PFS Is Increasingly Prevalent
PFS - Pollen food allergy syndrome also called oral allergy syndrome — is common and increasingly prevalent. PFS can begin at any age but usually starts in pollen-sensitized school-age children and adults with seasonal allergic rhinitis.
The British Society of Allergy and Clinical Immunology (BSACI) put out a new practitioner guideline on this. It focuses on birch tree pollen, the major sensitizing PFS allergen in Northern Europe. Providers may be able to diagnose PFS related to birch pollen from clinical history alone, including the foods involved and the rapidity of symptom onset.
This guideline helps primary care doctors differentiate pollen food syndrome (PFS) - a cross-reactive allergic reaction to certain raw, but not cooked, plant foods - from other food allergies.
Symptoms From Similar Proteins in Food
Mild to moderate allergic symptoms develop quickly when people sensitized to birch pollen eat raw plant foods that contain proteins similar to those in the pollen, such as pathogenesis-related protein PR-10. The allergens are broken down by cooking or processing.
Symptoms usually occur immediately or within 15 minutes of eating. (Although, keep in mind that many and most of “food reactivities” are NOT immediate and can occur days or weeks after consuming the “offending” food.
Symptoms
Symptoms usually occur immediately or within 15 minutes of eating. So these are immediate types of allergic reactions, again, NOT like most food sensitivities.
Patients may have tingling; itching or soreness in the mouth, throat, or ears; mild lip and oral mucosa angioedema; itchy hands, sneezing, or eye symptoms; tongue or pharynx angioedema; perioral rash; cough; abdominal pain; nausea; and worsening of eczema. In children, itch and rash may predominate.
Triggers
PFS triggers vary depending on a person's pollen sensitization, which is affected by their geographic area and local dietary habits. In the United Kingdom, almost 70% of birch-allergic adults and more than 40% of birch-allergic children have PFS. That is where these guidelines came from, the UK.
Typical triggers include eating apples, stone fruits, kiwis, carrots, celery, hazelnuts, almonds, walnuts, soymilk, and peanuts, as well as peeling potatoes or other root vegetables.
Freshly prepared vegetable or fruit smoothies or juices, celery, soymilk, raw nuts, large quantities of roasted nuts, and concentrated nut products can cause more severe reactions. But remember, these reactions are not extremely common.
Diagnostic Clinical History
If a patient answers yes to these questions, they almost certainly have PFS, the author investigators write:
Are symptoms caused by raw fruits, nuts, carrots, or celery?
Are the same trigger foods tolerated when they're cooked well or roasted?
Do symptoms come immediately or within a few minutes of eating?
Do symptoms occur in the oropharynx and include tingling, itching, or swelling?
Does the patient have seasonal allergic rhinitis or sensitization to pollen?
Testing
This is a case where skin testing, which tests for the immunoglobulin IgE, is effective. For many “delayed food reactivities (and not true allergies)” blood labs work better.
An oral food challenge to confirm PFS is needed only if the history and diagnostic tests are inconclusive or if the patient is avoiding multiple foods.
Dietary Management
PFS is managed by excluding known trigger foods. Duh.
But, remember, if you sleuth and fix the “root cause”, often many reactivities improve or go away. However allopathic approaches are not set up to look at these issues through these lenses.
Dr Jill A. Poole chimes in:
"People are not allergic to the specific food, but they are allergic to a seasonal allergen, such as birch tree, that cross-reacts with the food protein, which is typically changed with cooking," she explained in an email.
"This differs from reactions by those who have moderate to severe allergic food-specific reactions that may include systemic reactions like anaphylaxis from eating certain foods," she said.
"Importantly, the number of cross-reacting foods with seasonal pollens continues to grow, and the extent of testing has expanded in recent years.
Many times, in my experience, cleaning up someone’s gut, improving their digestive abilities, avoiding food reactions for a while, balancing hormones, and reducing inflammation, helps get RID of these sensitivities.
In my opinion, we are walking around with more sensitivities as we have more imbalances and toxic exposures. When these are addressed, often we, the host, become stronger. Less reactive.
So don’t buy into permanent diagnoses or permanent avoidances. There is hope. But it takes you getting more Vitamin R = resilience in your tissues, to then have fewer allergic issues.
Knowledge is power.
Dr. B.
References:
Clinical & Experimental Allergy. Published online August 17, 2022. Full text
For more news, follow Medscape on Facebook, Twitter, Instagram, and YouTube
Credits:
Lead image: Irina Kardasheva/Dreamstime
Image 1: University of Pittsburgh School of Medicine
Image 2: Nebraska Medicine
Medscape Medical News © 2022 WebMD, LLC
Send news tips to news@medscape.net.
Cite this: When Is an Allergic Reaction to Raw Plant Food Due to Tree Pollen? - Medscape - Sep 21, 2022.