Your child may be allergic to fruit because of Pollen Food Syndrome (PFS), a type of cross-reactivity allergy. This occurs when your child's immune system mistakes proteins in certain raw fruits, vegetables, and nuts for pollen, triggering an allergic reaction.
Understanding Pollen Food Syndrome
Here's a breakdown of why this happens:
- Cross-Reactivity: The proteins in some raw fruits and vegetables are structurally similar to proteins found in plant pollens (like birch, ragweed, or grass pollen).
- Immune System Confusion: Your child's immune system, which is already sensitized to pollen, recognizes these similar proteins in the fruit and reacts as if it were encountering pollen.
- Allergic Reaction: This mistaken identity leads to an allergic reaction, usually mild, that primarily affects the mouth, lips, and throat.
Risk Factors
While the exact reason why some children develop PFS isn't fully understood, certain factors increase the risk:
- Hay fever (allergic rhinitis): Children with seasonal allergies to pollen are more susceptible.
- Asthma: Having asthma can also increase the likelihood.
- Eczema (atopic dermatitis): A history of eczema is another potential risk factor.
- Family History: A family history of allergies can increase the risk of a child developing any allergy, including fruit allergies through PFS.
Symptoms of Pollen Food Syndrome
The symptoms of PFS are usually mild and localized to the mouth area. They may include:
- Itching or tingling of the mouth, lips, tongue, or throat.
- Mild swelling of the lips or tongue.
- Scratchy throat.
In rare cases, more severe reactions can occur, although this is uncommon.
What Fruits Are Commonly Involved?
The specific fruits that trigger PFS depend on the type of pollen your child is allergic to. Here are some common associations:
- Birch pollen: Apples, pears, peaches, plums, cherries, carrots, celery, almonds, hazelnuts.
- Ragweed pollen: Bananas, melons (cantaloupe, watermelon), zucchini.
- Grass pollen: Melons, tomatoes, oranges.
Important Considerations:
- Cooking the fruit often eliminates the problem: Heat breaks down the proteins that cause the allergic reaction. Cooked fruits and vegetables are generally well-tolerated.
- Reactions are usually mild: While uncomfortable, PFS reactions are rarely life-threatening.
- Diagnosis by an allergist is important: An allergist can perform allergy testing to determine the specific pollen and food allergens involved.
- Management: Your allergist can provide guidance on managing PFS, which may include avoiding certain raw fruits, carrying an antihistamine for mild reactions, and having an epinephrine auto-injector (EpiPen) for severe reactions (though these are rarely needed for PFS).
