pollen food allergy syndrome (PFAS)
Last edited 04/2023 and last reviewed 05/2023
Pollen-food allergy syndrome (PFAS)
- is an immunoglobulin E-mediated immediate allergic reaction caused by cross-reactivity between pollen and the antigens of foods - such as fruits, vegetables, or nuts - in patients with pollen allergy
- is a common adverse reaction occurring few minutes after the consumption of vegetable foods in patients with pollen-induced seasonal allergic rhinoconjunctivitis (SAR) (2)
- in Northern European countries
- many patients with birch tree pollen sensitization develop PFAS that is induced by plant food, such as tree nuts and fruits, particularly those of the Rosaceae family
- in Southern European countries
- PFAS is mainly represented in patients polysensitized to various pollens
- in Japan
- sensitization to Japanese cedar is the main trigger of airborne allergy, and it's associated with PFAS due to fresh tomato in some cases
- in Australian children
- watermelon is the most common triggering food among children with grass pollen and birch allergy
- watermelon is the most common triggering food among children with grass pollen and birch allergy
- in Northern European countries
- pathogenesis of PFAS
- is linked to a respiratory allergy to pollens and subsequent cross-reactivity between pollens and homologous epitopes contained in plant-derived food proteins (class 2 food allergy) (2)
- is a type I cross-reaction mediated by IgE antibodies between an aeroallergen and a plant-derived antigen (3)
- is a type I cross-reaction mediated by IgE antibodies between an aeroallergen and a plant-derived antigen (3)
- is linked to a respiratory allergy to pollens and subsequent cross-reactivity between pollens and homologous epitopes contained in plant-derived food proteins (class 2 food allergy) (2)
- is often called oral allergy syndrome because symptoms appear mainly in the lips, mouth, and pharynx
- clinically characterized most frequently by isolated oral and pharyngeal symptoms at immediate onset following food intake, which is called oral allergy syndrome (OAS) (2)
- symptoms typically consist of localized oral symptoms such as numbness of the lip or mouth, itching, tingling and swelling of lips, tongue, palate and pharynx without systemic symptoms (3)
- PFAS however is a more appropriate term because the symptoms appear around the mouth as well as in the gastrointestinal tract and respiratory organs (1)
- symptoms of PFAS are generally restricted to the oropharyngeal mucosa and occur immediately, or in 5-10 min after consuming fresh fruits, vegetables, nuts, legumes and seeds (2)
- oropharyngeal symptoms comprise:
- labial and oropharyngeal pruritus,
- paresthesia,
- angioedema of the oral mucosa, lips, tongue, palate and pharynx,
- itchy ears,
- mucosal red patches and blisters and sensation of laryngeal tightness that may cause hoarseness (OAS)
- symptoms typically last for a few minutes to half an hour
- systemic reactions have been reported in 2-10% of cases
- oropharyngeal symptoms comprise:
- pollen sensitization is uncommon in young children, and PFAS occurs more frequently in older children, adolescents, and adults (1)
Reference:
- Jeon YH. Pollen-food allergy syndrome in children. Clin Exp Pediatr. 2020 Dec;63(12):463-468. doi: 10.3345/cep.2019.00780. Epub 2020 May 14. PMID: 32403897; PMCID: PMC7738766.
- Mastrorilli C, Cardinale F, Giannetti A, Caffarelli C. Pollen-Food Allergy Syndrome: A not so Rare Disease in Childhood. Medicina (Kaunas). 2019 Sep 26;55(10):641. doi: 10.3390/medicina55100641. PMID: 31561411; PMCID: PMC6843262.
- Kar Kurt O et al [Pollen food allergy syndrome]. Tuberkuloz ve Toraks. 2017 Jun;65(2):138-145. DOI: 10.5578/tt.32167. PMID: 28990893.