What is the next step after a positive food allergy panel, do I refer to an allergist?

Management of Positive Food Allergy Panel Results

Yes, referral to an allergist is strongly recommended following a positive food allergy panel to confirm the diagnosis and establish appropriate management. 1

Why Referral to an Allergist is Necessary

• A positive food allergy panel alone has poor positive predictive value and does not necessarily indicate a true food allergy, as having allergen-specific IgE is not always indicative of clinical disease 1
• Allergy testing cannot predict future risk, and IgE testing has poor positive predictive value despite being sensitive in detecting allergen-specific IgE 1
• Allergists can perform additional diagnostic testing, including oral food challenges when necessary, to verify the clinical relevance of positive test results 1
• Food allergies can potentially cause severe reactions including anaphylaxis, which can be life-threatening, making proper diagnosis and management critical 2

Immediate Management Steps Before Allergist Consultation

• Prescribe an epinephrine autoinjector and provide training on its use, especially if the patient has had any symptoms suggestive of food allergy 1
• Instruct the patient to temporarily avoid the food items that tested positive until further evaluation by an allergist 1
• Provide education on recognizing the signs and symptoms of allergic reactions 1
• Schedule follow-up within 1-2 weeks to ensure appropriate referral and interim management 1

What to Expect from the Allergist Consultation

The allergist will:

• Perform a detailed clinical history to correlate positive test results with actual symptoms 1
• Consider additional diagnostic testing which may include:
  • Skin prick testing 3
  • Specific IgE blood testing 4
  • Oral food challenges in controlled settings when necessary 1
• Formulate an emergency anaphylaxis action plan 1
• Provide education on food avoidance strategies and label reading 1

Important Considerations and Pitfalls

• Do not overinterpret positive food allergy panel results - many patients with positive tests can tolerate the foods without symptoms 1
• Patients should not discontinue oral antihistamines before blood IgE testing, but should discontinue them before skin testing (3-10 days depending on the specific medication) 4
• Not all food-allergic patients are "highly allergic" - severity and threshold of reactivity vary significantly between individuals 5
• The nine foods that account for more than 90% of IgE-mediated food allergies in the US are crustacean shellfish, dairy, peanut, tree nuts, fin fish, egg, wheat, soy, and sesame 2
• Peanut is the leading food-related cause of fatal and near-fatal anaphylaxis in the US, followed by tree nuts and shellfish 2

Follow-up Recommendations

• Patients with confirmed food allergies should have yearly follow-up for retesting, as some food allergies can resolve over time 1
• For children with food allergies, provide documentation for school (food allergy emergency action plan) 1
• Ensure the patient understands the importance of carrying emergency medications and checking expiration dates regularly 1

Remember that food allergy management requires a careful balance between safety and quality of life, with the goal of preventing serious reactions while minimizing unnecessary dietary restrictions 5.