importantly, these thresholds should be used as adjuncts to clinical judgment, not as definitive predictors of long-term tolerance.
In practice, such an approach can help clinicians:
- Identify higher-risk patients who may require enhanced monitoring, slower dose escalation, or alternative testing strategies.
- Tailor pre-testing assessments to include asthma control status and the breadth of food allergies.
- Communicate risks clearly with families to support informed decision-making and reduce anxiety around OFCs.
Practical implications for clinicians and families
While OFCs remain a cornerstone of allergy diagnostics, this study reinforces that safety hinges on meticulous screening and supervision. For children with asthma or multiple food allergies, clinicians should consider more conservative testing plans, additional pre-test evaluations (including up-to-date asthma management), and readiness to treat reactions promptly. Parents and caregivers should be reassured that, when conducted in a properly equipped setting, OFCs are generally safe, with most reactions being mild and manageable.
Conclusion: A path toward safer, personalized OFCs
The study contributes valuable insights into which pediatric patients are at higher risk for OFC reactions and how to mitigate that risk through integrated clinical assessment and data-driven thresholds. By combining detailed clinical histories with judicious use of sIgE data and careful monitoring, clinicians can continue to rely on OFCs as a safe, essential diagnostic tool that supports accurate food allergy management for children.
