[Oral allergy syndrome (OAS)]

Area of Science:

• Immunology
• Allergology
• Clinical Medicine

Context:

• Pollen-food allergy syndrome (PFAS), also known as oral allergy syndrome (OAS), affects individuals sensitized to pollen.
• It is characterized by local oral and throat reactions upon ingestion of specific raw plant foods.
• The birch-apple pairing is a classic example, with apples, pears, and plums frequently implicated.

Purpose:

• To describe the clinical presentation, triggers, diagnosis, and management of pollen-food allergy syndrome.
• To highlight the role of pollen-specific allergens in triggering cross-reactive food reactions.
• To inform healthcare professionals and patients about this common allergic condition.

Summary:

• PFAS involves IgE-mediated cross-reactivity between pollen allergens (e.g., PR-10, profilin, lipid transfer proteins) and homologous proteins in certain raw foods.
• Symptoms range from mild oral itching to severe systemic reactions like anaphylaxis.
• Diagnosis relies on patient history, skin prick tests, and specific IgE testing, with oral food challenges for confirmation.
• Prevalence varies geographically, impacting 30-60% of food allergy cases, with avoidance of causative foods as the primary intervention.

Impact:

• Increased awareness of PFAS can lead to earlier diagnosis and appropriate management, reducing patient morbidity.
• Understanding cross-reactivity aids in personalized dietary recommendations and allergen avoidance strategies.
• This knowledge supports public health initiatives aimed at managing allergic diseases effectively.